BULLETIN OF THE FLORIDA STATE MUSEUM BIOLOGICAL SCIENCES Volume 11 Number 4 THE LAND AND FRESHWATER SNAILS OF CAMPECHE Fred G. Thompson UNIVERSITY OF FLORIDA Gainesville 1967 Numbers of the BULLETIN OF THE FLORIDA STATE MUSEUM are pub- lished at irregular intervals. Volumes contain about 800 pages and are not nec- essarily conipleted in any one calendar year. WALTER AuFFENBERG, Managing Editor OLIVER L. AUSTIN, JR., Editor Consultants for this issue: HORACE B. BAKER HENRY VAN DER SCHALIE Communications concerning purchase or exchange of the publication and all manuscripts should be addressed to the Managing Editor of the Bulletin, Florida State Museum, Seagle Building, Gainesville, Florida. 82601 Published June 20, 1967 Price for this issue $.65 THE LAND AND FRESHWATER SNAILS OF CAMPECHE FRED G. THOMPSON1 SYNOPSIS.-This review of the land and freshwater snails of Campeche, Mexico, records 59 species and subspecies of snails including 47 terrestrial and 12 ac4uatic forms; 21 are recorded for the first time from the state. Miradiscops haplocochlion is described as new; 11 previously recognized taxa are placed in synonymy. Streptostula, subgenus Chersomitra, is redefined and the soft anatomy of its type species S. nigricans (Pfeiffer) is described for the first time. Brach!/Podella dubia (Pilsbry) is resurrected as a species and distinguished from B. speluncae (Pfeiffer). New descriptions are given for both these species and for Choanopoma andrewsae (Ancey) Material from adjacent states pertaining to Campeche species is also included. TABLE OF CONTENTS INTRODUCTION 222 Succineidae 232 GAZETTEER 223 Spiraxidae 232 ANNOTATED LIST 224 Ferussaciidae 240 Achatinidae 241Pomatiidae 224 Systrophiidae .-_... 241Cyclophoridae 227 Zonitidae 243 Helicinidae 228 Orthalicidae 244 Pilidae 230 Urocoptidae 249 Hydrobiidae 230 Xanthonichidae 253 Physidae 231 Polygyridae 254 Veronicellidae 231 Sagdidae 255 Pupillidae 231 LITERATURE CITED 255 1 The author is Interim Assistant Curator in Malacology, Florida State Museum. Most of his researches have dealt with the systematics and zoogeography of land and freshwater mollusks, with particular emphasis on the American tropics and Florida. Manuscript received 18 September 1966. Thompson, Fred G. 1967. The land and freshwater snails of Campeche. Bull. Florida State Mus., vol. 11, no. 4, pA 221-256. 222 BULLETIN FLORIDA STATE MUSEUM Vot. 11 INTRODUCTION This study is based primarily upon material the author collected from 24 field stations in Campeche during June 1965, and includes material he collected from adjacent states that add noteworthy dis- tribution records for Campeche species. This study also considers extra-linlital species that affect the systematics of Campeche forms. Campeche is a large state of 50,952 square kilometers in the Yu- catan Peninsula. The western third is part of the extensive Eastern Tabasco-Campeche Aliuvial Plain; the remainder is formed of low, rolling karst hills. The state is nearly uniform in its physiography, and elevations vary from sea level to about 850 meters. The Only promi- nent topographic feature is a short spur of the Sierrita de Tikul, which rises about 100 meters above the surrounding countryside in the northern corner of the state (West, 1964: 70-73). The karst de- velopment allows few permanent bodies of water except in the western alluvial region. Those that do exist are generally inaccessible. A climatic transition from northwest to southeast is reflected in the gradual change from the xeric vegetation along the coast to quasi- rain forest (Wagner, 1964: 228). For purposes of this study the wet forests are simply referred to as rain forest. Terrestrial mollusks have been collected primarily from the karst regions of the state. Very little material is known from the wetter alluvial plains, except for a collection Morelet made at Palizada in 1852. Therefore most papers pertaining to Campeche ( including this one) are ecologically biased in their coverage. No comprehensive report has been made previously on the land and freshwater snails of Campeche.' All early records for the state appeared as miscellaneous inclusions ,in various monographs and faunal reviews. Bequaert and Clench (1938, 1986) summarized what little was known then and reported a few additions. More recently Branson and McCoy (1968, 1965) reported on small amounts of ma- terial collected incidental to other studies. Considering the fragmen- tary and varied nature of previous contributions, a surprisingly large number of species have been reported. Currently 59 species and subspecies of land and freshwater snails are known from Campeche. Previous workers have reported 47 forms from the state; 5 of these are of doubtful occurrence in Campeche and 4 are synonyms of other forms. Material that I collected includes 40 species kind subspecies, 21 of which are new records for the state. 1967 THOMPSON: SNAILS OF CAMPECHE 223 The following land snails recorded from Campeche are considered of doubtful occurrence: Neocyclotus dysont aureus (Bartsch and Morrison) Catinetla atara (Say) f Euglan(lina ghiesbreghti (Pfeiffer) Euglandina sowerbyana (Pfeiffer) Polygyra oppilata (Morelet) The following four named fofms recorded from Campeche are now considered synonyms: Streptostyla maslini Branson and McCoy (- S. meridana) Streptostyla toltecorum Branson and McCoy (- S. meridana) Bulimulus inermis (Morelet) ( - B. unicolor) Bulimulus igna©us (Reeve) ( - B. unicolor) Most of the material comprising this study is deposited in the Florida State Museum at the University of Florida. Representative specimens are also deposited in the Museo Nacional de Mexico. This material was supplemented by speciniens borrowed from other museums. Collecting localities are listed from .west to east and from south to north. Records from earlier published reports included in the species accounts appear in parentheses. For many helpful suggestions and other courtesies that have aided in the completion of this study I am indebted to the following people: Henry van der Schalie and John B. Burch, University of Michigan, Museum of Zooldgy (UMMZ); Joseph P. E. Morrison, Harold A. Rehder and Joseph Rosewater, United States National Museum ( USNM); Tucker Abbott, Academy of Natural Sciences of Philadel- phia ( ANSP); Wayne King, Florida State Museum, University of Florida (UF). The shell drawings were made by Barbara Weinstein, Miami, Florida. Field material was collected with the aid of The National Institutes of Health research grant NIGMS - RGB, GM 12800. GAZETTEER The following place names in Campeche and Quintana Roo are cited in the text. Yucatecan place names are on most maps and are not included. CAMPECHE Campeche.-(19° 50' N, 90° 81' W). CayM.-A small village about 27 miles e.s.e. Campeche (19° 45' N, 90° 10' W). 224 BULLETIN FLORIDA STATE MUSEUM Vol. 11 Champot6n.-(19° 21' N, 90° 48' W). Ciudad de Carmen.-(18° 88' N, 91° 50' W). Dzibalchdn.-(19° 81' N, 89° 45' W). Edznd.-Mayan ruins about 11 miles s.s.w. of Cayal (19° 85' N, 90° 15' W). Escarcega.-(18° 86' N, 90° 44' W). H6pelch6n.-(19° 16' N, 89° 52' W). Ich-Ek.-A small village about 10 diles w.s.w. of Hopelchin. (19° 44' N, 89° 58' W). Palizada.-(18° 15' N, 92° 06' W). Pixtun.-A small village 18 miles south of Champot6n (19° 06' N, 90° 48' W). San Geronimo.-( 18° 35' N, 92° 40' W). Seybaplaya»(19° 88' N, 90° 39' W). Silvituc.-(18° 42' N, 90° 16' W). Tenabo.-(20° 08' N, 90° 12' W). Tikinmul.-A small village about 23 miles e.s.e. Campeche (19° 46' N, 90° 18' W). Xpujil.-A small village about 4 miles west of the Quintana Roo border on road from Eschrcega to Chetumdl, Quintana Roo (18° 29' N, 89° 24' W). QUINTANA Roo Xiatil.