Acta Herpetologica 12(2): 125-132, 2017 ISSN 1827-9635 (print) © Firenze University Press ISSN 1827-9643 (online) www.fupress.com/ah DOI: 10.13128/Acta_Herpetol-20740 Meristic and morphometric characters of Leptopelis natalensis tadpoles (Amphibia: Anura: Arthroleptidae) from Entumeni Forest reveal variation and inconsistencies with previous descriptions Susan Schweiger1, James Harvey2, Theresa S. Otremba1, Janina Weber1, Hendrik Müller1,* 1 Institut für Spezielle Zoologie und Evolutionsbiologie mit Phyletischem Museum, Friedrich Schiller Universität Jena, Erbertstrasse 1, 07743 Jena, Germany. *Corresponding author. E-mail: hendrik.mueller@uni-jena.de 2 41 Devonshire Avenue, Howick, 3290, South Africa Submitted on: 2017, 5th June; revised on: 2017, 31st August; accepted on: 2017, 3rd October Editor: Rocco Tiberti Abstract. The tadpole of Leptopelis natalensis is described based on a series of 32 specimens from Entumeni Forest, KwaZulu-Natal, South Africa. Previous descriptions are brief, lack morphometric data, or are based on specimens of imprecise origin. The tadpole resembles other Leptopelis tadpoles and is generally in agreement with existing accounts, although some differences exist. Some of these differences seem to fall within the range of natural variation. Others, such as the presence of a fifth anterior row of keratodonts, might be indicative of variation at the population level and should be considered in future taxonomic revisions. Leptopelis natalensis tadpoles seem to be most readily dis- tinguished by their more narrowly keratinized beaks from the geographically overlapping or adjacent L. mossambicus and L. xenodactylus. Keywords. South Africa, KwaZulu-Natal, Eastern Cape, taxonomy, buccal morphology, ontogenetic variation. INTRODUCTION The genus Leptopelis currently comprises 53 described species (Frost, 2017) of medium to large tree frogs that are distributed throughout most of Sub-Saha- ran Africa (Schiøtz, 1999). The most southerly distrib- uted species of the genus is L. natalensis, which is found in a variety of habitats along the eastern region of the South African provinces of KwaZulu-Natal and part of Eastern Cape (Schiøtz, 1999; Bishop, 2004; Venter and Conradie, 2015). Although some, mostly brief, descrip- tions and illustrations of L. natalensis tadpoles have been published (Wager, 1930, 1965; van Dijk, 1966; Lambiris, 1988; Channing, 2001; du Preez and Carruthers, 2009; Channing et al., 2012), Channing (2001) considered none of the South African Leptopelis tadpoles to have been adequately described. The various descriptions fur- thermore differ in a number of diagnostic characters, such as labial keratodont formula. These differences in the existing descriptions could be the result of variation or population-specific differences that might be signifi- cant in future taxonomic revisions (Penske et al., 2015). To differentiate between these options, it is important to provide detailed locality information, which is lacking in some works providing information on tadpole morphol- ogy of L. natalensis (e.g., du Preez and Carruthers, 2009). While detailed, or at least limited, locality data are pro- vided by Wager (1930, 1965, 1986), Pickersgill (2007) and Channing et al. (2012), these accounts provide mostly meristic data but few or no morphometric data that would help in assessing subtle differences that might exist between populations. We here provide a description and measurements of an ontogenetic series of tadpoles of L. natalensis based on a series collected at Entumeni Forest, 126 Susan Schweiger et alii KwaZulu-Natal, assess variability and ontogenetic chang- es, and highlight differences between these and previous descriptions. MATERIALS AND METHODS A total of 32 tadpoles were collected at Entumeni For- est, KwaZulu-Natal, South Africa on 3 December 2014. The tadpoles were collected in a small forest stream (28.888334°S, 