The number of zoeal stages in larval development of Nihonotrypaea petalura (Stimpson, 1860) (Decapoda: Axiidea: Callianassidae) from Russian waters of the Sea of Japan Author Kornienko, Elena S. Author Korn, Olga M. Author Golubinskaya, Darya D. text Zootaxa 2015 3919 2 343 361 journal article 10.11646/zootaxa.3919.2.7 d265ac97-e0a7-415e-b683-ba28c02cbe25 1175-5326 238030 497FE0F9-67B0-4070-9026-30C25CB88ED1 Key to the identification of zoeal stages of Nihonotrypaea petalura 1. Uropod absent; antennule uniramous; pleon with five somites.................................................. 2 - Uropod present; antennule biramous; pleon with six somites................................................... 3 2. Eyes sessile; posterior margin of telson with 7+1+7 processes; pereiopods absent............................... zoea I - Eyes stalked; posterior margin of telson with 8+1+8 processes; pereiopods 1 and 2 present...................... zoea II 3. Endopod of uropod unarmed; pleopod buds absent; height of telson nearly equal posterior margin.................zoea III - Endopod of uropod with plumose setae; pleopod buds present; height of telson longer than posterior margin............. 4 4. Endopod of uropod with 6–8 plumose setae; distal segment of antennular peduncle with 4 plumose setae; endopod of antenna equal half of scaphocerite without setae.............................................................. zoea IV - Endopod of uropod with 10–18 plumose setae; distal segment of antennular peduncle with 5–8 plumose setae; endopod of antenna longer than half of scaphocerite without setae......................................................... 5 5. Endopod of antennule shorter than exopod; distal segment of antennular peduncle with 5–6 plumose setae; height of telson 1.5 times longer than posterior margin................................................................... zoea V - Endopod of antennule longer than exopod; distal segment of antennular peduncle with 7–8 plumose setae; height of telson nearly 2 times longer than posterior margin................................................................. 6 6. Endopod of antenna equal scaphocerite without setae; scaphocerite of antenna with 15 inner plumose setae; CL about 2.7 mm...............................................................................................zoea VI - Endopod of antenna longer than scaphocerite without setae; scaphocerite of antenna with 16–18 inner plumose setae; CL about 3 mm ......................................................................................... zoea VII