J. Helminthol. Soc. Wash. 61(2), 1994, pp. 205-207 Drepanidotaenia teshekpukensis sp. n. (Cestoda: Hymenolepididae) from Black Brant, Branta bernicla nigricans, from the Teshekpuk Lake area of Alaska NORMAN O. DRONEN, SANDRA L. MARIN, AND ERIC J. TAYLOR Laboratory of Parasitology, Department of Wildlife and Fisheries Sciences, College of Agriculture and Life Sciences, Texas A&M University, College Station, Texas 77843 ABSTRACT: Specimens of Drepanidotaenia teshekpukensis sp. n. (Eucestoda: Hymenolepididae) were recovered from 68 black brant, Branta bernicla nigricans at Teshekpuk Lake, Alaska. Of the species of Drepanidotaenia with 10 rostellar hooks D. teshekpukensis sp. n. is most similar to D. barrowensis and D. bilateralis, which also occur in black brant. It differs from these 2 species in shape and size of rostellar hooks, position of the reproductive systems relative to the lateral excretory canals, and shape and size of the cirrus spines. The new species can be distinguished from all other species of the genus in having the centers of the ovary and vitellarium immediately poral of the center of the most antiporal testis. KEY WORDS: Drepanidotaenia teshekpukensis sp. n., Cestoda, Hymenolepididae, Branta bernicla, Alaska. Black brant, Branta bernicla nigricans Lin- Drepanidotaenia teshekpukensis sp. n. naeus, 1758 are commonly found along the (Figs. 1-6) northern Pacific coastlines of Asia and North DESCRIPTION (based on 20 specimens): With America. Eleven genera of tapeworms, including the characteristics of the genus. Strobila cras- 2 species of the genus Drepanidotaenia Railliet, pedote, total length of worms 16 mm (6-19), 1892, D. barrowensis (Schiller, 1952) Yamaguti, composed of 70-200 proglottids. Scolex 180 1959, and D. lanceolata (Block, 1782) Railliet, (140-220) long by 140 (105-200) wide. Suckers 1892 have been reported previously from this well developed, 70 (45-95) in diameter. Rostel- subspecies of brant in North America (Neraasen lum 65 (45-85) long with 10 hooks, arranged in and Holmes, 1975). A third species, D. bilateralis a circle, each 33 (29-35) long with blade 7 (4-8) (Linstow, 1905) Railliet, 1892 has been found in long, rostellar sac 109 (96-122) long by 49 (46- B. bernicla in Russia (Linstow, 1905; Spasskaya, 52) wide. Immature proglottids wider than long, 1966). The purpose of this study was to provide mature proglottids 150 (100-280) long by 900 additional information on the cestode fauna of (400-1,500) wide. Genital atria unilateral open- black brant. ing in the anterior fourth of proglottids. Three testes 86 (62-114) long by 88 (70-110) wide ar- Materials and Methods ranged in a straight line. Cirrus sac 360 (285- 500) long by 82 (45-115) wide. Cirrus 230 (145- Cestodes removed from intestines of 68 black brant 300) long, armed with symmetrical, similarly collected by netting and shooting from the Teshekpuk Lake area of Alaska from June through August from shaped spines, largest situated near the base and 1987 to 1989 were fixed without coverslip pressure in middle of cirrus, 23 (18-27) long, and smallest 10% formalin, stained in Semichon's carmine and at the tip, 5 (4-8) long. External seminal vesicle mounted in Kleermount or Canada balsam. Some 150 (72-235) long by 88 (27-140) wide. Ovary specimens were sectioned by conventional paraffin technique. Measurements were from whole mounts of antiporal, deeply lobed 90 (57-140) long by 130 adults and are given in /un, with the mean followed by (70-215) wide with its center situated ventrally, the range in parentheses, unless otherwise stated. Type immediately poral of the center of the most an- materials of D. barrowensis (no. 37341, USNM Hel- tiporal testis. Vitellarium lobed, situated directly minthological Collection) were examined. No speci- under the ovary, 47 (27-70) wide. Genital ducts mens of D. bilateralis were available for comparison. passing between ventral and dorsal excretory ducts, excretory ducts outside reproductive or- Results gans, ventral canals 33 (30-41) wide, dorsal ex- All black brant examined were infected with cretory canals 11 (10-13) wide. Vagina posterior an undescribed species of hymenolepidid cestode and ventral to cirrus sac. Seminal receptacle 67 of the genus Drepanidotaenia. (56-78) wide. Gravid proglottids wider than long, 205 Copyright © 2011, The Helminthological Society of Washington 0.07mm Figures 1-6. Drepanidotaenia teshekpukensis sp. n. from Branta bernicla nigricans. 1. Scolex. 2. Hook from rostellum. 3. Cirrus spine. 4. Enlarged view of genital atrium and seminal vesicle region showing the genital atrium (G), vagina (V), internal seminal vesicle (I), and external seminal vesicle (E). 5. Mature proglottid showing the internal seminal vesicle (I), external seminal vesicle (E), testis (T), seminal receptacle (S), vitellarium (Y), and ovary (O). 