31.365928°E). Some tadpoles were preserved on the day of col- lection, while others were raised on a diet of commercial aquar- ium fish food and sampled in regular intervals to obtain dif- ferent stages of development. Identification of the tadpoles was confirmed by raising some through metamorphosis. Specimens were euthanized in an aqueous solution of tricaine methanesul- fonate (MS222; Fluka), fixed in 4% neutral buffered formalin, and transferred to 70% ethanol. Voucher specimens have been deposited in the herpetological collection of the Museum für Naturkunde Berlin, Germany (ZMB85717). Staging followed Gosner (1960). Standard measurements and labial tooth row formula followed Altig and McDiarmid (1999) and description of buccopharyngeal morphology Was- sersug (1976). Drawings were prepared with the aid of a camera lucida attached to a Zeiss SV12 stereomicroscope. For inspec- tion of the buccopharyngeal morphology, one tadpole of stage 36 was dissected, postfixed with 1% osmium tetroxide, dehy- drated and critical point dried in an Emitech K850 critical point dryer, sputter coated with gold-palladium using an Emitech K500 and investigated using a Phillips XL30 ESEM scanning electron microscope with a digital image capture system. DESCRIPTION Tadpole. The description is based on 32 tadpoles from Gosner (1960) stages 25 to 42 (see Table 1 for measurements and detailed information). The tadpole is slender overall, with a moderately elongated, slightly dorsoventrally flattened body (wider than deep) and a relatively long tail with low dorsal and ventral fins. The widest point of the body is just behind the eyes (Fig. 1). No nares are visible until stage 34. From stage 35 to 37, the nares are indicated as light coloured spots, but do not seem to be open until stage 38. When fully formed, the nares are positioned dorsolaterally, about twice as far from the eye than the tip of the snout in lateral view. The eyes are positioned dorsally. A small anlage of the devel- oping eyelid is first visible at stage 40, anterior of the eye. The spiracle is sinistral, about as far from the snout as from the body-tail junction. The spiracular opening is an upright oval, slightly slanted forward; its largest diam- eter almost as large as the diameter of the eye lens. The spiracular tube is angled upwards at about 45°; the pos- terior end, including its inner wall, is free from the body. The tail is about 2.5 times as long as the body (see Table 1 for measurements) and very muscular. The myomeres are visible in the posterior half of the tail, but are other- wise indistinct or obscured by the dense pigmentation. The tailfins are very low, with the dorsal fin marginally deeper than the ventral fin. The dorsal fin has a low ori- gin on the base of the tail, just behind the tail-body junc- tion, and gradually rises towards the middle of the tail, where it reaches its maximum height. The ventral tailfin is very even, with the margin of the fin running more or less parallel to the ventral edge of the muscular tail. The overall deepest point of the tail is at about half its length. Tip of tail is pointed, with the muscular tail terminating some distance before the tail tip (Fig. 1B). The vent tube is attached to the right side of the ventral tailfin, with a very large opening forming a pointed arch. The coiled gut is well visible through the ventral body wall. Oral Disc. The oral disc is positioned subterminally and is not visible in dorsal view. The oral disc is light- ly emarginated and has a broad rostral gap. One row of globular marginal papillae is present anterolaterally and laterally; posteriorly, two rows of papillae are pre- sent. Papillae are largest anterolaterally and laterally, and smaller posteriorly. A few submarginal papillae are pre- sent laterally. Keratodont formula is 4(2-4)/3(1) in the majority of the examined specimens (see below for vari- ation). Moving