-A small village on the road from Peto, Yucatan to Felipe Carrillo Puerto, Quintana Roo (19° 40' N, 88° 26' W). ANNOTATED LIST POMATIIDAE Choanopoma largillierti (Pfeiffer) CAMPECHE: 10.2 mi. e. Escarcega; 7.2 mi. s. Pixtdn; 2.2 mi. s. Pixtdn; 0.9 mi. s.w. Champot6n; 6.1 mi. s.w. Seybaplaya; 6.2 mi. n.e. Seybaplaya; 7.1 mi. s.w. Campeche; 5.7 mi. e. Campeche; (Champot6n, Branson and McCoy, 1965: 13); ( Campeche, Solem, 1961: 200); ( 5-11 mi. e. Campeche; 32 mi. e. Campeche, Branson and McCoy, ]968: 104); 8.4 mi. w. Ich-Ek; Edzna; 5.1 mi. n.n.w. Dzibalchin, 6.0 mi. n. Dzibalch6n; 4.8 mi. n. Tenabo; 16.8 mi. s. Tenabo; 8.4 mi. s. Cayal; 8.6 mi. s. Hopelch6n; 5.1 mi. w. Tikinmdl. This is the land snail most commonly encountered in Campeche, abundent in xeric and mesic forests .and in agrarian habitats as well. 1967 THOMPSON: SNAILS OF CAMPECHE 225 The material varies greatly in sculpture and size, and both characters vary independently. This variation is ge6graphical and not ecological. I agree with Solem (1961: 201) and Branson and McCoy (1963: 104) that C. grateloupi (Pfeiffer) is not distinct from C. largillierti. Choanopoma gaigei Bequaert and Clench CAMPECHE: 19.2 mi. e. Silvituc; (Champot6n; 29.7 mi. s. Campeche, Branson and McCoy, 1965: 18), (541 mi. e. Campeche, Branson. and McCoy, 1968: 104); 5.7 mi. e. Campeche; 8,4 mi. e, Caydl; 5.1 mi. n.n.w. Dzibalchdn; 6.0 mi. n. Dzibalchon; 8.6 mi. s. Hopelch6n; 5.1 mi. w. Tikinmul. GUATEMALA (DEPT. PETEN): 1 mi. n.w. Pasco Caballo (UMMZ 64768); 4 mi. n. Paso Caballa ( UMMZ 64769). After exalnining' the material, I consider Solem's (1961: 197) criticism of these records (Goodrich and van der Schalie, 1937: 32) unwarranted. This species is found in mesic and submesic forested areas, and apparently is less tolerant of the drier conditions unddr -which C. largillierti thrives. C. gaigei also shows less t61erance to agrarian diA- turbances than does C. largillierti. I found it only in forests that had not been recently disturbed. Choanopoma andrewsae (Ancey) (Bg. 6, A-B) Cyclostoma andrewsae Ancey, 1886; Ann. Malac., 2: 251-252. Choanopoma andreu>sae (Ancey), Martens, 1890; Biol. Cent. Amer., Mbll.:16; pl 1, fig. 4. - Solem, 1961; Arch. Moll., 90:199; pl. 10, fig. 9, pl. 12, fig. 24h. Choanopoma cozumelense Richards, 1937; Proc. Anier. Phil. Soc., 77.256, pl. 4, fig. 8.- Solem, 1961; Arch. Moll., 90: 198; pl. 10, fg. 7, pl. 12, fig. 24* Choanopoma andrewsae roatanense Richards, 1988; Proc. Amer. Phil. Soc., 79: 174; pl. 3, Egs. 1 72 - Solem, 1961; Arch. Moll.,90:ZOO; pl. 10, fig. 10; pl. 12, Eg. 24i HONDURAS: Utilla Island.(Univ. Miami, ex Simpson). CAMPECHE: 5.1 mi. n.n.w. Dziblachin, 3,6 mi, s. Hopelchdn; 3.4 mi. s. Caydl. QUINTANA Roo: 4.0 mi, e, Xpujil, Campeche; 7.1 mi. n.n.w. Xiatil; 2.8 mi. s.s.e. Xiatil; San Sabastian, Cozumel Island. YUCATAN: 0.8 mi. n.e. Becanchdn; 10.0 mi. n.e. Becanchdn, Chithen Itza (6 paratyp6s of Choanopoma gaigei Bequaert and Clench, UMMZ). SHELL. Medium sized. Ovate-conical, 0.69-0.82 times as wide as long (females, 0.69-0.77; males, 0.75-0.82). Dull light brown with about 10-12 faint, broken, dark spiral bands or rows of spots which 226 BULLETIN FLORIDA STATE MUSEUM Vol. 11 may be indistinct on old shells. Outer lip and aperture same color as rest of shell. Early whorls slightly darker. Decollate, 2.8-8.5 whorls remdining (females, 8.0-8.5; males, 2.8-8.1); 2 embryonic whorls lost from decollate shells. Apical plug sloping, dorsally flattened, about 48 whorl long, purplish. Suture deeply impressed. Whorls broadly inflated, evenly rounded, not shouldered. Umbilicus transversely oblong due to lateral displacement of aperture; about 1/8-1/10 diame- ter of last whorl. Aperture adnate to preceding whorl; 0.40-0.49 times length of shell (females, 0.40-0.46; males, 0.45-0.49); broadly ovate, 1.06-1.09 times as high as wide. Inner lip projecting forward slightly. Outer lip narrow, of nearly uniform width around aperture; 0.8-0.5 mm. wide or about 1/10-1/15 width of aperture. Upper corner of outer lip vertical and slightly wider than elsewhere. Outer lip weakly reflected forward over parietal wall. Sculpture consisting of predomi- nant axial ribs and very low, broad spiral chords that are most evi- dent by the wavey appearance that they impart on the ribs, which are raised and slightly thickened over the chords. Spiral dhords most evident about periphery of whorls and in umbilical region. Axial ribs abruptly appearing on postembryonic whorls. Initially ribs are widely spaced and high, but become progressively closer and finer along spire; ribs finest and closest behind lip. About 10-12 ribs/mm. on face of last whorl in mature females, 7-8/mm. in mature males. Upper ends of ribs weakly crenulate along suture. Ribs continuous into umbilicus as sharp threads. Two embryonic whorls, when present, elevated and smooth. Operculum consisting of about 8.5 whorls. Basal chondroid plate convex. Calcareous lamella broadly reflected over face of chondroid plate, with its outer edges fused with succeeding turns to form a flat continuous calcareous plate that completely covers chondroid plate. Occasionally in specimens from Cozumel Island some turns of the lamella may fail to fuse and leave a short, narrow gap between ad- jacent whorls. Operculum not retractable into adult shell because of wide calcareous face plate. Measurements of mainland females: length, 9.2-11.3 mm.; width, 6.8-8.1 mm.; aperture height, 4.0-4.8 mm.; aperture width, 8.9-4.5 mm. Measurements of mainland males: length„ 7.6-8.1 mm.; width, 5.7-6.4 mm.; aperture height, 3.6-8.8 mm.; aperture width, 8,2-8.6 mm. Measurements for the various insular forms are given by Solem (1961). My measurements of length and width do not include the 1967 THOMPSON: SNAILS OF CAMPECHE 227 outer peristome. The distinction in. size between females and males is not so discrete as the measurements suggest. A few unsexable dead shells whose measurements are not included fall within the inter- mediate ranges. This is a widely distributed and variable species. Insular specimens tend to be smaller than those from the mainland, but differences of size and proportiohs are not constant, even within single populations. The forms from Cozumel Island (cozumelense) and the mainland tend to have distinct spiral chords below the suture, While the forms from the Bay of Honduras ( andrewsae and roatanense) usually lack subsutral chords although spiral chords are usually present in the umbilical region. The differences between the named varieties are too slight and variable to justify recognition. Solem (1961) recognizes the similarities between andrewsae and cozumelense· but contends that the forms are specifically distinct, and that the similarities are the independent result of convergent evolu- tion from different mainland species. He postulates that andrewsae evolved from C. pleurophora (Pfeiffer) and that cozumelense evolved from C. martensianum (Pilsbry). These assumptions were partially influenced by his lack of andrewsae material from the mainland. The wide -distribution and variation of andrewsae on the mainland- render untenable his theories on the evolution and relationship of these forms. C. andrewsae occurs in mesic and submesic tropical forests. It may be found with C. largillierti and C. gaigei, although the three species are ecologically segregated. C. andrewsae inhabits loose rock piles at a relatively deep level where it is constantly damp and cool. C. largillierti also occurs in rock piles as well as under scattered rocks, but usually remains beneath the surface layer of rocks where it is relatively dry. C. gaigei occurs in leaf mold and debris on the forest floor, but never under rocks even though it may be f6und within a few inches of the other two species. CYCLOPH0RIDAE Neocyclotus dusoni (Pfeiffer) CAMPECHE: 0.9 mi. S.W. Champot6n; 6.1 mi. s.w. Seybaplaya; 8.4 mi. w. Ich-Ek; 7.1 mi. s.w. Campeche; 3.4 mi. s. Caydl; 8.6 mi. s. Hopelch6n. QUINTANA Roo: 2.3 mi. s.s. e. Xiatil. 