Rochinia annae, Forges & Poore, 2008

Forges, Bertrand Richer de & Poore, Gary C. B., 2008, Deep-sea majoid crabs of the genera Oxypleurodon and Rochinia (Crustacea: Decapoda: Brachyura: Epialtidae) mostly from the continental margin of Western Australia, Memoirs of Museum Victoria 65, pp. 63-70 : 66

Rochinia annae s p. nov.

Figures 1c , 3

Rochinia s p. MoV5119.— Poore et al., 2008: 56.

Rochinia fultoni .— Poore et al., 2008: 56 (colour fig.).

Material examined. Holotype: Australia, WA. Off Two Rocks (31°37.05'S – 31°37.23'S, 114°58.19'E – 115°14.39'E), 364–404 m, 19 Nov 2005 (SS10/2005 004), WAM C400531 (male, 11.9 x 8.6 mm).

Paratypes. Same data as holotype. WAM C400532 (11 specimens), NMV J54179 (87 specimens, smallest is a male of 7.3 x 4.6 mm) .

Othermaterial. Australia.WA. OffKalbarri (27°55.43'S – 27°56.01'S, 113°08.17'E – 113°08.38'E), 252–253 m, 04 Dec 2005 (stn SS10/2005 099), NMV J54058 (1 male). Off Two Rocks (31°36.32'S – 31°37.02'S, 114°58.52'E – 114°58.16'E), 329–370 m, 19 Nov 2005 (stn SS10/2005 006), NMV J54178 (2 ovigerous females 10.5 x 8.2 mm, 8.6 x 6.9 mm). Jurien Bay (29°52.04'S – 29°52.26'S, 114°23.13'E – 114°23.53'E), 414– 401 m, 02 Dec 2005 (stn SS10/2005 078), NMV J54253 (7 juveniles). Off Lancelin (31°00.45'S – 31°00.17'S, 114°49.30'E – 114°49.23' E), 394– 393 m, 01 Dec 2005 (stn SS10/2005 075), NMV J54238 (1 male). Off Bunbury (33°00.30'S – 33°00.07'S, 114°34.16'E – 114°34.30'E), 421– 414 m, 20 Nov 2005 (stn SS10/2005 013), NMV J54073 (male 8.3 x 5.7 mm), J54238 (1 female 6.0 x 4.6 mm). Off D’Entrecasteaux (35°04.11'S – 35°04.14'S, 115°20.10'E – 115°20.53'E), 378–379 m, 21 Nov 2005 (stn SS10/2005 017), NMV J54916 (1 male 9.5 x 10.7 mm, 2 ovigerous females 8.4 x 6.1 mm, 10.5 x 7.4 mm, 2 females 7.6 x 4.7 mm, 7.2 x 5.2 mm) .

Diagnosis. Carapace to 11.9 mm long, pyriform with long diverging pseudorostral spines (one-third length of carapace). Dorsal surface spiny, longest spines as follows: 2 longest and thin branchial spines twice as long as other spines; 1 intestinal spine; 1 long cardiac spine; 1 long mesogastric spine; 2 hepatic spines; in protogastric area, a line of 3 short blunt spines, 2 other spines alongside mesogastric spine; 2 short spines on epigastric area; 2 short spines on lower side of cardiac area.

Cheliped of male short with chelae inflated; merus cylindrical, smooth, with 5 blunt teeth on inferior border, upper anterior angle forming 2 teeth; carpus short and triangular, forming a carina at its interior border; propodus inflated and carinate on upper border; fingers thin with serrulated interior border; dactylus border forming a bump in its first third. Ambulatory legs long and thin; articles cylindrical, pereopod 2 longer than pereopod 1 (pereopod 2 merus reaching little beyond ridge on reflexed carpus of pereopod 1).

Eyes small, protected by cupped postocular tooth; large supraocular tooth. Basal antennal article with long tooth on its antero-external angle; article fused to carapace. Antenna flagellum longer than pseudorostrum; antennule fossae sharp anteriorly. Border of buccal frame expanded laterally. Abdomen of 7 segments. Pleopod 1 of pisid type, distally expanded to an oblique truncate spinose margin, 16 setae in groove (fig. 3).

Distribution. South-western WA slope (27°– 35°S), 252–424 m depth.

Etymology. The species is named in honour of Anna McCallum, who sorted and made preliminary identifications of many of the Decapoda of the Western Australian cruises.

Remarks. Of the 35 species described in the genus Rochinia few have long branchial spines. The only species comparable to R. annae sp. nov. are: R. pulchra ( Miers, 1886) , R. riversandersoni ( Alcock, 1895) , R. sibogae Griffin and Tranter, 1986 , R. galathea Griffin and Tranter, 1986 , R. griffini Davie and Short, 1989 , and R. paulayi Ng and Richer de Forges, 2007 . R. galathea has a long branchial spine but a long and flat hepatic spine, very different from the spine of R. annae . R. sibogae has two very long branchial spines pointing laterally but two other long spines, one intestinal and one cardiac (one long gastric spine in R. annae ). Also, the postocular tooth is distinct from the hepatic spine in R. annae whereas it is a fused plate in R. sibogae . R. pulchra has long branchial spines but a different pattern in the other long spines of the carapace: four spines in the median line (three in R. annae ). R. pulchra possesses pseudorostral spines about three-quarters as long as the carapace but these are one third as long in R. annae . R. riversandersoni is a large species with long branchial spines and long epibranchial spines. R. annae has only a granule at this place. R. paulayi and R. griffini are also large species, very spiny and showing a totally different arrangement of spines from that in R. annae .

Although there is abundant material no specimen is intact and it is not possible to be precise about the relative lengths of pereopods.

The species occurs over a wide geographic range along the south-western WA coast.

Figures

Figure 1. Lateral and dorsal views, scale = 5 mm. a, Oxypleurodon luzonicum (female,NMV J58221).b, Oxypleurodon wilsoni sp. nov. (holotype, WAM C400259). c, Rochinia annae sp. nov. (holotype, WAM C400531). d, Rochinia carinata (male, NMV J53872).

Figure 3. Rochinia annae sp. nov. Male left pleopod 1 (paratype WAM C400531). a, anterior view. b, detail of tip, anterior view. c, detail of tip, posterior view.