inwards, supralabial keratodont rows are progressively smaller (Fig. 1A), infralabial rows are of nearly equal length, with P3 being slightly shorter than P1 and P2. Interruption of P1, if present, is very nar- row in some specimens (Fig. 1A) but more pronounced in others. Keratodonts are about equally sized in most rows, except in P3 where they get progressively smaller laterally. The individual keratodonts are spoon-shaped and have eight or nine cusps along their margins, with the apical cusps being larger than the more laterally positioned ones (see inset in Fig. 2A). The jaw sheaths are serrated but only narrowly keratinised (indicated by the dark pigmentation). By stage 42, the lower jaw sheath and all keratodonts are absent and the papillation is much reduced in extent. Buccopharyngeal Morphology. The prenarial area of the buccal roof (Fig. 2A) is somewhat elongated and con- tains a few scattered pustules. In addition, a pair of short ridges is present and somewhat slanted laterally. The ori- entation of the choana is oblique to the midline (about 45 degrees) and both choanae form a forward-pointing angle of approximately 90 degrees. The jagged narial valves pro- ject deep into the buccal cavity and obscure the choanal openings. Anterolateral of each choana is a broad, flap- like papilla with a pustulate edge. Three to four thick, broad-based papillae are present posterolaterally to each 127Tadpole of Leptopelis natalensis Table 1. Measurements of Leptopelis natalensis. All measurements in millimeters (arithmetic mean ± SD). * indicates a damaged tail in one of the specimens of the series, which was omitted from the calculations. Gosner Stage 25 (n=3) 31 (n=1) 34 (n=1) 35 (n=2) 36 (n=14) 37 (n=2) 38 (n=2) 39 (n=1) 40 (n=1) 41 (n=1) 42 (n=4) Total length 32.1 ± 2.3* 29.7 34.9 34.1 ± 1.2 36.5 ± 2.7* 35.3* 37.9 ± 0.8 41.7 39.1 37.2 36.2 ± 2.3 Body length 7.1 ± 0.6 8.2 9.5 9.2 ± 0.8 10.2 ± 0.8 10.7 ± 0.0 10.7 ± 0.8 11.8 11.2 11.0 10.9 ± 0.3 Body width 3.8 ± 0.2 4.0 4.9 4.5 ± 0.3 5.2 ± 0.6 5.9 ± 0.1 5.9 ± 0.1 6.0 6.1 5.5 4.3 ± 0.6 Body height 2.9 ± 0.1 3.6 4.2 3.4 ± 0.4 4.3 ± 0.4 4.8 ± 0.1 4.9 ± 0.1 5.3 4.4 5.0 4.2 ± 0.2 Tail length 16.7 ± 1.6* 21.2 25.2 24.9 ± 0.1 26.4 ± 2.3* 24.5* 27.1 ± 0.4 30.0 27.6 27.0 26.1 ± 1.8 Tail height 3.3 ± 0.3 3.6 4.2 4.1 ± 0.4 4.6 ± 0.3 4.4 ± 0.6 5.1 ± 0.4 5.0 4.9 5.0 4.1 ± 0.5 Tail muscle height 1.9 ± 0.3 2.3 3.0 2.8 ± 0.2 3.2 ± 0.4 3.2 ± 0.1 3.1 ± 0.1 3.5 3.0 2.9 2.8 ± 0.3 Width of oral disc 1.2 ± 0.2 1.4 1.6 1.6 ± 0.1 1.9 ± 0.2 1.9 ± 0.1 2.0 ± 0.1 2.4 2.2 2.0 1.6 ± 0.2 Interorbital distance 2.7 ± 0.3 3.3 3.9 3.5 ± 0.8 4.1 ± 0.3 4.4 ± 0.1 4.3 ± 0.1 4.6 4.3 4.7 4.7 ± 0.4 Internarial distance - - - - - - 1.9 ± 0.9 2.0 1.9 1.7 1.4 ± 0.2 Snout-naris distance - - - - - - 1.6 ± 0.1 1.6 1.7 1.6 1.2 ± 0.3 Snout-eye distance 2.5 ± 2.6 2.9 3.3 3.4 ± 0.1 3.3 ± 0.2 3.5 ± 0.2 3.4 ± 0.1 3.9 4.0 3.8 3.1 ± 0.1 Snout-spiracle distance 4.9 ± 0.5 5.4 6.1 6.3 ± 0.4 6.7 ± 0.4 27.1 ± 0.3 7.1 ± 0.2 8.1 7.4 7.2 - Naris-eye distance - - - - - - 1.9 ± 0.1 2.1 2.0 2.1 2.2 ± 0.1 Eye diameter 0.6 ± 0.1 0.8 1.1 1.0 ± 0.0 1.2 ± 0.1 1.2 ± 0.1 1.2 ± 0.1 1.5 1.5 1.5 1.4 ± 0.1 Fig. 1. Oral disc (A), lateral (B) and dorsal (C) view of a Gosner stage 36 tadpole of Leptopelis natalensis from Entumeni Forest, KwaZulu Natal, South Africa. Scale bar equals 0.5 mm in (A) and 5 mm in (B) and (C). 128 Susan Schweiger et alii Fig. 2. Scanning electron microscope images of the (A) buccal roof and (B) buccal floor of a Gosner stage 36 tadpole of Leptopelis natalen- sis. Inset in (A) shows a close-up of a keratodont. Scale bars in (A) and (B) equal 1 mm, and 5 µm in the inset. 