228 BULLETIN FLORIDA STATE MUSEUM VoL 11 Specimens from these localities are intermediate between N. d. berendti and N. d. cooki, and also show intergradation with N. d. ambiguum. The three subspecies are distinguished on the basis of color and sculpture. N. d. berendti is dark olivaceous brown or green with several light spiral lines, and its sculpture is Bne, irregular, and sigmoid but not vermiculated or reticulated. N. d. cooki and N. d. ambiguum have light brown unicolored shells with strong anasto- . mosing sculpture. In N. d. ambiguum the anastomosing sculpture oc- curs on the body whorl and the penultimate whorl, whereas in N. d. cooki it is confined to the body whorl. The specimens listed above are intermediate between berendti and cooki in sculpture, but only a few ~ individuals show banding. Some specimens also tend to have anasto- mosing sculpture on the penultimate whorls, indicating intergradati6n with ambiguum. Specimens from 5-11 mi. e. Campeche Branson and McCoy ( 1963: 103) recorded as N. d. aureus ( Bartsch and Morrison) of the Pacific drainage of Oaxaco probably are referable to these inter- grading forms. N. d. berendti is confined to the Yucatan Peninsula where it oc- curs in the states of Yucatan and adjacent areas of Campeche and Quintana Roo. N. d. cooki is generally distributed in the Peten region of Guatemala and adjacent parts of British Honduras, Campeche and Quintana Roo. N. d. ambiguum occurs from northern Chiapas and Tabasco north and west to central Veracruz. A series of 56 ambiguum specimens in the U.F. from near San Andres Tuxtla, Veracruz shows no integraduation with berendti as Solemn ( 1956: 53) reports. Neocyclotus d. berendti (Pfeiffer) CAMPECHE: 5.1 mi. n.n.w. Dzibalchdn; (Campeche, von Martens, 1890:5). QUINTANA Roo: 7.1 mi. n.n.w. Xiatil; 4.0 mi. e. Xpujil, Campeche. YUCATAN: 0.8 mi. n.e. Becanch6n, 10.0 mi. n.e. Becanch6n. Neocyclotus d. cooki (Bartsch and Morrison) CAMPECHE: 7.2 mi. s. Pixt6n; 19.2 mi. e. Silvituc; 10.2 mi. e. Escdrcega. HELICINIDAE Helicina t. tenuis Pfeiffer CAMPECHE: 10.2 mi. e. Escarcega. CHIAPAS: 15.8 mi. n.w. Ocozocoautla, 2700'. 1967 THOMPSON: SNAILS OF CAMPECHE 229 This species is very rare in Campeche. The only specimen col- lected was a dead shell. Helicina amoena Pfeiffer E. von Martens (1890: 28), recorded this species from Campeche from specimens collected by Albers. It has not been recorded from the state since, but may have been overlooked because of its arboreal habits. Oligyra f. #at)ida (Menke) CAMPECHE: 10.2 mi. e. Escdrcega. QUINTANA Roo: 4.0 mi. e. Xpujil, Campeche. CHIAPAS: ruins of Palenque. Its known distribution shows this species is apparently restricted to submesic forested areas. Oliggra arenicola (Morelet) CAMPECHE: 7.1 mi. s.w. Campeche; 5.7 mi. e. Campeche; 5.1 mi. w. Tikinmdl; 3.4 mi. s. CayM; 2.2 mi. s. Pixtzin; 8.4 mi. w. Ich-Ek; 8.6 mi. s. Hopelch6n; 5.1 mi. n.n.w. Dzibalchdn; 6.0 mi. n. Dzibalchdn; 7.2 mi. s. Pixhin; 19.2 mi. e. Silvituc. QUINTANA Roo: 7.1 mi. n.n.w. XiatiI; 2.8 mi. s.s.e. Xiatil. YUCATAN: 3.2 mi. s. Progreso; 1.0 mi. s.s.e. Puerto Telchac. This species is generally distributed throughout the xeric and inesic regions of the Yucatan Peninsula. Live specimens were found only on trees and shrubs. Lucidella lirata (Pfeiffer) CAMPECHE: 8.1 mi. s.w Champot6n; 5.1 mi. n.n.w. Dzibalch6n; 4.9 mi. w. Hopelchdn; 3.4 mi. s. Caydl; 7.2 mi. s. Pixtun; 10.2 mi. e. Escdrcega; 19.2 mi. e. Silvituc; (Ciudad de Carmen, Branson and McCoy, 1963:102). QUINTANA Roo: 4.0 mi. e. Xpujil; 7.1 mi. n.n.w. Xiatil. This species is characteristic of mesic and rain forests. Specimens collected from 8.1 mi. s.w. of Champot6n were found in a swampy area that remains constantly. wet. 230 BULLETIN FLORIDA STATE MUSEUM Vol. 11 PILIDAE Pomacea #agellata (Say) CAMPECHE: Laguna de Nan, 1.4 mi. w. Silvituc; temporary pond 8.8 mi. s.w. Campeche; ( 3.5 mi. s. Champot6n; 17.2 mi. s. Champot6n. Branson and McCoy, 1965:14.);(15 mi. s. Chan*ot6n; 16 km. e. ChampoMn, Bequaert and Clench, 1986: 78). Pomacea yucatanensis ( Crosse and Fischer) CAMPECHE: (San Geronimo. Type locality, Fisher and Cross, 1890: 240). HYDROBIIDAE Pyrgophorus coronatus (Pfeiffer) CAMPECHE: (Pantel Aguada, Champot6n; Uluman Savanna, Rio Champot6n. Bequaert and Clench, 1986: 78). All the Mexican forms of Pyrgophorus have been referred to P. coronatus at one time or another. This complex badly needs further study, which could well show the Mexican forms are recognizably distinct. Helisoma caribaeum ( Orbigny) (AMPECHE: (Yalic Aguada, nr. Champot6n. Bequaert and Clench„ 1936: 66). Tropicorbis orbiculus (Morelet) CAMPECHE: ( Isla de Carmen and Palizada. Type localities, Morelet: 1849: 16); (Laguna de Terminales. Bequaert and Clench, 1986: 66). Tropicorbis obstructus (Morelet) CAMPECHE: ( Isla de Carmen. Type locality, Morelet, 1849: 17 );( Yalic Aguada, Champot6n. Bequaert and Clench, 1986: 68). Tropicorbis maya (Morelet) CAMPECHE: ( Campeche. Type localily, Morelet,.1849:16). 1967 THOMPSON: SNAILS OF CAMPECHE 231 Tropicorbis retuxus (Morelet) CAMPECHE: (Isla de Carmen. Type locality, Morelet, 1849: 17). PHYSIDAE Aplexa s. spiculata Morelet CAMP~CHE: (Pantel Aguada, nr. Champot6n. Bequaert and Clench, 1936: 69); (€ampeche. Type locality, Morelet, 1849: 18). Aplexa spiculata gracilis (Fischer and Crosse) CAMPECHE: 0 nr. Champot6n. Bequaert and Clench, 1936: 70). Aplexa princeps (Phillips) CAMPECHE: (3.5 mi. s. Champot6n. Branson and McCoy, 1965: 11). Aplexa maugeriae (Sowerby) CAMPECHE: (Palizada. Bequaert and Clench, 1936: 69). VERONICELLIDAE Veronicella moreleti (Crosse and Fischer) CAMPECHE: (Isla de Carmen. Fischer and Crosse, 1878: 682). PUPILLIDAE Gastrocopta pellucida (Pfeiffer) CAMPECHE: 7.1 mi. s.w. Campeche; 8.1 mi. s.w. Champot6n. YUCATAN: 1,0 mi, S.S.e. Puerto Telchac; 0.8 mi. n.e. Becanch6n. Gastrocopta riograndensis Sterki CAMPECHE: 8.1 mi. S.W. Champot6n. YUCATAN: 1.0 mi. s.s.e. Puert6 Telchac. Gastrocopta servilis (Gould) CAMPECHE: (Isla de Carmen. Pilsbry, 1916: 70). 232 BULLETIN FLORIDA STATE MUSEUM Vol. 11 Pupisoma dioscoricola (C. B. Adams) CAMPECHE: 11.4 mi. e. Caydl; (Ciudad de Carmen. Branson and McCoy, 1968: 108). QUINTANA Roo: 7.1 mi. n.n.w. Xiatil. TABASCO: Cardenas. YUCATAN: Tik,11; 0.8 mi. n.6. Becanch6n. These specimens were collected by shaking small trees and bushes over a sheet. SUCCINEIDAE Succinea carmenensis Fischer and Crosse CAMPECHE: (Isla de Carmen. Type locality). [Catinella auara (Say) Bequaert and Clench (1936: 65) recorded this species from Pantel Aguada, near thampot6n. The *62:ord *hs based on shell material and must be confirmed, for generic and specific identifcations within this family are dependent on anatomical and histological data.] SPIRAXIDAE Euglandina cylindracea (Phillips) CAMPECHE: 7.2 mi. s. Pixtun; 2:2 mi. s. Pixt6n; ( Ciudad de Carmen. Brans6n and McCoy, 1968: 103); 6.1 mi. s.w. Seybaplaya; 6.2 mi. n.e. Seybaplaya; 7.1 mi. s.w. Campeche; 5.7 mi. e. Campeche; (Campeche. Fischer and Crosse, 1870); 3.6 mi. s. Hopelch6n; 5.1 mi. n.n.w. Dzibalch6n; 5.1 mi. w. Tikinmul; 10.2 mi. e. Escircega. QUINTANA Roo: 7.1 mi. n.n.w. Xiatil. YUCATAN: 0.8 mi, n.e. Becanchdn; Uxmal; 19.1 mi. s.s.e. Uman; 7.0 mi. s.s.e. Uman. This species is most commonly associated with semi-xeric and mesic forests. Specimens from near Escicega show it is able to exist in tropical rain forests, but populations are sparse in this biome. Euglandina carmenensis (Morelet) CAMPECHE: 7.1 mi. s.w. Campeche; 2.2 mi. s. Pixt,in ( Ciudad de Carmen. Type locality, Morelet, 1849: 14). 1967. THOMPSON: SNAILS OF CAMPECHE 233 [Euglandina ghiesbreghti (Pfeiffer). Branson and McCoy (1965: 5) record this and the following species. from_.Champot6n, Campeche..Both are montain forms known from limited areas in Chiapas and Oaxaca respectively. The different ecological and climatic conditions in Campeche make their occurrences there unlikely. The specimens they cite could not be located to confirm the identificatighs.1 [Et,glandina sowerb!