Revision of the Genus Microphis Kaup (Pisces: Syngnathidae)

The gastrophorine (trunk-pouch) pipefish genus Microphis Kaup is reviewed, and 5 subgenera and 21 subordinate taxa are recognized. All are restricted to the Indo-Pacific region, except for two Atlantic subspecies of M. brachyurus. The genus is characterized by discontinuous superior trunk and tail ridges, by having the lateral trunk ridge confluent with the inferior tail ridge, 9 caudal-fin rays, presence of brood-pouch plates and absence of pouch folds. Juveniles and subadults of some species occur in marine waters, but brooding fish and most others are best represented in freshwaters or low salinity habitats; maximum size approximately 200 mm SL.

The subgenus Coelonotus Peters (without ridges on opercle, with or without supplemental body ridges and keeled scutella, with fewer than 5 subdorsal trunk rings) includes Syngnathus argulus Peters (Comoro Is. to Marquesas Is.) and S. leiaspis Bleeker (Madagascar to Japan). The subgenus Belonichthys Peters (with or without keeled scutella; with longitudinal opercular ridge, supplemental body ridges and more than 5 subdorsal trunk rings) includes Syngnathus fluviatilis Peters (eastern Africa, Madagascar), S. menta Bleeker (Celebes and Philippine Is.), and Doryichthys spinachioides Duncker (Papua New Guinea). The subgenus Microphis Kaup (with longitudinal opercular ridge and fewer than 4 subdorsal trunk rings; without keeled scutella, supplemental opercular ridges or supplemental body ridges) includes Syngnathus deocata Hamilton Buchanan, type-species of the genus Microphis (northern India and Bangladesh), Syngnathus cuncalus Hamilton Buchanan (India, Sri Lanka, Bangladesh), Doryichthys dunckeri Prashad and Mukerji (Irrawaddy R. drainage, Burma), and Microphis cruentus Dawson and Fourmanoir (New Caledonia). The subgenus Oostethus Hubbs (with longitudinal and supplemental opercular ridges, long snout and fewer than 5 subdorsal trunk rings, but without supplemental body ridges or keeled scutella) includes Syngnathus manadensis Bleeker (Indonesia to Taiwan and Solomon Is.), Microphis pleurostictus Peters and M. jagorii Peters (Philippine Is. endemics), Doryichthys insularis Hora (Andaman Is.), and the widespread Syngnathus brachyurus Bleeker. Four subspecies of Microphis brachyurus are recognized: M. b. brachyurus (central Indian Ocean to Japan and Society Is.), M. b. millepunctatus (western Indian Ocean), M. b. aculeatus (tropical eastern Atlantic), and M. b. lineatus (western Atlantic and Pacific terminus of Panama Canal). Lophocampus subgen. nov. (with longitudinal and supplemental opercular ridges, short snout, fewer than 2.5 subdorsal trunk rings and usually with supplemental body ridges and/or keeled scutella) is proposed for the accommodation of Syngnathus retzii Bleeker, the type-species (Indonesia, Philippine Is. to Samoa), Doryrhamphus brevidorsalis de Beaufort (Indonesia, western Caroline Is. to Fiji), Doryichthys ocellatus Duncker (Sri Lanka, Indonesia), and D. caudocarinatus Weber (Irian Jaya). Included taxa are diagnosed, most are illustrated, complete synonymies are given for all subordinate taxa except M. b. lineatus (published elsewhere), distribution maps (based on material examined) are given for Indo-Pacific forms, and a key to subgenera and subordinate taxa is provided.