129Tadpole of Leptopelis natalensis choana, and about six small pustules are present in the area between them. The median ridge separating post- narial arena and buccal roof arena is very prominent and forms an almost semi-circular flap. The buccal roof arena is fringed by eight pairs of medium to large papil- lae of similar sizes as in the buccal floor arena. An addi- tional three to four pairs of smaller papillae are present in second row towards the posterior part of the buccal roof arena. There is furthermore a group of three to four short lateral roof papillae at each side of the arena. Within the buccal roof arena and posterior to it are ca. 100 pustules. A well-defined glandular zone with numerous secretory pits is present; it is broader laterally and has a relatively narrow medial gap. The dorsal velum has a broad medial gap and number of smaller papillae and pustules along its edge and sides. Additional pustules are present posterior to the dorsal velum and within its median gap. In the buccal floor (Fig. 2B), a pair of large, flap- like infralabial papillae, with smaller pustules along their margins, is present immediately inside the oral cavity on each side. An additional large, flap-like infralabial papil- la is present medially just behind the lower jaw sheath. Four large lingual papillae are present on the tongue anlage. The area immediately behind the lingual papillae is marked by a transverse groove. To the left and right of this grove is a fairly large, bulbous structure. The buccal floor arena is fringed by nine to ten pairs of medium to large buccal floor papillae, all curved towards the buccal floor arena, except for the posteriormost pair of papillae, which point backwards (possibly an artefact of preserva- tion). Around 60 pustules cover the posterior two thirds Table 2. Ontogenetic variation in labial keratodont formula. Num- ber in brackets indicates number of specimens exhibiting the labial keratodont formula; asterisk (*) indicates asymmetry in the last (innermost) anterior keratodont row, with keratodonts present on one side only; keratodont data were only taken for 13 of the 14 investigated specimens of stage 36. Stage Labial keratodont formula 25 4(2-4)/3(1) [2]; 4(2-4*)/3 [1] 31 5(2-5)/3(1) [1] 34 5(2-5*)/3(1) [1] 35 4(2-4)/3(1) [2] 36 4(2-4)/3(1) [6]; 4(2-4)/3 [1]; 5(2-5*)/3(1) [1]; 5(2-5)/3(1) [5] 37 5(2-5)/3(1) [2] 38 4(2-4)/3(1) [2] 39 5(2-5)/3(1) [1] 40 5(2-5*)/3(1) [1] 41 5(2-5*)/3(1) [1] Table 3. Summary of published information on Leptopelis natalensis tadpoles. EC – Eastern Cape Province, KZN – KwaZulu-Natal Prov- ince, G – Gosner (1960) stage. Reference Locality Keratodont formula Oral disc characters Maximum length /tail length as multiple of body length this study Entumeni Forest (KZN) 4(2-4)/3(1) or 5(2-5)/3(1), rarely 4(2-4)/3 double row of marginal papillae posteriorly, single row of slightly larger papillae laterally; jaw sheaths delicate and narrowly keratinized; disc emarginated 42mm (G39)/2.5x Wager (1930) Port St. Johns (EC) 4(2-4)/3 double row of marginal papillae posteriorly, single row laterally; disc emarginated 51mm/2.5x Wager (1965) Port St. Johns (EC) 4(2-4)/3 double row of marginal papillae posteriorly, single row laterally; disc emarginated 49mm/2.75x Durban (KZN) 4(2-4)/3 35mm/2.5x Nkandla (KZN) 5(2-5)/3 50mm/2.3x Lambiris (1988) - 4(2-4)/3 double row of marginal papillae posteriorly, single row laterally 50mm (G38)/- Pickersgill (2007) Hillcrest (KZN) 4(2-4)/3, sometimes 4(2- 4)/3(1) double row of marginal papillae posteriorly, single row laterally; jaw sheaths narrowly keratinized; disc not emarginated 49mm (G37?)