/ana (Pfeiffer). See previous species,] Euglandina cuthingi ( Beck) CAN{PECHE: (17.2 mi. s. Champot6n. Branson and McCoy, 1965: 4). Streptostula This genus of about 60 species distributed through Central America and Mexico is divided into five subgenera. These subgenera were originally defined On the basis of shell characters, but becailse of the number and diversity of the species involved, the distinctions be- tween the subgenera by shell characters is not always clear. Baker (1941, 1948) redefined three of the subgenera by means of anatomical characters, but his system of classification is only partially satisfac- tory because of the small number of species whose anatomies are known. The first anatomical studies of Streptostyla were made by Strebel (1878: 16, 22-23) who described. the soft parts of S. streptostyla (Shuttleworth) (as S. coniformis), S. nicoleti (Shuttleworth) and S. physodes (Shuttleworth). Baker ( 1943) described the soft parts of S. streptostyla (genotype of Streptostyla), S. nicoleti (genotype of Eustreptostyla), S. physodes, S. lymneiformis (Shuttleworth),. S.. j. iTrigua ( Shuttleworth) and S. i. quirozi Strebel. Baker placed S. physodes and S. lymneiformis in the subgenus Rectoleacina,because of the similarities of their shells,to this otherwise Cuban group. S. irrigua he placed in Chersomitra because of similarities of its shell to S. nigricans (Pfeiffer) (genotype of Chersomitra). He separated Cher- somitra from Streptostyla only as a "section" (- species group) be- cause of the anatomical similarities of the species he examined. While studying the relationships of the Campeche species of Streptostyla, I dissected two specimens of S. nigricans to verify the identity of Chersomitra. The characters of the epiphallus and penis proved similar to those Baker described for S. physodes and S. lyni- neiformis, and quite different for those he reported for S. irrigua. This necessitates the following systematic changes: (1) Chersomitra in- 234 BULLETIN FLORIDA STATE MUSEUM Vol. 11 cludes S. nigricans, S. physodes and S. lymn€iformis, and is used in place of Rectoleacina for mainland species. (2) Streptostyla includes S. streptostyla and S. irrigua as well as S. uentricosula ( Morelet) and S. meridana (Morelet) as discussed below. (8) The subgeneric relation- ships of most of the other species of Streptost!/la usually placed in the typical subgenus or. Chersomitra remain uncertain, for convergent evolution in shell characters has occured in both groups. (4) Rect- oleacina is again restricted to Cuba, and its anatomy and relationships to mainland taxa remain unknown. The subgenera that are known anatomically may be distinguished as follows: Streptostyla: epiphallus absent; penis simple, without accessory appendages; salivary glahd forming a complete ring around the esophagus. Eustreptostula: epiphallus present; penis simple, lacking accessory appendages; a "stimulator" presents on inside of penis wall; salivary gland incomplete across ventral surface of esophagus. Chersomitra: epiphallus present; penis with a single lateral ap- pendage; salivary gland forming a complete ring around the esopha- gus. Peteniella and Streptostylella are still unknown anatomically. Streptostyla nigricans (Pfeiffer) CHIAPAS: 3.5 mi. s. Ray6n, 5500' (two specimens dissected). Sides of foot and snout bright yellow bordered dorsolaterally on each side of body by a broad black band that is continuous over dosal surface of tail. Nape with a narrow bright yellow middorsal stripe that is continuous to snout. Mantle collar dull yellow. Outer wall of lung black fading into dark brown near collar. Rest of mantle light pinkish yellow. Tail pointed, rounded above, without distinct pedal groove. Lung about twice as long as wide. Minor venations of lung distinct. Kidney T-shaped, almost triangular (fig. 1, F). Pericardium about 0.8 times length of kidney base. Esophagus entering dorsal side of buccal bulb anterior to radula. Salivary gland continuous around esophagus (fig. 1, A). Right occular retractor muscle passing through genital atrium. Genital atrium connected to body wall by a relatively long slender neck (Ag. 1, C). Ovotestis consisting of six lobes with 8-9 alveoli per I lobe (not illustrated). Spermatheca pressed against uterus by aorta, 1967 THOMPSON: SNAILS OF CAMPECHE 235 and resting behind prostate. Albumen, gland bright orange in color, very large, elongate, sausage-shaped ·with a broad furrow in baso- columellar side where it rests against intestine. Prostate relatively large, about % length of uterus and closely appressed; located near top of enlarged uterine folds. Vas deferens enlarged into, an epiph- allus about half way between prostate and penis. Penial retractor muscle long and slender, attached to diaphram over salivary gland, enveloping epiphallus for a short distance above penis. Penis long and moderately stocky, with a large diverticulum located about ¥4 of distance below epiphallus. Inside of diverticulum with numerous oblique longitudinal folds. Inside of penis with large opposing longi- tudinal ridges. Radula ( one specimen examined) containing 60 tradsverse rows of teeth, with 56 teeth per row. Inner tooth longest, or only slightly shorter than next tooth, about 175 B long. Following teeth gradually decreasing in size through outer marginal tooth, which is about 30 B long. Cusps on teeth simple, dagger-shaped. Ribbon 7.6 mm. long. Although fundamentally similar in anatomical characters to S. physodes and S. lymneiformis, S. nigricans is very distinct from these two species by the large size of its albumen gland and by the long neck that connects the genital atrium to the body wall. The extension of the right occular retractor muscle through the genital atrium in S. nigricans has not been recorded from Other species of Streptostyla. Streptostyla ventricosula (Morelet) w Glandina ventricosula Morelet, 1849; Testac. Noviss., I: 15. (Type locality: Merida, Yucatan). Streptost!/la ventricosula (Morelet), von Martens, 1892; Biol. Centr. Amer., Moll.: 97; pl. f, fig. 20.- Pilsbry, 1907; Man. Conch., Ser, II, 19:158; pl. 80, figs. 87, 89. Streptosti/la vucatanensis Pilsbry, 1907; Man. Conch., Ser. II, 19: 158-154; pl. 80, figs. 90, 91. (Type locality: Tekanto, Yucatan). Streptost!~da yucatanensis var. distorta Pilsbry, 1907; Man. Conch., Ser. II, 19: 154; .pl. 30, fg. 92. (Type locality: Tekanto, Yucatan). CAMPECHE: 7.2 mi, s. Pixtdn; 6.1 mi. s.w. Seybaplaya; 6.2 mi. n.e. Seybaplaya; 7.1 mi. s.w. Campeche; 5.7 mi. e. Campeche; (32 mi. e. Campeche. Branson and McCoy, 1963:.103); 8.4 mi. w. Ich-Ek; 8.6 mi. s. Hopelch6n; 5.1 mi. w. Tikinmdl; 5,1 mi. n.n.w. Dzibalch6n; 10.2 mi. e. Dzibalch6n. YUCATAN: 19.1 mi. s.s.e. Uman; 0.8 mi. n.e. Becanchdn. This species is primarily found in semi-xeric and mesic forests, and is known only from Yucatan and Campeche, where it usually occurs with S. m. meridana. 236 BULLETIN FLORIDA STATE MUSEUM V61. 11 I cannot separate S. yucatanensis Pilsbry satisfactorily from S: uentricosula ( Morelet). Pilsbry ( 1907: 153-154) {recognized S. yucd- tatiensis on the basis of a deep6r .sutur6,-a narrower subsutural clear zone, a more cylindrical last wborl, and a weaker columellar fold. The specimens before me show all intermediate stages between these two forms. The variety distorta Pilsbry was based upon an aberrant specimen, and merits no further recognition as a taxonomic entity. Animal (two specimens dissected from 8.4 mi. w. Ich-Ek) similar to that of S. streptostyla as described by Baker ( 1943: 6) except: Ani- mal uniformly dark gray. Lung unmarked, uniformly gray. Kidney triangular and very long, about twice length of oblique base (fig. 1, G). Pericardium about 0.6 times length of kidney. Salivary gland continuous around esophagus (fig. 1, B). Right occular retractor mus- cle passing inside from reproductive system. Genital atrium attached directly to body wall, without a connecting neck, (fig. 1, D). Sperma- theca columellar, resting at base of albumen gland. Albumen gland small, sausage-shaped, weakly compressed. Prostate very small, pri- marily restricted to posterior side and middle of uterus (fig. 1, ED. Vas deferens slightly enlarged near middle but not forming a distinct epiphallus. Penial retractor muscle attached to inner wall of diaphram, enveloping vas deferens for about % of muscle length. Penis long, but moderately stocky, without accessory appendages or a "stimu- lator". Radula (one specimen examined) containing 50 transverse rows, with 54 teeth per'whorl. Inner tooth 90 p long. Following four teeth rapidly increasing in size. Fifth tooth about 150 F long. Remaining teeth gradually decreasing in size through last tooth, which is about 24 p long. Ribbon 5.0 mm. long. FIGURE 1. Anatomy of various species of Streptost!