IBN AL- HAITHAM J. FOR PURE & APPL. SCI VOL.23 (1) 2010 Description of A new Species Belong to the Genus Hemicypris Sars , 1903 (Crustacea/Ostracoda ) from Iraq H. Z. M. AL-Da’amy Department of Biology ,College of Education,University of Karbala’a Taxonomy of crustacean (Ostracoda) Abstract The present study introduces description of a new species of class Ostracoda genus Hemicypris Sars, 1903. External morphological characters particularly shape, size and structure of left and right valves of carapace and body appendages were discussed and illustrated. Locality and date of collection were given. Introduction Members of the class Ostracoda are small tiny organisms , the majority are freshwater species in which the length of adults is ranging from 0.5-2.5 mm [1,9] . Usually, they are found in every aquatic habitates including marine and non-marine , while others appear as semi – terrestrial , but no species known to be terrestrial [10] . It was found that the occurrence of Ostracods is related to water nature, air temperature and even water chemistry [4,6,7,8] . The taxonomy of freshwater Ostracods is based mainly on shape and size of left and right carapace [12] . Species of the genus Hemicypris Sars 1903 are characterized by the followings: carapace relatively stout laterally, left valve of carapace is crenulated anteriorly and posteriorly , right valve larger and overlapping the left one [10] . Material and Methods Specimens were collected by using zooplankton net during May , 2004, from different regions of Karbala'a governorate. They were preserved in vials contain 70% alcohol with few drops of glycerol . For dissection , both right and left valves were removed carefully by using fine dissection needles and the appendages . The dissected body parts were isolated from each other and mounted on microscopic slide with a drop of glycerine . They were drawn by using compound microscope with ocular micrometer. Keys for identification were used according to [3,5,10,11] . Results and Dissection Hemicypris irarkensis sp. nov. This species was firstly described to the science . Its name was derived from the name of our country . Carapace:Fig.1 Oval, total length 0.65mm; light brown and hyaline. Outer surface is smooth and covered with regularly distributed small hairs; its posterior end is rounded, much broader in the middle and would become narrower gradually toward the anterior end which is distinctly pointed. Right valve larger than left valve and overlapping the latter ventrally and anteriorly, the free margins of the two valves overlap to realize a tight closure . Eyes fused. IBN AL- HAITHAM J. FOR PURE & APPL. SCI VOL.23 (1) 2010 Right Valve:Fig.2 The right valve is larger and broader than the left one. Approximately oval approximately, outer surface smooth and hairy. Posterior margin narrowly rounded, Anterior margin is broadly rounded with hair on two long margins. Adductor muscles scar five differently arrangements. Left val ve:Fig.3 Approximately oval, outer surface smooth and hairy. Anterior margin is rounded mare than the posterior end with small pustules and hair. Five adductor muscles scar variable arrangements. First Antenna:Fig.4 Eight segmented; first (Basal) segment polygonal is bearing one long setae on its inner margin, second segment is the larger bearing two long setae on both inner and outer margins, third segments to eighth are graduating in size toward the smallest terminal (eight) segment which bears long terminal setae . There are ten long plumose natatory setae attached to the segments five to eight. Second Antenna:Fig.5 Five segments , terminal segment subdivided . First segment (Basal) is elongated and enlarged hummer –shaped; Second segment is enlarged with line shaped letter T ,bearing one long setae attached to the lower narrow margin. Endopod composed two segments, the first bear two