/2.5x du Preez and Carruthers (2009) - 4(2-4)/3, sometimes 4(2- 4)/3(1) double row of marginal papillae posteriorly, single row laterally; jaw sheaths delicate 50mm/2.6x (figured tadpole) Channing et al. (2012) KZN 4(2-4)/3 double row of marginal papillae posteriorly, single row of slightly larger papillae laterally; jaw sheaths delicate and keratinized along margins; disc emarginated 35mm/2.2x 130 Susan Schweiger et alii of the buccal floor arena, as well as the area immediately posterior to it. In addition, ca. 15 pustules are present anterolaterally of the buccal floor arena, just in front of the buccal pockets. The buccal pockets are simple, narrow but deep, curved slits, with no associated papillae or pus- tules. It is unclear whether the buccal pockets are perfo- rated to provide a bypass to the atrial chamber (Wasser- sug, 1976) or whether these end blind. The ventral velum is wide, with four marginal projections on each side, and a deep medial notch that exposes the glottis. The ventral velum contains secretory pits along its margin. Coloration in life. A nearly uniform dark olive, with a scatter of iridiophores across the entire dorsal and lat- eral sides of body and tail. Ventral side more sparsely pigmented anteriorly, but skin above the abdominal cav- ity completely unpigmented and translucent in younger stages but becoming somewhat more opaque in older specimens. Coloration in preservative. Dorsal body densely pig- mented and overall homogenously dark brown in col- our. Lateral line system very well visible as pigment-free spots in clearly defined lines along the body. Ventral body sparsely pigmented anteriorly but pigment-free above the abdominal cavity, with the coiled gut clearly visible. Pigmentation becomes somewhat less dense on tail and individual melanophores more easily discernible. Pigmentation on the dorsal tail-fin similar to the muscu- lar tail, but distalmost edge pigment-free. Ventral fin free of pigment and translucent, with only some scattered melanophores present along the basal edge and towards the posterior end. Variation. Overall, little variation is present within the examined material. Specimens differ slightly in the distribution of melanophores on the tail-fins, with some specimens having a ventral tailfin that is almost entirely free of pigmentation except for the very tip of the tail, whereas others show scattered pigment to a various extent within the posterior half of the fin. Pigmentation of the dorsal fin also slightly less or more dense in some specimens. The most variation is seen in the oral disc, in particular the number and arrangement of keratodont rows. Slightly more than half of the specimens (14 of 27; see Table 2) have four anterior rows of keratodonts, with the first always undivided, and the remainder divided. The rest of the specimens have an additional, innermost fifth keratodont row (A5). In all specimens, the last ante- rior row is usually rather short and in a number of speci- mens present on one side only (Table 2). The first posteri- or row is usually divided by a small gap of variable width, but undivided in two of the 27 specimens examined that have an oral apparatus. DISCUSSION Overall, the tadpole of L. natalensis resembles other Leptopelis tadpoles in general shape and appearance (see Channing et al., 2012, and Barej et al., 2015, for most recent and comprehensive treatments of the group). In South Africa, the range of L. natalensis is close to or overlaps with the ranges of L. xenodactylus and L. mos- sambicus (Channing, 2001; Minter et al., 2004). Based on the available information, the tadpole of L. mossam- bicus appears to be somewhat larger and proportion- ally shorter-tailed than that of L. natalensis, and overall darker in colouration, being more brown than olive (du Preez and Carruthers, 2009). Leptopelis mossambicus fur- ther appears to differ from L. natalensis by having slightly higher tailfins, a very broad rostral gap in the papilla- tion of the oral disc that is almost as broad as the disc itself, and somewhat more robust jaw sheaths that are keratinized for about half their width (du Preez and Car- ruthers, 2009; Channing et al., 2012). The tadpole of L. xenodactylus is very similar to L. natalensis and these species appear to be indistinguishable by overall shape and colouration alone. However, in contrast to L. natal- ensis, L. xenodactylus tadpoles do seem to have a more robustly keratinized jaw (Channing, 2008; du