/la. A. S. nigricans (Pfeiffer). Salivary gland with portions of esophagus and salivary ducts. B. S. uentricosula (Morelet). Salivary gland with portions of esophagus and salivary ducts. m 0 3 91 P o S. nigricans (Pfeiffer). Reproductive system. S. ventricosula (Morelet). Reproductive system. S. ventricosula (Morelet). Ventral view of portion of reproductive system showing restriction and relationships of the prostate. S. nigricans (Pfeiffer) Kidney and associated structures. S. ·ventricosula (Morelet). Kidney and associated structures. , I. S. meridana (Morelet). Portion of the reproductive system showing relationships of the prostate. Scales equal 2 mm. 1967. THOMPSON: SNAILS OF CAMPECHE 237 EPIPHALLUS UTERUS SALIVARY GLAND PENIAL RETRACTOR PROSTATE I ESOPHAGUS ALBUMIN - APPENDIX GLAND -~ u ... - VAGINA -L.PENIS B SPERMATHECA~ -1*-PROST « At-BUMIN_ PROSTATE VAS DEFERENS GUND PENIS E D ~ PRIMARY URETER '*S,t:*. KIDNEY- UTERUS PROSTATE---.- F H G 238 BULLETIN FLORIDA STATE MUSEUM Vol. 11 This species belongs in the subgenus Streptosty14 because of the characteristics of its reproductive system. It is anatomically peculiar because of the small size and restriction of the prostate. Streptostyla m. meridana C Morelet) Glandina meridana Morelet, 1849, Testac. Noviss., I: 15. (Type locality: Merida, Yucatan). Streptostula meridana (Morelet), Martens, 1892; Biol. Cent. Amer.: 101; pl. 5, fig. 25.-Pilsbry, 1907; Man. Conch. ser. II, 19: 154-155; pl. 30, figs. 93-96. Salasiella meridaensis Branson and McCoy, manuscript name; Type: UMMZ 210557. Streptostula mastini Branson and McCoy, 1962; Naut., 76: 8, pl. 2, figs. la, lb. (Type: UMMZ 210557. Type locality: 19 miles east of Merida, Yucatan). Sansiella tottecorum Branson and McCoy, manuscript name; Type: UMMZ 210558. Streptostyla toltecorum Branson and McCoy, 1962; Naut., 76.8-9, pl. 2, figs. 2a, 2b. (Type: UMMZ 210558. Type locality: 5 miles east of Campeche, Campeche). CAMPECHE: 0.9 mi. s.w. Champot6n; 8.1 mi. s.w. Champot6n; (Ciudad de Carmen; 5-11 mi. e. Campeche. Branson and McCoy, 1968: 105); 6.1 mi. s.w. Seybaplaya; 6.2 mi.· n.e. Seybaplaya; 7.1 mi. s.w. Campeche; 5.7 mi. e. Campeche; 5.1 mi. w. Tikinm61; 3.4 mi. s. Cayal; 2.2 mi. s,· Pixtun; 8.4 mi. w. Ich-Ek; 8.6 mi. s. Hopelchin; 5.1 mi. n.n.w. Dzibalchdn; 7.2 mi. s. Pixtfin; 19.2 mi. e. Silvitdc. QUINTANA Roo: 7.1 mi. n.n.w. XiatiI. YUCATAN: 7.0 mi. s.s.e. Uman; 1.0 mi. s.s.e. Puerto Telehae; 0.8 mi. n.e Becanch6n. This species is found most commonly in semi-arid and mesic habi- tats, where it occurs in second growth as well as virgin forests. Only rarely is it found in rain forests. S. meridana was adequately described and illustrated by Pilsbry (1907: 154-155; pl. 80, Bgs. 98-96). My measurements of 50 specimens from Campeche, Quintana Roo, and Yucatan are: length, 8.2-10.4 mm.; width, 8.4-4.8 mm.; length of aperture, 4.8-6.1 mm.; length/width, 2.27-2.48; length/aperture, 1.59-1.78; 4.6-5.5 whorls. Streptostyla maslini Branson and McCoy and Streptostyla tolte- corum Branson and McCOy do not differ from typical S. meridana (Morelet). The measurements and proportions given by Branson and McCoy (1962: 8-9) fall within the ranges of variation for S. meridana given by Pilsbry (1907: 154-155), and which I have found in my popu- lation samples. Branson and McCofs illustrations have little similarity 1967 THOMPSON: SNAILS OF CAMPECHE 239 to the type specimens they represent. Figures of these same specimens (fg. 2, A-D) drawn with the aid of a camera lucida fall well within the variations illustrated for S. meridana by Pilsbry (1907: pl. 80, Bgs. 93-96). Branson and McCoy originally assigned their material in manu- script to Salasiella meridaensis new species, and Salasiella tottecorum, new species. After they had deposited their material in various --I --i A B D FIGURE 2. HOLOTYPES of two nominate forms of Streptost!/ta meridana (Morelet). A, B. Streptostula toltecorum Branson and McCoy (UMMZ 210555). C, D. Streptostyla mastini Branson and McCoy (UMMZ 210557). Scale equals 2 mm. museums under their manuscript names, they realized their specimens belonged in the genus Streptostyla. In their descriptions (1962) of S. maslini and S. toltecorum they apparently did not compare this ma- terial adequately with all the numerous forms of Streptostyla. Two specimens dissected froih 5.1 mi. n.n.w. Dzibalthdn are similar to S. streptostyla except: Animal uniformly light gray. Lung unmarked, uniformly gray. Kidney triangular, about twice as long as oblique base. Pericardium about 0.6 times length of kidney. Salivary glands continuous around esophagus. Right occular retractor muscle passing inside from genitalia. Genital atrium attached directly to body wall, without a connecting neck (fig. 1, H, I). (Only female half of system illustrated because penis of each dissected specimen was everted and not in usual position). Spermatheca columellar, im- bedded at base of albumen gland. Albumen gland elongate sausage- 240 BULLETIN FLORIDA STATE MUSEUM Vol. Il shaped, slightly compressed. Prostrate about- 35 length of uterus, re- stricted primarily to outer surface, and middle of uterus. Vas deferens slightly enlarged near middle. Penial retractor muscle attached to inner wall of diaphram, enveloping vas deferens for about % of mus- cle length. Penis long, moderately stocky, without accessory appen- dages or stimulator. Radula (1) cobtaining 45 transverse rows of teeth, with 40 teeth per row. Inner tooth about 75 F long. Following three teeth rapidly increasing in size. Fourth tooth about 110 F long. Remaining teeth gradually decreasing in size through last tooth, which is about 14 B long. Ribbon 8.7 mm. long. The characters of the reproductive system show this species is closely related to S. uentricosula. Anatomically it differs from this species in its proportionally larger prostrate, which is located primar- ily on the outer surface of the uterus. Streptostyla meridana subsp. GUATEMALA, DEPT. PETEN: ( San Benito; 7.9 m. s.w. San Benito; Flores; 25 mi. s. Flores; Santa Teresa; Puerto Nuevo; 2 km. s. Puerto Neuvo; Santa Ana; San Andres; La Libertad; Tikal; Laguna Sotz; 6 mi. n. Laguna Sotz; 10 mi. n. Laguna Sotz; Laguna Perdida; 3 mi. n. Laguna Perdida; 6 mi. s. Laguna Perdida; Paso Caballo; 1 mi. n.w. Paso Caballo; 5 mi. n. Paso Caballo, 6 mi. e. Paso Caballo. UMMZ). QUINTANA Roo: 4.0 mi e. Xpujil, Campeche. The Guatemalan localities are for specimens in the University of Michigan Museum of Zoology reported by Goodrich and van der Schalie (1987:24). My measurements of 50 specimens are: length, 10.8-11.9 mm.; width, 4.3-5.0 mm.; aperture length, 5.8-7.0 mm.; length/width, 2.24-2.48; length/aperture, 1.59-1.75; 5.0-5.5 whorls. These specimens are intermediate in size between S. m. meridana and the larger, more robust S. m. cobanensis Tristam. Material from the intermediate areah of Campeche, Peten and Alta Verapaz is not sufficient to determine whether the size differences between these three forms are disjunct or clinal. FERUSSACHDAE Cecilioides consobrinus primus (De Folin) CAMPECHE: 8.1 mi. s.w. Champot6n. YUCATAN: 0.8 mi. n.e. Becanch6n. 1967 THOMPSON: SNAILS OF CAMPECHE 241 ACHAT[NIDAE Lamellaxis gracilis (Huttoh) CAMPECHE: 8.1 mi. s.w. Champot6n; 0.9 mi. s.w. Champot6n; 6.1 mi. s.w. Seybaplaya; 6.2 mi. n.e. Seybaplaya; 7.1 mi. e. Campeche; 3,6 mi. s. Hopel- chdn; 5,1 mi. n.n,w. Dzibalch,~n. Subulina octona (Brukuidre) CAMPECHE: (Campeche. von Martens, 1898: ·299); (Ciu(lad'de Carmen. Branson and McCoy, 1963: 107) SYSTROPHIIDAE Miradiscop maya ( Pilsbry) YucATAN: 0.8 mi. n.e. Becanchdn. Miradiscops haplococ/dion new species ( Bg. 3, A-C) TYPE LOCALITY. 8.1 miles southwest of Champot6n, Campeche. TypE: UF 19058; collected 14 June, 1965 by Fred G, Thompson. PARATYPES: UF 19059 (2); same data as type. DESCRIPTION. Shell depressed-conical. Openly umbilicate, umbilicus contained 3.7 times in major diameter. Nearly transparent. Whitish, with a silky luster. About 5 whorls (4.9) that gradually increase in size. Whorls evenly rounded. Suture weakly impressed, narrowly margined. First whorl smooth, with very faint, fine radial striations. Following whorls with fine, closely spaced, oblique axial striations that are continuous over the periphery of the whorls and into the umbilicus; slightly coarser near .suture. Very faint, fine growth wrin- kles along suture between striations. No spiral sculpture present. Aperture oblique, lying at about 80° to axis; subround; preceding whorl incised into about ¥4 of aperture. Peristome thin, incomplete; columellar lip slightly reflected near umbilicus. Major diameter, 2.37 mm.; minor diameter, 1.99 mm.; height of shell, 1.37 mm.; aperture 0.89 mm. high; 0.96 mm. wide. 242 BULLETIN FLORIDA STATE MUSEUM Vol. 11 - - tr-.r- -- -, - ---- I ,- ,\ 1 - -4-«ili...