short sensory setae and long other setae, the end of the segment which is attached to the second segment bears(5+1) ntatory setae well developed distinctly extending beyond the base of the terminal claws. Terminal segment subdivided, last bearing 5 terminal unequal claws and two terminal equal setae, at the lower(inner)margin attached with three setae. Exopod; reduced to small lobe bearing one very long seta and other small. Mandible:Fig.6 Basal segment elongated, much broader in the middle and narrowing gradually toward the apex which bears two identical setae, its base would protrude to form short broad process bears five sharp identical teeth and one terminal short seta . Palp consists of four segments, the first elongated and bearing single seta on the outer margin and vibratory plat which is consist of four long identical plumose filaments and one short plumose filament and all are attached to the basal segment of the mandibular palp, second segment of the mandibular palp is a small triangular with three long identical setae, third segment elongated, its outer margin with single short setae in addition to four long identical seta , there are two groups of setae consist of three plumose setae, setal group1 is attached to the inner margin of the first mandibular palp segment and setal group2 is attached to the inner margin of the third mandibular palp segment, fourth segment is very small square like and its apex bears three identical setae. Maxilla:Fig.7 Two segmented, the vibratory plate elongated and curved, its apex bears 12 p lumose setae four of them are long identical while the others eight are shorter, the base of the vibratory plate bears five equal setae, the basal segment short and swollen, its outer margin is much curved and bears two setae ending basally with three mastigatory processes which contain short setae arranged 3-3-5 respectively, the maxillary palp narrow and elongate ending with six setae, with three long setae on the inner margin. First Thoracopod:Fig.8 Triangular in shape ,the mastigatory process is slightly elongated ending with eight setae, the two on both sides are longer than the others which are equal in length, its outer margin bears one long setae, the mastigatory process jointed palp-like endopode ending with three setae, two long setae and one short and vibratory plate bear five slightly equal plumose setae. IBN AL- HAITHAM J. FOR PURE & APPL. SCI VOL.23 (1) 2010 Second Thoracopod: Fig.9 Five segmented , basal segment approximately square ,second segment bears in apex a single long seta and the inner margin contains few irregularly distributed small hairs, third and fourth segments bear a single long setae ,fifth segment is the smallest one triangular in shape and bears a well developed apical claw and two short setae on its sides. Third Thoracopod:Fig.10 Three segmented. basal segment elongated and narrow forming right angle with the other two segments, there are two reversed long setae at the junction between the basal(first) and second segments, the inner margin of the basal segment bears single plumose seta . Second segment is slightly winding its apex which bears long single seta, third segment more winding its apex which bears long lateral seta and other small swollen one . Uropod:Fig.11 Consists of T-shaped apical rod representing the apical half of the whole uropod . The other basal half appears as an elongated plate much narrow in the middle , its free end bears four unidentical claws. Comparision notes : The new species is closely related to the species Hemicypris posterotruncata Sars,1903 ,but differ by the following notes: 1-Posterior margin narrowly rounded. 2-Surface smooth and hairy . 3-Adductor muscle scars five differently arrangements. 4-Second antenna,A2-endopod terminal segment is subdivided Materials Examined *1 Female Holotype *1 Female Allotype *4 Females Paratype *Karbala’a _Iraq Coll ,May.2004.