Preez and Carruthers, 2009; Channing et al., 2012), which should help facilitate a correct identification. In addition there are differences in papillation, with more submarginal papillae being present in L. xenodactyloides and the pos- terior papillae differing in size (inner row of shorter, more globular papillae and outer row of relatively long papillae; Channing 2008). The two species have so far not been found in sympatry, although they occur in close proximity to each other in central KwaZulu-Natal. A number of descriptions of the tadpole of L. natal- ensis have been provided before (summarized in Table 3), but most of them are brief, lack measurements, or do not provide precise locality information. All previ- ous accounts and our observations agree on the overall shape and colouration of the tadpoles, but some differ- ences especially in total length, oral disc morphology, and keratodont formula exist. While most accounts provide a maximum length of around 50 mm, Wager (1965) and Channing et al. (2012) reported 35 mm as total length, at least for some populations, but did not indicate what stage the examined specimens were at. Furthermore, there is some variation regarding the length of the tail, but all of this seems to be within the limit of normal vari- ation, given that maximum length is largely dependent on condition. While most previous investigators reported or figured a slightly emarginated oral disc, which matches our own observations, Pickersgill (2007) illustrated a disc 131Tadpole of Leptopelis natalensis that is not emarginated. Assuming all observations to be correct, this would indicate a more substantial differ- ence between that population and others. Both van Dijk (1966) and du Preez and Carruthers (2009) reported the presence of an elygium in the eye of L. natalensis tad- poles, although van Dijk (1966) indicated that an ocular elygium might not generally be present and is not easily detected. In our specimens, an ocular elygium is not pre- sent, but dorsally the pigmented skin seems to somewhat extend onto the eyeball, which may represent an epider- mal elygium (see Kruger et al., 2013). Most previous descriptions gave the keratodont for- mula of L. natalensis tadpoles as 4(2-4)/3, indicating an undivided P1 (Wager, 1930, 1986; Lambiris, 1988; Pick- ersgill, 2007; du Preez and Carruthers, 2009; Channing et al., 2012), but Pickersgill (2007) and du Preez and Carruthers (2009) also stated that P1 can sometimes be divided. In our series, only two specimens had an undi- vided P1, the rest all had a divided P1 although the gap was very slight in some specimens. While this may be an indication of interpopulational variation, it seems possi- ble that previous reports might have simply overlooked a narrow gap in P1. Similar variations in the presence of a divided vs. undivided P1 have been reported by Penske et al. (2015) for Leptopelis cf. grandiceps. Furthermore, only slightly more than half of the specimens (14, see Table 2) of our ontogenetic series of L. natalensis tadpoles had four anterior rows of keratodonts. Almost as many (13 specimens) had an additional, divided A5 and a result- ing keratodont formula of 5(2-5)/3(1). Although also pre- sent in some younger specimens, the presence of an A5 seemed to be more pronounced in older tadpoles (Table 2). Variation in the number of keratodont rows has been reported for a number of species, including L. calcaratus, L. gramineus, L. vannutelli and L. yaldeni (see Channing et al., 2012). An ontogenetic increase has further been reported for L. aubryoides (Barej et al., 2015), L. calcara- tus (Lamotte and Perret, 1961) and L. viridis (Rödel 2000), and specimens with an additional A5 have been reported for L. modestus, L. spiritusnoctis and L. rufus (Barej et al., 2015). In many anuran tadpoles, anterior keratodont rows are added during ontogeny and the presence of an A5 in some