-i,Jf-- , ---,2': A D - - 1- /4 . 1 1,/1 -1/ 1 11 ,0 '' 2.l,.,2 , '- 44 Ch ':'114 '.15.'F --.,-C;'P,4 1 '.3 U..1- & -Il-I111-3 '' 1 - -' 1 ---1 ,"- E B /1, , -1 1,~-,r\TI - 14 -1 I , '1'F-~M- - If ----IA1 : 1 ·% &-Illr 1 1-*(181)/-tr- -*- 1 . 2-'' -3 '.I,4.hill- -~-i-- '' J 11 - ,/ 1 Il ./-1 , 2 -'el , C 4.,64+14<592-9' F FIGURE 3 A-C. Miradiscops haplocochtion new species, TYPE ( UF 19058). 8.1 miles s.w. Champot6n, Campeche. D-F. Hawaiia- minuscula C Binney). 8.1 miles s.w. Champot6n, Campeche. 1967 THOMPSON: SNAILS OF CAMPECHE 243 This species is most similar to M. maya (Pilbsry), but differs by its whitish color, by having a relatively larger umbilicus, and by having a depressed conical spire. M. maya is pale yellow in color, has an umbilicus that is contained slightly more than 4 times in the major diameter, and has a depressed dome-shaped spire. The latter species is also smaller and has only four whorls, but this may be only a matter of individual sizes (Pilsbry, 1919: 216). I name this species with some hesitation, but its whitish color and larger umbilicus do not allow it to be identified with any of the other named species of Miradiscops. The type specimens were found under a broken block of caliche near a black mangrove swamp. ZONYODAE Habroconus pittieri (Von Martens) (AMPECHE: 5.1 mi. n.n.w. Dzibalch6n; 8.1 mi, s.w. Champot6n; 7.2 mi. s. Pixtdn; 19.2 mi. e. Silvituc. QUINTANA Roo: 4.0 mi. d. Xpujil, Campeche; 7.1 mi. n.n.w. Xiatil. YUCATAN: 0.8 mi. n.e. Becanch6n. These specimens are similar in all characters of the description and illustrations given by von Martens (1892: 121), except that they have slightly finer sculpture. In this respect they are similar to H. elegantula (Pilsbry), but the spire is not as high nor do they have as many whorls as that species. Guppya gundlachi ( Pfeiffer) CAMPECIE: 8.1 mi. s.w. Champot6n. QUINTANA Roo: 4.0 mi. e. Xpujil, Campeche; Cozumel Island, 1.5 km. n.n.e. San Miguel. Hawaiia minuscula subsp. ( flg. 3, D-F) CAMPECHE: 8.1 mi. s.w. Champot6n; 7.2 mi. s.w. Pixtlin. The specimens from Campeche are slightly more obese than any ' of the subspecies described from farther . north, but my material is inadequate to determine the geographical distribution of this varia- tion. 244 BULLETIN FLORIDA STATE MUSEUM V61. II ORTHALICIDAE Orthalicus princeps (Sowerby) CAMPECHE: (29.7 mi. s. Campeche. Branson and McCoy, 1965:8); (82 mi. e. Campeche. Branson and McCoy, 1963: 106); 3.4 mi. s. Caydl; 8.4 mi. w. Ich-Ek; 8.6 mi. s. Hopelch6n; 5.1 mi. n.n.w. Dzibalch6n; (15 mi. s. Champo- t6n. Bequaert and Clench, 1986:64). Bulimulus unicolor (Sowerby) Bulinus unicolor Sowerby, 1838; Proc. Zool. Soc:: 78. Butimus umbraticus Reeve, 1849; Conch. Icon. pl. 77, fig. 559. Butimus ignauus Reeve, 1849; Conch. Icon.: pl. 77, fig. 562. Bulimus petenensis Morelet, 1852; Testac. Noviss., II: 10. Bulimulus sanmiguelensis Richards, 1937; Proc. Amer. Philos, Soc., 77: 253-254; pl. 4, fig. 6. CAMPECHE: 17.2 mi. s. Champot6n (USNM 635742); 0.9 mi. s.w. Champot6n; 6,'1 mi. s.w. Seybaplaya; 6.2 mi. n.e. Seybaplaya; 7.2 mi. s. Pixtiln; 2.2 mi. s. Pixmn; Campeche (USNM 467448); 5.1 mi. w. Tikinmitli · 16.8 mi. s. Tenabo; 8.6 mi. s. Hopelchdn; 3,4. mi. s. Cayal; 5.1 mi, n,n.w, Dzibalchdn; 10.2 mi. e. Escdrcega; 19.2 mi. e.-Silvitue. CHIAPAS: (USNM 162504). QUINTANA. Floo: CozumeI Island, 1.5 km. n.n.e.. San Miguel; 7.1 mi. n.n.w. Xiatil; 2.8 mi. s.s.e. Xiatil; 4.0 nYi. e.- Xpujil. TABASCO: (USNM 10555). YUCATAN: Chichen Itza (USNM 482848, 467451, 251660); San Ignacio (ANSP 256918); Merida; Uxmal; 0.8 mi. n.e. Becanch6n; 10.0 mi. n.e. Becanch6n; 7.0 mi. s.s.e. Uman; 1.0 mi. s.s.e. Puerto ·Telchac. BRITISH HONDURAS: w. of Gales Point (USNM 882717.); Benque Viejo (USNM 194128); Benque Viejo Riv., 1 mi. from Cayo (USNM 382788); Belize Riv. (USNM 41167). GUATEMALA, DEPT. PETEN: "Peten" (ANSP 25629 - paratype of B. petenensis Morelet); Paso Caballo (ANSP 177303); Flores (ANSP 177285); Puebla Nueva (USNM 428983); Remate (USNM 882778); Id. in Lake Eckixil (USNM 428984); Uaxactdn (USNM 882988). GUATEMALA, DEPT. ZACAPA: around Zacapa (USNM 426005, 426015, 426017). HONDURAS, CHIQUIMULA PROv. Between Jocotan and Jumusna ( USNM 426011, 426012, 426013). This highly plastic species undergoes considerable geographic and ecological variation that has resulted in at least fve synonyms. 1967 THOMPSON: SNAILS OF CAMPECHE 245 The group was most recently reviewed by Pilsbry (1897: 50-58), who presented descriptions, based upon type material, of all of the forms named at that time. These forms may be briefy diagnosed as follows: B. unicolor - a medium size#, conical form, 14-19 mm. long with about 5-6 whorls, weak incremental sculpture, no spiral sculp- ture, and a thin shell with a corneous-brown periostracum. B. umbraticus - similar to B. unicolor, but transparent white streaked with pale brown near the apex. B. ignaous - similar to B. unicolor, but a small form about 9 mm. long, and with about 7 whorls (?). B. petenensis - similar to B. unicolor, but with alternating light and dark streaks on the periostracum. B. sanmiguelensis - similar to B. unicolor, but with nearly flat whorls united by a relatively superficial suture. Since they were originally proposed, these named forms.have been assigned to different taxonomic ranks by various authors. Pilsbry (1897: 50-58) followed previous authors in his treatment of this group. He recognized umbraticus as a separate species, petenensis .as a geographic race of unicolor, and ignauus as a "variety" of B. dysoni (Pfeiffer), though doubtfully so. More recently Richards (1987: 258- 254) described sanmiguelensis, and Harry (1950: 12-15) elevated ignauus to specific status. Material I have examined indicates that the size of the shell varies with the climatic areas of the Yucatan Peninsula as follows ( Eg.4): Dry coastal areas of Campeche and Yucatan, and the Polochic Val- ley of Guatemala - (ignaous) size small, 9.0-10.0 mm. long, 0.50-0.62 times as wide as long; aperture 0.44-0.58 times length of shelli 4.3-5.1 whorls. Mesic deciduous forests of Campeche and Yucatan - (inter- mediate sized form) 10.0-12.6 mm. long; 0.56-0.64 times as wide as long; aperture 0.45-0.57 times length of shell; 4.7-5.7 whorls. Moist deciduous and eyergreen forests of Yucatan, Quintana Roo, British Honduras and Peten - (unicolor, petenensis) modera- tely large forms 12.3-16.5 mm. long; 0.48-0.69 times as wide as long; aperture 0.45-0.52 times length of shell; 5.5-6.1 whorls. Wet rain forests. of Quintana Roo and British Honduras - (uni- , color, sanmiguelensis) size large, 14.8-18.7 mm. long; 0.48-0.59 246 BULLETIN FLORIDA STATE MUSEUM Vol. 11 times as wide as long; aperture 0.44-0.51 times length of shelli 5.5-6.8 whorls. Distinctions based on size between any of these forms are not tenable because of the continuous series of intergradations that occur ( fig. 5). There is still some question about the identity of Bulimus 0 9.0-10.0 mm. 0 0 10.0-12.6 rom. A 12.3- 16.5 mni 0 IA 0 I 14.8-18.7 mm. 0 0\ A r O? p A m AA FIGURE 4. The geographic distribution of Bulimulus unicolor ( Sowerby) in the Yucatan Penihsula and adjacent areas, showing the distribution of size forms throughout the region. Open circles represent a small form 9.0-10.0 mm. long. Solid circles represent a larger form 10.0-12.6 mm. long. Triangles represent a larger form 12.8-16.5 mm. long. Squares represent large specimeins 14.8-18.7 mm. long. 1967 THOMPSON: SNAILS OF CAMPECHE 247 10 . W H O R LS AP ER TU R E LE N G TH W ID TH of S H E LL . 9 .. . 8. • 7 - :4 •. ..4.:.. 6 •• •I. . ...L 5. . 9 8. I. ..7. .: 6. •.. ......:... ...5 . .. . 4 . - 6 • . .-. ...I.... 5 : ••I -f '- 5. ..:. ...4 4. 8 9 10 11 1213141516 17 18 19 LENGTH of SHELL FIGURE 5. Graph showing the relationships between the length of the shell, and the width of the shell, the length of the aperture and the number of whorls in Butimulus unicolor (Sowerby). No breaks ih the trends oc- cur that would allow the recognition of more than one form on the basis of tliese ratios. 