Demaorchestia joi (Stock & Biernbaum, 1994) com. nov.

(Fig. 6)

Talorchestia crassicornis Derzhavin, 1937: 108, pl. 3, 1. [homonym of Platorchestia crassicornis (Costa, 1867)].— Gurjanova, 1951: 812, fig. 566.

Orchestia platensis .—? Iwasa, 1939: 257, figs 1–3, pl. IX.— Bulycheva, 1957: 159–162, figs 57a–b.

? Talorchestia crassicornis .— Kussakin, 1975: 66, table 1 (species list).).

Platorchestia crassicornis .— Bousfield, 1982: 26.— Jo, 1988: 161, figs 5–7, 9a, c, e, 10d, e [ D. joi comb. nov.].

not Platorchestia crassicornis (Costa 1867) .

Platorchestia joi Stock & Biernbaum, 1994: 800 (replacement name for P. crassicornis (Derzhavin, 1937), junior homonym of P. crassicornis (Costa, 1867)).— Stock, 1996: 156.— Serejo, 2004: 20, table 2.

? Platorchestia crassicornis .— Ryu et al., 2012: 716, table 4, 719, 726, appendix 1 (checklist).

? Platorchestia platensis .?— Kim & Kim, 1987: 18, 19, fig. 16A–G.

Not Platorchestia joi .— Miyamoto & Morino, 2004: 69, key, 70, figs 1–3, 15 (= D. pseudojoi sp. nov.).

Non-Taxonomic Citations

Platorchestia crassicornis .— Kim & Kim, 1993: 946, appendix 1 (phylogeny).— Tsubokura, Kikuchi & Nakao, 1998: 626, 627, table 1, fig. 2, 628, 629, 630, fig. 4, 631, fig. 5, table 2, 632, fig. 6, table 3, 633, table 4, 636, fig. 11c (gill morphology).— Hong & Yoon, 2000: 151, fig. 7, 152, fig. 8, 153, fig. 9, 154, table 1, appendix (ecology).— Nanami et al., 2005: 169, table 1 (ecology).— Lisitsyna, 2011: e-7 (intermediate host).

Platorchestia joi .— Wildish & Radulovici, 2019: 2415, table 1, 2422, table 4, 2426, table 6 (zoogeography).

Types. None selected.

Type locality. Posyet Bay, Peter the Great Gulf, Russia ; Bay of Castries, Coast of Tartary, Russia ; Suifin River, Amur Bay and Gulf of Transfiguration, Sea of Japan .

Ecological type. Beach-hoppers or marsh-hoppers.

Habitat. Sandy beaches.

Size. Male, 12.5 mm.

Diagnosis. Based on Jo (1988).

Labium with vestigial inner lobes. Pereopod 4 dactylus, thickened proximally with notch midway along posterior margin. Epimeron 3 posterior margin minutely serrate.

Remarks. Demaorchestia joi and D. pseudojoi are very similar. They differ as follows: labium with vestigial inner lobes (absent in D. pseudojoi); gnathopod 1 carpus length more than 2 × width (less than 2 × width in D. pseudojoi); pereopod 4 dactylus thickened proximally with notch halfway along posterior margin (dactylus short with mini-wavy posterior margin in D. pseudojoi).

Distribution. Russia. Posyet Bay, Patroclus Bay, Chikhachyova Bay (as de Castries Bay), (Derzhavin 1937). Korea, Japan (Kim & Kim 1987 and Jo 1988).