On a small collection of amphipods (Crustacea, Amphipoda) from Chilika Lake with the description of three new species and a new genus Author Thacker, Dimple 0000-0003-3101-0028 Animal Taxonomy and Ecology Laboratory, Department of Life sciences, Hemchandracharya North Gujarat University, Patan- 384265, Gujarat, India dimplethacker789@gmail.com Author Myers, Alan A. 0000-0003-3256-2123 School of Biological, Earth and Environmental Sciences, University College Cork, Cork Enterprise Centre, Distillery Fields, North Mall, Cork, Ireland bavayia@gmail.com Author Trivedi, Jigneshkumar N. Animal Taxonomy and Ecology Laboratory, Department of Life sciences, Hemchandracharya North Gujarat University, Patan- 384265, Gujarat, India Author Mitra, Santanu 0000-0002-3247-9293 Animal Taxonomy and Ecology Laboratory, Department of Life sciences, Hemchandracharya North Gujarat University, Patan- 384265, Gujarat, India & Zoological Survey of India, F. P. S. Building, 27 J. L. Nehru Road, Kolkata- 700016, West Bengal, India & Animal Taxonomy and Ecology Laboratory, Department of Life sciences, Hemchandracharya North Gujarat University, Patan- 384265, Gujarat, India & Animal Taxonomy and Ecology Laboratory, Department of Life sciences, Hemchandracharya North Gujarat University, Patan- 384265, Gujarat, India santanuzsi@gmail.com text Zootaxa 2024 2024-05-01 5446 3 383 404 http://dx.doi.org/10.11646/zootaxa.5446.3.4 journal article 10.11646/zootaxa.5446.3.4 1175-5326 11101909 95C3BE52-AA7A-48BE-A889-6ADD280B1792 Chilikorchestia chiltoni sp. nov. ( Figs. 2b & 6–8 ). Material examined. Holotype male, 10.5 mm ( LFSC .ZRC-201), Honeymoon Island , Chilika Lake ( 19°33'17"N 85°08'39"E ), Odisha , India , 2 September , 2018, coll. D. Thacker. Paratypes , 1 male , 11 mm , 1 female , 4.5 mm ( LFSC .ZRC-202), same data as holotype . Etymology. The new species is named in honor of Charles Chilton, who worked as a Professor of Zoology at Canterbury University College, New Zealand and made a significant contribution to crustacean taxonomy. Charles Chilton was also a first researcher to publish a paper on amphipod diversity of Chilika Lake. Description. Based on holotype male ( 10.5 mm ) and paratype female ( 4.5 mm ). Head. Eyes medium, round. Antenna 1 slightly extending the distal end of the antenna 2 article 4 ( Fig. 6 : A1). Antenna 2 less than half of the length of the whole body; peduncular articles moderately incrassate; peduncular article 5 1.6 x as long as article 4; article 5 with some small robust setae ( Fig. 6 : A2). Labrum distal margin rounded with a row of small setae ( Fig. 6 : Lb). Labium with distally setose rounded plates ( Fig. 6 : L). Mandible left lacina moblis 5 dentate ( Fig. 6 : Md). Maxilla 1 vestigial with only 1 article. outer plate with 8 dentate setae; inner plate with 2 plumose setae ( Fig. 6 : Mx1). Maxilla 2 inner plate with a plumose seta on anterodistal corner ( Fig. 6 : Mx2). Maxilliped palp article 2 distomedial lobe well-developed; article 4 reduced, button shaped ( Fig. 6 : Mxp). FIGURE 5. Parhyale kalinga sp. nov. , male holotype (LFSC.ZRC-199): 7 mm, paratype female (LFSC.ZRC-200): 7 mm, Kalupada Ghat, Chilika Lake, (19°52'27"N 85°24'26"E), Odisha, India. Scale bars—0.5 mm. Pereon. Gnathopod 1 subchelate; coxa triangular, narrowing distally; basis 1.2 x as long as carpus; ischium subquadrate; merus shorter than carpus; carpus and propodus lobate on the posterodistal corner, palm with 4 robust setae; dactylus simplidactylate, subequal to palm ( Fig. 7 : G1). Gnathopod 2 subchelate, gill lobate; coxa subquadrate, posterior margin with a central shelf, ventral margin with few small hairs on posterior half, ventral margin with irregularly placed small robust setae; basis twice as long as broad, posterior margin with 4 small robust setae; ischium small; carpus small subrectangular; propodus oval, palm transverse with several small robust setae and a long protuberance at the posterodistal corner; dactylus longer than palm, fits into the groove formed on the protuberance ( Fig. 7 : G2). Pereopod 3–7 bicuspidactylate ( Figs. 7 : P3–P7). Pereopod 3 coxa subquadrate; basis long with robust setae on both margins; merus 1.5 x as long as carpus; propodus subequal to carpus ( Fig. 7 : P3). Pereopod 4 smaller than pereopod 3; basis long with robust setae on both margins; merus 1.6 x as long as carpus; propodus 1.2 x as long as carpus ( Fig. 7 : P4). Pereopod 5 basis expanded; merus subequal to carpus; propodus 1.3 x as long as carpus ( Fig. 7 : P5). Pereopod 6–7 similar, except pereopod 6 basis oval were as pereopod 7 basis subquadrate ( Figs. 7 : P6 & P7). FIGURE 6. Chilikorchestia chiltoni gen. nov. sp. nov., male holotype (LFSC.ZRC-201): 10.5 mm, Honeymoon Island, Chilika Lake, (19°33'17"N 85°08'39"E), Odisha, India. Scale bars—0.3 mm. Pleon. Uropod 1 peduncle longer than rami with 7 robust setae in two margins, distolateral robust setae present, small, with simple tip; exopodite subequal to endopodite, without marginal robust setae; endopodite with 3 robust setae on inner margin ( Fig. 7 : U1). Uropod 2 peduncle little longer than rami, with 5 robust marginal setae; endopodite subequal to exopodite, with 2 marginal setae on inner margin; exopodite with 4 robust setae in two margins ( Fig. 8 : U2). Uropod 3 uniramous; peduncle longer than ramus with 2 robust setae; ramus narrowing distally ( Fig. 8 : U3). Telson slightly longer than broad, apically notched, with 5–6 robust setae on each lobe ( Fig. 8 : T). FIGURE 7. Chilikorchestia chiltoni gen. nov. sp. nov., male holotype (LFSC.ZRC-201): 10.5 mm, Honeymoon Island, Chilika Lake, (19°33'17"N 85°08'39"E), Odisha, India. Scale bars—1.0 mm. Female (sexually dimorphic characters). Gnathopod 1 parachelate; posterior margin of carpus and propodus without lobe; propodus subrectangular. Gnathopod 2 mitten-shaped. Remarks. This is the first record of a member of the Plarorchestiinae occurring in India . Previous records of Platorchestia platensis (Krøyer, 1845) from India ( Barnard, 1935 , Dev Roy et al. , 2009 , Surya Rao, 1972 , Thilagavathi et al. , 2013 ) are erroneous. Distribution. Currently known only from the type locality.