248 BULLETIN FLORIDA STATE MUSEUM Vol. 11 ignauus. In his original account Reeve (1849) stated that it had seven whorls, but no specimen corresponding to its size has subsequently been found with as many whorls. Harry (1950: 13) apparently worked on the assumption that Reeve's short description and figure were in error or that the type was based upon an abnormal specimen, and assigned the small form discussed above to ignaous. B. petene,isis appears to be only a geographic color variation of unicolor, and is confined to the Peten region of Guatemala. Some populations found in the same region consist entirely of the form unicolor, and most series of petenensis also have some specimens that can be identified as unicolor. B. umbraticus appears to be only an extreme variation of the petenensis color form. The characteristic of the flat whorls that Richards used to separate B. sanmiguelensis is also untenable, for this character varies widely among different series of specimens from over the whole range of the species. Bulimus inermis Morelet, 1851, is probably also synonymous with B. unicolor. The type specimen is 9.0 mm. long, 4.0 mm. wide, has an aperture 3.0 mm. long, and 7 whorls ( Fischer and Crosse, 1878: 550). A single specimen that I collected from 7.0 mi. s.s.e. Uman, Yucatan, and two specimens from Tabasco (USNM 10555) dpproach these pro- portions, but do not have as short an aperture or as many whorls. B. unicotor may be properly diagnosed as follows: a highly varia- ble Central American species of. the subgenus Bulimulus, 9.0-18.7 mm. long; 0.48-0.68 times as wide as long; aperture 0.44-0.56 times length of shell; 4.9-6.8 whorls; postembryonic sculpture consisting of incremental striations only; generally unicolor or various hues of brown, but may be streaked or shaded; aperture oblique, but nearly straight edged in lateral profile. This species probably intergrades with B. corneus (Sowerby) which occurs farthur south but sufficient material from Guatemala and Honduras to determine this is not available. Drymaeus sulphureus (Pfeiffer) CAMPECHE: (Ciudad de Carmen; 16 mi. e. Campeche. Branson and McCoy, 1968: 106). Drymaeus tropicalis (Morelet) CAMPECHE: 5.1 mi. n.n.W. Dzibalchdn; 3.6 mi. s. · Hopelchdn; 5.7 mi. e. Campeche; (5-11 mi. e. Campeche; 32 mi. e. Campeche. Btanson and McCoy, 1968: 106); Edzna; (Campeche. Type locality, Morelet, 1849:9); 19.2 mi. e. Silvituc. 1967 THOMPSON: SNAILS' OF CAMPECHE 249 QuINTANA Roo: .4.0 mi. e. Xpujil. YUCATAN:- 0.8 mi. n,e, B6canchin; 19,1 mi. s,s,e. Uman. This species appears to be common in semi-mesic, mesic and. rain f6rests within its range. It is an abundant snail, judging fr6m the number of dead shells in recently cleared areas. Drymaeus dominicus (Reeve) CAMPECHE: 19.2 mi. e. Silvituc; (11 mi. e. Campeche. Branson and McCoy, 1965: 8). QUINTANA Roo: 4.0 mi. e, Xpujil, Campeche. Drymaeus multitineatus (Say) CAMPECHE: (11 mi. e. Campeche. Branson and McCoy, 1965: 8). Drymaeus serperastrum (Say) CAMPECHE: 7.1 mi. s.w. Campeche. A single dead shell was found in a semi-xeric scrub forest. UROCOPTIDAE Microteramus concisus (Morelet) CAMPECHE: 7.1 mi. s.w. Campeche; 6.1 mi. s.w. Seybaplaya; 6.2 mi. n.e, Seyba- playa; 0.9 mi. s.w. Champot6n; 2.2 mi. s. Pixtlin; 5.7 mi. e. Campeche; 5.1 mi. w. Tikinmul, S.6 mi. s, Hopelch-6n; 5.1 mi. n.n.w. Dzibalch6n; 6.1 mi. n. Dzibalchdn; 4.3 mi. ·n. Tenabo; 7.2 mi. s. Pixtdn; (5-11 mi. e. Campeche. Branson and McCoy, 1968: 107). This species is found in xeric and mesic habitats, and generally is common where it is found. Brachypodella dubia (Pilsbry) (Bg..6, C-E) Cylindrella speluncae var. dubia Pilsbry, 1891, Proc. Acad. ·Nat. Sci. Phil.: 316; pl. 15, figs. 14, 14a. (Type locality: Labna, Yucatan). Ct/Zindrell9 speluncae Pfeiffer, Pilsbry, 1891, Proc. Acad. Nat. Sci. Phil,: 815, pl. 15, figs. 15, 15a. Brachypodella spetuncae (Pfeiffer), Pilsbry,· 1904, Man. Conch., Ser. II, 16: 70-71, pl. 6, figs. 18, 14. - Bequaert and Clench, 1988, Pub. Carnegie Inst. Wash., 250 BULLETIN FLORIDA STATE MUSEUM Vol. 11 (481): 585. - 1936, Pub. Carnegie Inst. Wash., (457): 65. - 1938, .Pub. Carnegie Inst. Wash., (491): 258. - Richards, 1937, Proc. Amer. Philo. Soc., 77: 254. - Harry, 1950: Occ. Pap. Mus. Zool. Univ. Mich., (524): 16. - Branson and Mc(Joy, 1965: Univ. Colorado Stud. Biol., (18): 9. CAR{PECHE: 19.2 mi. e. Silvituc (1); 7.2 mi. s. Pixtun (6); 6.1 mi. s.w. Seyba- playa (3); 6.2 mi. n.e. Seybaplaya (1), 7.1 mi. s,w. Campeche (18); 5.1 mi. n.n.w. Dzilbalch6n (49); 5.1 mi. w. Tikinmul (4). QUINTANA Roo: 7.1 mi. n.n.w. Xiatil (6); Cozumel Island, 1.5 km. n.n.e. San Miquel (29). YUCATAN: 10.0 mi. n.e. Becanch6n (1). This species is 06mmon and generally distributed throughout Campeche and Yucatin. It is infrequently collected because it usually lives deep in rock crevices and piles of broken rock. Shell dull; light beige; aperture and peristome white. Imperforate. Subtranslucent. Elongate cylindric-conical. Spire attenuate. Upper 4&-36 of spire increasing uniformly in size; lower portion of shell nearly uniform in diameter, decreasing slightly at last two whorls. Spire usually decollate at maturity. 19.7-28.2 whorls in mature shells with complete spires; 11.8-18.4 whorls below apical plug. Whorls moderately convex; periphery lying above middle of whorl. Aperture extending forward and down on a 16ng neck that is about one half as long as diameter of sheil. Neck with a strong basal ridge. Aperture nearly circular, slightly wider than high. Peristome moderately ex- panded; widest in basocolumellar region; 0.2-0.8 mm. wide along columellar margin, or about one ffth diameter of aperture. Apertufe broadly angulate in basal and outer margins. 3.2-8.5 embryonic whorls, nearly uniform in size; second embryonic whorl 0.5-0.6 mm. wide. Embryonic whorls with very fine axial threads that are 0.02-0.05 mm. apart. Following whorls sculptured with relatively strong axial ribs that are more closely spaced on the spire than on lower whorls; 12-20 ribs on antipenultimate whorl. Ribs oblique and very weakly sigmoid; slightly higher than wide. Interspaces nearly smooth; with occasional faint axial striations. Internal axis thin, rounded, weakly spiral. Length of shell with complete spire, 12.1-16.1 mm.; length of shell FIGURE 6 A, B. Choanopoma andrewsae (Ancey). 5.1 miles n.n.w. Dzibalch6n, Campeche. A. Female. B. Male. C-E. Brachypodeth dubia (Pilsbry). 5.1 miles n.n.w. Dzibalch6n, Campeche. F-H. Brachypodetta speluncae (Pfeiffer). Knoll on road to Santa Ana, 2 km. s, Puebla Nueva, Dept. Peten, Guatemala. (UMMZ 64538). 1967 THOMPSON: SNAILS OF CAMPECHE 251 /1/'TAB'.er BV 4#k /1 C-/2/l' , -- 4 V E Lf G <19 H 252 BULLETIN FLORIDA STATE MUSEUM Vol. 11 to apical plug, 10.0-12.8 mIn.; width of shell, 2.0-2.3 mm.; width of aperture including peristome, 1.6-2.0 mm. The number of ribs on the lower whorls is variable. Though char- acteristic of difrerent populations, the variation shows no geographic or ecological pattern. Other features of the sculpture and the structure are nearly constant. B. dubia is similar to and may be only subspecifically distinct from B. speluncae, with which it has been confused. It is distinguished by its low number of whorls below the apical plug, by its low number of ribs per whorl, by its strong, low axial ribs, by its elongate cylindric- conical shape and by its narrow peristome. This species has been confused with B. speluncae because of the lack of comparative material of the latter species in American collec- tions. Pilsbry (1891: 816) recognized Cylindrella speluncae var. dubia on the bases of an aberrant population of small individuals from Labna, Yucatan. Later (1904: 70) he relegated dubia to the synonymy of speluncae because of a lack of satisfactory differences between dubia and other Yucatan populations of Brachypodella that he identi- fled as speluncae. All subsequent authors followed this 1904 usage of the name speluncae. Large series of B. speluncae Henry van der Schalie collected in 1936 from the Peten is the first material of that species collected since Morelet visited the area. The material permits a redescription of that species, which warrants the recognition of B. dubia as a distinct species. Brachypodella speluncae (Pfeiffer) (fg. 5, F-H) Cglindrella costulata Morelet; 1852, Test. Noviss., II: 12. ( Type locality: Joe- bixinal Cave, near the capital of Peten; Guatemala). (Not Culindrella costulata C. B. Adams, 1849). -I: C!