Leptopelis might be related to overall tadpole size. It is therefore possible that previous investigations did not examine specimens of a sufficient age for an A5 to be expressed. At the same time, the maximum length of 50 mm reported by several authors for L. natalen- sis (e.g., Wager, 1930; Lambiris, 1988; see Table 2 for full list), which substantially exceeds the 42 mm of the largest specimen in our sample, would argue against this. Only Wager (1965) reported tadpoles with an A5 from Nkandla Forest, KwaZulu-Natal. Entumeni Forest, the origin of the specimens examined here and only other reported popu- lation of L. natalensis tadpoles with a fifth anterior row of keratodonts, is less than 30 km away from Nkandla Forest. Given the current state of knowledge, these two popula- tions seem diagnosably different from other L. natalensis populations at the level of tadpole morphology. Future studies of phylogeography of L. natalensis should include these populations and investigate their degree of differen- tiation compared to others. ACKNOWLEDGEMENTS We would like to thank Ezemvelo KZN for issuing the necessary permits (OP4976/2013, OP635/2014) to undertake our research and in particular Adrian Arm- strong and Sharon Louw for their generous advice and help facilitating our work. For help in the field we are grateful to Lars Möckel and Katrin Friedemann. Fund- ing was provided through a German Science Foundation (DFG) grant to HM (MU2914/2-1). REFERENCES Altig, R., Mc Diarmid, R.W. (1999): Body plan – develop- ment and morphology. In: Tadpoles – the biology of anuran larvae, pp. 24-51. Mc Diarmid, R.W., Altig, R., Eds, Chicago University Press, Chicago. Barej, M.F., Pfalzgraff, T., Hirschfeld, M., Liedtke, H.C., Gonwouo, N.L., Penner, J., Dahmen, M., Doherty- Bone, T., Schmitz, A., Rödel, M.O. (2015): The tad- poles of eight West and Central African Leptopelis species (Amphibia: Anura: Arthroleptidae). Amphib. Rept. Cons. 9: 56-84. Bishop, P.J. (2004): Leptopelis natalensis (Smith, 1849). In: Atlas and red data book of the frogs of South Africa, Lesotho and Swasiland, pp. 160-162. Minter, L.R., Burger, M., Harrison, J.A., Braack, H.H., Bishop, P.J., Kloepfer, D., Eds, Smithsonian Institution, Washing- ton, D.C. Channing, A. (2008): The mud dwelling tadpole of the long-toed tree frog, Leptopelis xenodactylus (Arthro- leptidae). Herp. Rev. 39: 288-290. Channing, A. (2001): Amphibians of Central and South- ern Africa. Comstock Publishing Associates, Cornell University Press, Ithaca. Channing, A., Rödel, M.O., Channing, J. (2012): Tadpoles of Africa. Edition Chimaira, Frankfurt-am-Main. du Preez, L., Carruthers, V. (2009): A complete guide to the frogs of Southern Africa. Struik Nature, Cape Town. 132 Susan Schweiger et alii Frost, D.R. (2017): Amphibian Species of the World: an Online Reference. Version 6.0 (accessed 23 May 2017). Electronic Database accessible at http:// research.amnh.org/herpetology/amphibia/index.html. American Museum of Natural History, New York. Gosner, K.L. (1960): A simplified table for staging anuran embryos and larvae with notes on identification. Her- petologica 16: 183-190. Kruger, D.J.D., Weldon, C., Minter, L.R., du Preez, L.H. (2013): Morphology of the elygium and developing umbraculum in the eye of Amietia vertebralis tad- poles. J. Morphol. 274: 551-556. Lambiris, A.J.L. (1988): A review of the amphibians of Natal. Lammergeyer 39: 1-212. Lamotte, M., Perret, J.L. (1961): Contribution à l’étude des batraciens de l’Ouest africain XIII. Les formes lar- vaires de quelques espèces de Leptopelis: L. aubryi, L. viridis, L. anchietae, L. ocellatus et L. calcaratus. Bul- letin de l’Institut Fondamental d’Afrique Noire, Serie A 3: 855-885. Minter, L.R., Burger, M., Harrison, J.A., Braack, H.H., Bishop, P.J., Kloepfer, D., Eds. (2004): Atlas and Red Data Book of the Frogs of South Africa, Lesotho and Swasiland. SI/MAB Series 9. Smithsonian