Floresorchestia limicola ( Haswell, 1880 ) Haswell, 1880

Lowry, J. K. & Springthorpe, R. T., 2015, Coastal Talitridae (Amphipoda: Talitroidea) from north-western Australia to Darwin with a revision of the genus Cochinorchestia Lowry & Peart, 2010, Zootaxa 3985 (2), pp. 151-202 : 179

Floresorchestia limicola ( Haswell, 1880) comb. nov.

( Figs 17 , 18 )

Talorchestia limicola Haswell, 1880: 98 , pl. 5, fig. 2.— Stebbing, 1906: 547.— Stebbing, 1910: 645.— Sheard, 1937: 26.— Springthorpe & Lowry, 1994: 128.— Lowry & Stoddart, 2003: 275.— Lowry & Springthorpe, 2009a: 903. Chelorchestia limicola .— Serejo, 2009: 893, figs 1, 2, pl. 6E, F.

Types. Neotype, male, 10.7 mm, AM P.80168, Mermaid Cove, Lizard Island, Queensland, Australia, (14°38.91'S 145°27.26'E), mangrove roots from mangroves behind beach, intertidal, coll. C. Serejo, 3 March 2005, station QLD 1785.

Type locality. Mermaid Cove, Lizard Island, Queensland, Australia (14°38.91'S 145°27.26'E).

Material examined. Male, 8.3 mm, MAGNT Cr018596, female (ovigerous), 6.7 mm, MAGNT Cr018597, 1 male, 1 female, MAGNT Cr018598, mangroves, Jones Creek, Middle Arm, Darwin Harbour, Northern Territory, Australia (12°33.92'S 130°53.845'E), coll. K. Metcalfe, station M 36.

Habitat. Marine supralittoral, mangrove roots from mangroves behind beach or under the leaf litter from around crab holes at back of beach ( Serejo 2009, current study).

Diagnosis. Mandible lacinia mobilis 4-cuspidate. Gnathopod 1 with palmate lobes on merus, carpus and propodus; palm obtuse. Gnathopod 2 propodus palm not reaching along posterior margin; dactylus shorter than palm, blunt distally. Pereopod 4 dactylus similar to pereopod 3, not thickened proximally or notched medially. Epimera 2 with about 12 slits just above ventral margins. Uropod 1 outer ramus without marginal robust setae. Uropod 3 peduncle with 1 robust seta; ramus without marginal robust setae. Telson with 3 dorsolateral and apical robust setae per side.

Remarks. This species was fully described recently ( Serejo 2009) from Lizard Island on the Great Barrier Reef and attributed to the Central American genus Chelorchestia Bousfield, 1984 . Soon after Dang & Le (2011) described Floresorchestia vugiaensis from central Vietnam, but their illustrations did not include vertical epimeral slits for the species. In SEMs of new specimens of C. limicola from near Darwin we observed vertical epimeral slits ( Fig. 17 ) and realized that this was a species of Floresorchestia . We confirm that material from Lizard Island also has vertical slits only on epimeron 2. Six other species have this condition ( F. andrevo Lowry & Springthorpe, 2015 , F. australis Lowry & Springthorpe, 2009b , F. pectenispina ( Bousfield, 1970) , F. pohnpei Lowry & Myers, 2013 , F. samoana ( Bousfield, 1971) and F. serejoae Lowry & Springthorpe, 2015 ). The male second gnathopods of F. l i m i co l a and F. vugiaensis are very similar and they appear to be sister species. We suspect that F. vugiaensis also only has vertical slits on epimeron 2.

The inclusion of F. limicola increases the number of species in the genus to 29.

Distribution. Australia. Queensland: Bowen ( Haswell 1880); Mermaid Cove, Lizard Island, Great Barrier Reef ( Serejo 2009); Middle Arm, Darwin Harbour, Northern Territory (this study).

Figures

FIGURE 17. Floresorchestia limicola (Haswell, 1880), male, 8.3 mm, MAGNT Cr 018596; female (ovigerous), 6.7 mm, MAGNT Cr 018597; Jones Creek, Middle Arm, Darwin Harbour, Northern Territory, Australia. Scale lines represent 0.1 mm.

FIGURE 18. Floresorchestia limicola (Haswell, 1880), male, 8.3 mm, MAGNT Cr 018596; female (ovigerous), 6.7 mm, MAGNT Cr 018597; Jones Creek, Middle Arm, Darwin Harbour, Northern Territory, Australia. Scale line for male G 2 represents 0.5 mm, remainder represent 0.2 mm.