/lindrella speluncae Pfeiffer, 1852, Zeitschrift fur Malak.: 151. - Fischer and Crosse, 1872, Miss. Scient. au Mexico, Moll., I: 410; pl. I7, fig. 11. Brachypodella speluncae C Pfeiffer), Pilsbry, 1904, Man. Conch., Ser. II, 16: 69-71 (in part); pl. 6, figs. 17, 18. GUATEMALA·(DEPT. PETEN) knoll 1.2 mi. s. Flores (UMMZ 64540. 78); Cubixinal Cave, s. of Flores (UMMZ 64541. 15); 7-9 km. s.w. San Benito (UMMZ 64543. 1); 2 km. s. Puebla Nueva (UMMZ 64538. 62); knoll e. La Libertad (UMMZ 64588.51); w. shore Lago de Petenxil (UMMZ 64589. 168); San Andres (UMMZ 64542. 81). 1967 THOMPSON: SNAILS OF CAMPECHE 253 This species is known only from a small area in Peten. Rec6rds outside this area refer to B. dubia (Pilsbry). Shell dull, light beige; inside of aperture and peristome shiny white. Imperforate. Thin, nearly translucent. Elongate-turrete; widest at about the fourth or fifth from last whorl and tapering below. Spire very attenuate when complete. 21.2-28.6 whorls in adults with com- plete spires. Shell usually decollate at maturity; 13.0-14.6 whorls be- low apical plug. Whorls moderately convex; periphery above middle of whorl. Aperture extending forward and down on a long neck that is about U as long as diameter of shell. Neck with a strong basal ridge. Aperture subcircular, with a broad Raring peristome that is about 9 the width of the aperture. Peristome widest in baso-columellar region; 0.40-0.55 mm. wide along columellar margin. Aperture weakly angulate in lower and outer margins; 3 rounded embryonic whorls that are nearly uniform in size. Second embryonic whorl 0.5-0.6 mm. wide. Embryonic whorls sculptured with fine, regularly spaced axial threads that are about 0.05 mm. apart. Following whorls gradually increasing in size. Sculptured with numerous axial ribs that are nearly uniformly spaced over the surface of shell. 21-31 ribs on antipenulti- mate whorl. Ribs weakly sigmoid and slightly oblique; very thin and relatively high, about 8-4 times as high as wide. Ribs slightly thickened and raised near lower suture. Internal axis thin, rounded, weakly spiral. Length of complete shell, 14.7-16.2 mm.; length of shell below apical plug, 10.7-18.8 mm.; width of shell, 2.0-2.4 mm.; width of aper- ture including peristome, 1.7-2.2 mm. B. speluncae is conservative in variation. The sample gathered from beach drift along the west shore of Lago de Petenxil is unusual in that some stunted specimens have as few as 9.0 whorls. This species is distinguished by its large number of whorls below the apical plug, by its thin, high sigmoid ribs, by its elongate-turret shape, by its large number of ribs per whorl, and by its wide peris- tome. Available material from Peten and the Yucatan Peninsula shows no intergradation in these characters with B. dubia. XANTHONICHIDAE Averellia coactiliata (Deshayes) CAMPECHE: 5.1 mi. n.n.w. Dzibalch6n; 3.6 mi. s. Hopelch6n; 6,1 mi. s.w. Seyba- playa; 7.2 mi. s. Pixtdn; 10.2 mi. e. Escarcega; 19,2 mi, e. Silvituc. QUINTANA Roo: 4.0 mi, e. Xpujil, Campeche. 254 BULLETIN FLORIDA STATE MUSEUM Vol. 11 This species is usually found in mesic and rain forests, occasionally in dryer situations. Averellia suturalis (Pfeiffer) CAMPECHE: 5.1 mi. n.n.w. Dzibalch6n, 19.2 mi. e. Silvituc. QUINTANA Roo: 4.0 mi. e. Xpujil, Campeche; 2.8 mi. ske. Xiatil. This species has been found only in mesic and rain forests. POLYGYRIDAE Praticolella griseola (Pfeiffer) CAMPECHE: 8.1 mi. s.w. Champot6n; (17.2 mi. s. Champot6n. Branson and McCoy, 1965: 6);( 5-11 mi. e. Campeche. Branson and McCoy, 1963: 107). P64,gyra yucatanea (Morelet) CAMPECHE: (Isla de Carmen. Fischer and Crosse, 1872: 277). [Polt/gura oppilata (Morelet). Bequaert and Clench (1933: 532) restricted the type locality of this species to Campeche ("Littora Yucatanea"). No Campeche material is on record, and the species is known only from northern Veracruz and adjacent regions of Tamaulipas and San Luis Potosi.] Thysanophora caecoides (Tate) CAMPECHE: 8.1 mi. s.w. Champoton. QUINTANA Roo: 4.0 mi. e. Xpujil, Campeche; 7.l mi. n.n.w. Xiatil. YUCATAN: 1.0 mi. s. Puerto Telchac. Thysanophora plagioptycha (Shuttleworth) CAMPECHE: 7.1 mi. S.W. Campeche; 5.1 mi. n.n.w. Dzibalch6n; 19.2 mi. e. SiIvituc. YUCATAN: 0.8 mi. n.e. Becanch6n; 10.0 mi. n.e. Becanch6n. Th!/sanophora c. conspurcatelta (Morelet) CAMPECHE: 16.8 mi. s. Tenabo. 1967 THOMPSON: SNAILS OF CAMPECHE 255 Thysanophora impura (Pfeiffer) CAMPECHE: 0.9 mi. s:w Champ6t6n; ,11.4 mi. e. Caydl. YUCATAN: 0.8 mi. n.e. Becanch6n. All these species of Thysanophora are arboreal. Live specimens are difficult to find because of their minute size, but they can be col- lected in large numbers by shaking small trees and bushes over a sheet. SAGDIDAE Lacteoluna selenina (Gould) CAMPECHE: 7.2 mi. s. Pixtiln; 7.2 mi. s.w. Campeche; 5.1 mi. n.n.w, Dzibalch6n. LITERATURE CITED Baker, H. B. 1941. Outline of American Oleacininae and new species. Naut., 55: 51-61. 1948. The mainland genera of American Oleacininae. Proc. Acad. Nat. Sci. Phila.,95: 1-14. Bequaert, J. C. and W. J. Clench 1988. The peninsula of Yucatan. Medical, Biological, Meteorological, and Sociological Studies. Ch. XXVIII: The Non Marine Mollusks of Yucatan. Carnegie Inst. Wash. Publ., (481): 525-545. 1986. A second contribution to the Molluscan fauna of Yucatan.- Carnegie Inst. Wash. PubI., (457): 61-75. Branson, B. A. and C. J. McCoy, Jr. 1962. Streptostyki toltecorum and Streptostyla maslini, spp. nov. from Mexico. Naut., 76: 7-9. 1963. Gastropoda of the 1961 University of Colorado Museum expedition in Mexico. Naut., 76: 101-108. 1965. Gastropoda of the 1962 University of Colorado Museum expedition in Mexico. Univ. Colo. Stud. Biol., (13): 1-16. Fischer, P. and H. Crosse 1870-1900. Etude sur les mollusques terrestres et fluviatiles du Mexico et du Guatemala. Mission Scientifique au Mexico et dans l'Amerique Centrale., Pt. 7, Vols. 1, 2. Goodrich, C. and H. van der Schalie 1987. Mollusca of Peten and north Alta Verz Paz, Guatemala. Misc. Publ. Mus. Zool. Univ. Mich., (84): 1-50. 256 BULLETIN FLORIDA STATE MUSEUM Vol. 11 Harry, H. W. 1950. Studies on the non-marine Mollusca of Yucatan. Occ. Pap. Mus. Zool. Univ. Michigan, (524): 1-84. von Martens, E. 1890-1901. Land and freshwater Mollusca. Biologia Centrali-Americana. Zoologia, 9: i-xxviii, 1-706. Morelet, A. 1849. Testacea novissima. Paris. 1-89. Pilsbry, H. A. 1891. Land and freshwater mollusks collected in Yucatan and Mexico. Proc. Acad. Nat. Sci. Phila., 1891: 810-884. 1897. Manual of Conchology, 11: Bulimulidae. Philadelphia. 1-889. 1904. Manual of Conchology, 16: Urocoptidae. Philadelphia. 1-323. 1907. Manual of Conchology, 19: Oleacinidae. Philadelphia. 1-866. 1916. Manual of Conchology, 24: Pupilidae. Philadelphia., 1-324. 1919. Mollusca from Central America and Mexico. Proc. Acad. Nat. Sci. Phila., 1919: 212-228. Richards, H. G. 1937. Land and freshwater mollusks from the Island of Cozumel, Mexico, and their bearing on the geological history of the region. Proc. Amer. Philos. Soc., 77: 249-262. Solem, A. G. 1956. The helicoid cyclophorid mollusks of Mexico. Proc. Acad. Nat. Sci. Phila., 108: 41-59. 1961. A preliminary review of the pomatiasid land snails of Central America ( Mollusca, Prosobranchia) Archiv fur Molluskenkunde, 90: 191-213. Strebel, H. 1878. Beitrag zur Kenntnis der Fauna mixikanischer Land und Susswaser- Conchylien, III. Hamburg. 1-54. Wagner, P. L. 1964. Natural Vegetation of middle America. in, Handbook of Middle American Indians, Vol. 1: Natural Environment and Early Cultures. Univ. Texas Press. 216-263. West, R. C. 1964. Surface configuration and associate geology of middle America. in, Handbook of Middle American Indians, Vol. 1: Natural Environment and Early Cultures. Contributions to the BULLETIN OF THE FLORIDA STATE MUSEUM may be in any field of biology. Manuscripts dealing with natural history or systematic problems involving the southeastern United States or the Caribbean area are solicited especially. Manuscripts should be of medium length-50 to 200 pages. Examination for suitability is made by an Editorial Board. 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