6. Gravid proglottid showing uterus. Copyright © 2011, The Helminthological Society of Washington DRONEN ET AL.-D. TESHEKPUKENSIS SP. N. 207 150 (90-300) long by 1,300 (730-1,900) wide. (Spasskaya, 1966); its external seminal receptacle Gravid uterus a transverse sac. Eggs ovoid, 28 is more spherical; its ovary is smaller, 130 (70- (27-30) long by 34 (35-38) wide, oncospheres 19 215) wide as compared to 330-440 (Spasskaya, (17-25) long by 23 (22-24) wide. 1966) and does not extend laterally past the ex- HOST: Branta bernicla nigricans. cretory canals; it has a smaller vitellarium, 47 SITE OF INFECTION: Small intestine. (27-70) wide, as compared to 72 wide (Schiller, LOCALITY: Teshekpuk Lake, Alaska (70°49'N, 1952) and 111-140 (Spasskaya, 1966); and its 153°15'W). uterus is a uniform transverse sac lacking the HOLOTYPE: USNM Helm. Coll. No. 82531. antiporal expansion described by Schiller (1952). PARATYPES: USNM Helm. Coll. No. 82533; The new species differs from D. bilateralis in Texas A&M Cooperative Wildlife Coll. No. 84- that it has a shorter total length, 16 mm, as com- 89AL, Department of Wildlife and Fisheries Sci- pared to 68 mm (Linstow, 1905; Spasskaya, ences, Texas A&M University and The Univer- 1966); its scolex is smaller, 180 long, as com- sity of Nebraska State Museum No. 35446, The pared to 220 long (Linstow, 1905; Spasskaya, Harold W. Manter Laboratory, University of 1966); its rostellar hooks are shaped differently, Nebraska. having a proportionally smaller blade that is ap- ETYMOLOGY: The species name refers to the proximately 20% of the total length of the hook, largest lake in the area where specimens were as compared to approximately 38% (Spasskaya, collected. 1966); its ovary is smaller, approximately V7 of proglottid width, as compared to lh of the pro- Discussion glottid width (Spasskaya, 1966); its excretory ca- nals are outside of the region occupied by the Of the species of Drepanidotaenia with 10 ros- reproductive organs, rather than being more me- tellar hooks, D. teshekpukensis sp. n. resembles dially situated (Spasskaya, 1966) and its cirrus both D. barrowensis and D. bilateralis, which sac and vagina pass between the ventral and dor- have been reported previously from black brant sal excretory ducts, rather than their being po- (Neraasen and Holmes, 1975; Spasskaya, 1966). sitioned ventral of the cirrus sac (Spasskaya, In both D. barrowensis and D. bilateralis the ova- 1966). ry can be substantially overlapped by the anti- poral testis, however, in both of these species the center of the ovary is always situated antiporal Acknowledgements of the most antiporal testis (Schiller, 1952; Spas- We greatly appreciate the reviews of this skaya, 1966). The new species can be distin- manuscript by John Holmes, Milton Weller, and guished from all described species of Drepani- Charles Blend, and the assistance of Louise Ru- dotaenia because the center of its ovary is bec in translating Russian literature. We are also consistently situated immediately poral of the indebted to Dr. J. R. Lichtenfels for the loan of center of the most antiporal testis. specimens of D. barrowensis from the U.S. Na- The new species differs from D. barrowensis tional Parasite Collection. in that it has a shorter total length, 16 mm, as compared to 70 mm reported by Schiller (1952) Literature Cited and 90 mm reported by Spasskaya (1966); its Linstow, O. F. B., von. 1905. Helminthen der rus- scolex is larger, 180 long by 140 wide, as com- sischen Polarexpidition 1900-1903. Memoirs of pared to 72 long by 96 wide (Schiller, 1952) and the Imperial Academy of Sciences, Saint Peters- 105-115 wide (Spasskaya, 1966); its rostellar burg 18:1-17. hooks are longer, 33 (29-35) long, as compared Neraasen, T. G., and J. C. Holmes. 1975. The cir- to 22 long (Schiller, 1952) and 21-23 long (Spas- culation of cestodes among three species of geese nesting on the Anderson River Delta, Canada. Acta skaya, 1966); it has a longer cirrus, 230 long as Parasitologica Polonica 23:277-289. compared to 140 long (measured from type ma- Schiller, E. L. 1952. Studies on the helminth fauna terial from USNM Helm. Coll.); it has larger and of Alaska. IX. The cestodes of the white-fronted more symmetrical cirrus spines, largest spines 23 goose (Anser albifrons) with the description ofHy- menolepis barrowensis n. sp. Journal of Parasitol- (18-27) long, as compared to 8-10 long (Schiller, ogy 38:32-34. 1952) and 2-13 long (Spasskaya, 1966); it has Spasskaya, L. P. 1966. Cestodes of Birds of the USSR. smaller testes, 88 (80-91) wide, as compared to Hymenolepidae. Institut Zoologia, Izdatl'stvo 129-144 wide (Schiller, 1952) and 150-220 wide Nauka, Moskva. 698 p. Copyright © 2011, The Helminthological Society of Washington