Chapter 7 Planktonic Crustacea Part V Mysidacea References ?刘瑞玉, 王绍武, 2000. 中国动物志节肢动物 门甲壳动物亚门糠虾目 Characteristic features 1 the cephalothorax is not entirely covered by the carapace 2 P Re well developed, Pl rudimentary 3 with statocyst 4 direct development 1 External features 1.1 Partition and metamerism ? cephalothorax ? abdomen 1.2 Appendages ?（1）A 1 ?（2）A 2 ?（3）M, M 1 , M 2 ?（4）P 1-8 (P 1 →Mp, P 2 →Gp） ?（5）Pl 1-5 ，sexusal dimorphism ?（6）Up 抱卵板 Hansenomysis fyllae♀P 2 and P 8 2 Classification >700 species, 2 suborders, 4 families, 43 genera ? 1 shape of the carapace ? 2 with or without gills ? 3 ♀the number of oostegites ? 4 the degree development of Pl ? 5 with or without statocyst Comparison of two suborder in Mysidacea usually presentabsentstatocyst ♀rudimentary，♂one or more pairs modified as accessory copulatory organs ♀♂well developed ♂not modified Pl ♀2-3 pairs♀7 pairsoostegites absentP 2-7 presentbranchiae Suborder Mysida Suborder Lophogastrida 2.1 Suborder Lophogastrida疣背糠虾亚目 2.2 Suborder Mysida糠虾亚目 2.2.1 Mysidae糠虾科 ? Subfamily Siriellinae节糠虾亚科 ? Siriella sinensis中华节糠虾 Subfamily Gastrosaccinae囊糠虾亚科 ? Iiella pelagicus漂浮小井伊糠虾 Pl 3 Re Incision on telson Neomysis kadiakensis Subfamily Mysinae糠虾亚科 ? Neomysis japonica日本新糠虾 ? Acanthomysis longirostris长额刺糠虾 Pl 4 Re A 2 Re antennal scale (鳞片) Comparison of family of Mysidae Neomysis and Acanthomysis GastrosaccusSirielladelegate genus unsegmentedunsegmentedsegmentedUp Re changed but no distinct with distinct apical cleft entiretelson nonoyes Up Re with a well-marked distal suture 2-3 pairs2 pairs3 pairs♀oostegites MysinaeGastrosaccinaeSiriellinae Subfamily features 3 Biology and Significance 3.1 Biology ? 1 distribution ? 2 swarming ? 3 feeding habits ? 4 reproduction 3.2 Significance