(Leg.Hanan Zwair) Acknowledgments I would like to introduce my appreciation to Dr. Wajeeh Al- Jumaily / University of Markab / Libya and Dr. Richard M. forester University of Denver United States , for their favor in identification of species and to certify the new species . References 1-Bowman,T. E.& Abele, LG.(1982).Classification of the recent crustacean In the biology of crustacea,Vol.1.Ed.D.E.Bliss,Academic Press London. 2- Bate, R. H. (1970) . Anew species of Hemicypris(Ostracoda) from ancient Beach Sediments of Lake Rudolf ,Kenya .palaeontology ,13 (2): 289-296. 3- Bronshtein, Z. S. (1947). Fresh water Ostracoda. Translat by Indira Nayar, Oxonian Press Pvt. Ltd., New Delhi: 470pp. 4-Delorme, L. D. and Zoltai, S. C. (1984). Distribution of an arctic Ostracoda fauna in space and time, Quaternary Research ,21(1):65-73. 5-Edmondson, W. T. (1959). Freshwater Biology.2nd. ed John Wiley&Sons, Inc. Newyork: 124 pp. 6-Forester , R . M . (1991) . Ostracode assemblages from in The western United States ; IBN AL- HAITHAM J. FOR PURE & APPL. SCI VOL.23 (1) 2010 Implications for paleohydrology . Mem . ent . soc . can , 155 : 181 - 201. 7-Forester, R . M . (1986) . Determination of the dissolved anion composition of anceint lakes from fossil Ostracodes . Geology .14 :746 - 798 . 8-Forester , R . M . (1983) . Relationship of two Lacustrine Ostracode species to solute composition & salinity : Implications for paleohydrochemistry , Geology , 11 : 435 _ 438 . 9-Henderson, P. A. (2002). Freshwater Ostracodes. Pisces Conser- vation Ltd: 258pp. 10-Meisch, C. (2000), Freshwater Ostracoda of Western & Central Europe. Spektrum Akademisher Verlog GmbH. Heidelberg, Berlin: 513pp. 11-Pennak, R. W. (1978). Fresh Water invertebrates of the United States. 2nd. ed. John Wiley & Sons, Inc. 2nd.ed.,803pp. 12-Victor, R. (2004). Crustacea: Ostracoda. In: yule, C. M & sen, Y.H. (Eds). Fresh water Invertebrates of the Malaysian Region. Academy of sciences M alaysion: 225 – 252. Table I Sympols English Term A1 A2 AM AMS AC AS BS Ca Cl DE DM E EXP ENP FI H L LV Md MP MX 1st Antenna 2nd Antenna Anterior Margin Addactor Muscle Scars Apical Claw Anterior Setae Basel Segment Carapace Claws Distal End Dorsal Margin Eye Exopod Endopod Filaments Hairs Loop Left Valve Mandible Masticatory Process Maxilla 3 rd MP NS Pa PM PS Pu RV SG1 SG2 Sc SS T1 T2 T3 Te TS UA U UR VP VM Therd Masticatory Process Natatory Setae Palp Posterior Margin Posterior Setae Pustuls Right Valve Setal Group 1 Setal Group 2 Scale Sensory Setae 1st Thoracopod 2nd Thoracopod 3rd Thoracopod Teeth Terminal Segment Uropodal Attachment Uropod Uropodal Ramuse Vibratoru Plate Ventral Margin E H LV RV 0.1mm Fig.(1): Surface view of carapace(Female) IBN AL- HAITHAM J. FOR PURE & APPL. SCI VOL.23 (1) 2010 H AMS Fig.(2): Lateral view of Right valve(Female) H AMS PU Fig.(3): Lateral view of left valve(Female) Species: Hemicypris irakensis sp.nov NS TS BS 0.5mm Fig.(4): First Antenna IBN AL- HAITHAM J. FOR PURE & APPL. SCI VOL.23 (1) 2010 ExP EnP SS TS BS BS CL Fig.(5) Second Antenna ( Species:Hemicypris irakensis sp.nov) BS P VP Pa SG1 SG2 Te 0.5mm Fig.(6): Mandible IBN AL- HAITHAM J. FOR PURE & APPL. SCI VOL.23 (1) 2010 VP BS Pa 3 rd MP Fig.(7): Maxilla Species:Hemicypris irakensis sp.nov VP BS Pa MP DS CL Fig.8 First Thoracopod Fig.(9): S econd Thoracopod 0.5mm DE AU TS PeS UR PS BS AS AC Fig.(10): Third Thoracopod Fig.(11): Uropod Species: Hemicypris irakensis sp.nov 2010) 1( 23مجلة ابن الھیثم للعلوم الصرفة والتطبیقیة المجلد Hemicypris Sars , 1903وصف نوع جدید یعود للجنس )Crustacea / Ostracoda (من العراق یر مخلف الدعميحنان زو جامعة كربالء، كلیة التربیة الخالصة تم . Hemicypris Sars,1903 یعود للجنس صنف الدرعیات تقدم الدراسة الحالیة وصفا لنوع جدید من القشریات .لواحق الجسم وباقيدرع لل واألیسر األیمنكیب المصراعین االمظهر الخارجي وخاصة شكل وحجم وتر دراسة صفات