Institution, Washington, D.C. Penske, S., Gvoždík, V., Menegon, M., Loader, S.P., Mül- ler, H. (2015): Description of the tadpole of Leptope- lis cf. grandiceps (Amphibia: Anura: Arthroleptidae) from the Uluguru Mountains, Tanzania. Herpetol. J. 25: 61-64. Pickersgill, M. (2007): Frog search: results of expeditions to Southern and Eastern Africa. Edition Chimaira, Frankfurt-am-Main. Rödel, M.O. (2000): Herpetofauna of West Africa. Vol- ume I: Amphibians of the West African savanna. Edi- tion Chimaira, Frankfurt-am-Main. Schiøtz, A. (1999): Treefrogs of Africa. Edition Chimaira, Frankfurt-am-Main. Van Dijk, D.E. (1966): Systematic and field keys to the families, genera and described species of South Afri- can anuran tadpoles. Ann. Natal. Mus. 18: 231-286. Venter, A.J., Conradie, W. (2015): A checklist of the rep- tiles and amphibians found in the protected areas along the South African Wild Coast, with notes on conservation implications. Koedoe 57: 1-25 Wager, V.A. (1930): The breeding habits and life-histories of two rare South African Amphibia. I. Hylambates natalensis A. Smith. II. Natalobatrachus bonebergi Hewitt and Methuen (plates V-X). Trans. Roy. Soc. S. Afr. 19: 79-91. Wager, V.A. (1965): The frogs of South Africa. Purnell and Sons, Cape Town. Wager, V.A. (1986): Frogs of South Africa: Their Fascinat- ing Life Stories. Delta Books, Craighall. Wassersug, R.J. (1976): Oral morphology of anuran lar- vae: terminology and general description. Occ. Pub. Mus. Nat. Hist. Univ. Kansas 48: 1-23. Acta Herpetologica Vol. 12, n. 2 - December 2017 Firenze University Press Meristic and morphometric characters of Leptopelis natalensis tadpoles (Amphibia: Anura: Arthroleptidae) from Entumeni Forest reveal variation and inconsistencies with previous descriptions Susan Schweiger1, James Harvey2, Theresa S. Otremba1, Janina Weber1, Hendrik Müller1,* Brown anole (Anolis sagrei) adhesive forces remain unaffected by partial claw clipping Austin M. Garner*, Stephanie M. Lopez, Peter H. Niewiarowski Species and sex comparisons of karyotype and genome size in two Kurixalus tree frogs (Anura, Rhacophoridae) Shun-Ping Chang1,2, Gwo-Chin Ma2,3,4, Ming Chen2,5,6,7,8,*, Sheng-Hai Wu1,* Non-native turtles in a peri-urban park in northern Milan (Lombardy, Italy): species diversity and population structure Claudio Foglini1, Roberta Salvi2,* Species composition and richness of anurans in Cerrado urban forests from central Brazil Cláudia Márcia Marily Ferreira1,*, Augusto Cesar de Aquino Ribas2, Franco Leandro de Souza3 The life-history traits in a breeding population of Darevskia valentini from Turkey Muammer Kurnaz, Alı İhsan Eroğlu, Ufuk Bülbül*, Halıme Koç, Bılal Kutrup Influence of desiccation threat on the metamorphic traits of the Asian common toad, Duttaphrynus melanostictus (Anura) Santosh Mogali*, Srinivas Saidapur, Bhagyashri Shanbhag Predation of common wall lizards: experiences from a study using scentless plasticine lizards Jenő J. Purger*, Zsófia Lanszki, Dávid Szép, Renáta Bocz Reproductive timing and fecundity in the Neotropical lizard Enyalius perditus (Squamata: Leiosauridae) Serena Najara Migliore1,2,*, Henrique Bartolomeu Braz2,3, André Felipe Barreto-Lima4, Selma Maria Almeida-Santos1,2 Observations on the intraspecific variation in tadpole morphology in natural ponds Eudald Pujol-Buxó1,2,*, Albert Montori1, Roser Campeny3 and Gustavo A. Llorente1,2 Reliable proxies for glandular secretion production in lacertid lizards Simon Baeckens Diet of juveniles of the venomous frog Aparasphenodon brunoi (Amphibia: Hylidae) in southeastern Brazil Rogério L. Teixeira1, Ricardo Lourenço-de-Moraes2, Débora C. Medeiros3, Charles Duca3, Rogério C. Britto4, Luiz C. P. Bissoli5, Rodrigo B. Ferreira3,* Who are you? The genetic identity of some insular populations of Hierophis viridiflavus s.l. from the Tyrrhenian Sea Ignazio Avella, Riccardo Castiglia, Gabriele Senczuk*