Platorchestia Bousfield 1982

Platorchestia Bousfield, 1982 Platorchestia Bousfield, 1982: 26; Jo 1988: 160; Richardson 1991: 186; Morino and Ortal 1995: 825; Miyamoto and Morino 2004: 68; Myers and Lowry 2023: 486. Type species. Platorchestia platensis (Krøyer, 1845), original designation. Diagnostic description. (modified from Myers and Lowry 2023) Antenna 1 short, not longer than article 4 of antenna 2 peduncle. Antenna 2 peduncular article 3 without ventral plate; articles 4 and 5 occasionally incrassate in males. Maxilliped palp article 2 with distomedial lobe; article 4 reduced, button-shaped. Gnathopod 1 sexually dimorphic; subchelate; posterior margin of carpus and propodus each lobe covered in palmate setae; dactylus cuspidactylate. Gnathopod 2 subchelate in male, mitten-shaped in female; basis narrow or slightly expanded; propodus palm posterodistal corner without protuberance. Pereopods 3–7 cuspidactylate. Pereopod 7 occasionally incrassate in male. Uropod 1 outer ramus without marginal robust setae. Telson with apical and marginal robust setae. Species composition. Platorchestia contains 13 species: P. ano Lowry & Bopiah, 2013; P. aquaticus sp. nov.; P. crassicornis (Costa, 1867); P. exter Myers & Lowry, 2023; P. griffithsi Myers & Lowry, 2023; P. munmui Jo, 1988; P. negevensis Myers & Lowry, 2023; P. oliveirae Myers & Lowry, 2023; P. pachypus (Derzhavin, 1937); P. pacifica Miyamoto & Morino, 2004; P. paraplatensis Serejo & Lowry, 2008; P. platensis (Krøyer, 1845); P. smithi Lowry, 2012. Remarks. Miyamoto and Morino (2004) established three groups of Platorchestia based on the presence or absence of sexual dimorphism. Lowry and Myers (2022) established the new subfamily Platorchestiinae, which accommodates 15 genera, including Platorchestia. The Platorchestia sensu stricto is equivalent to Group 1 of Miyamoto (antenna 2 and pereopods 6 and 7 are strongly sexually dimorphic and represented by supralittoral species). Subsequently, Myers and Lowry (2023) described three new Platorchestia species and provided the diagnostic characteristics as antenna 2 sexually dimorphic by articles 4 and 5, which are generally incrassate in males and pereopod 7 often incrassate in male articles 5–7. The combination of antenna 2 and pereopod 7 incrassate was classified into Group 1 and Group 2 by Miyamoto and Morino (2004).