Cyclaspis decora, Corbera, 2008

Corbera, Jordi, 2008, Deep-sea Bodotriidae (Crustacea: Cumacea) from New Caledonia, Fiji and Indonesia, Zoological Journal of the Linnean Society 152 (2), pp. 227-254 : 233-237

CYCLASPIS DECORA SP. NOV. ( FIGS 8–10 )

Type material: Holotype: preadult male dissected in two slides, New Caledonia, BIOCAL, stn DW77, 22°15.32′S, 167°15.40′E, 440 m, 5.ix.1985 (MNHN- Cu1081) . Paratypes: same station than holotype, 1 adult female, 1 adult male, 1 preadult male (MNHN- Cu1082); Stn DW 43, 22°46.21′S, 167°14.50′E, 400 m, 30.viii.1985, 1 preadult female (MNHN-Cu1083). Fiji, BORDAU 1, stn DW1485, 19°02.69′S, 178°29.80′W, 700–707 m, 10.iii.1999, 1 preadult male (MNHN- Cu1084) .

Diagnosis: Carapace nearly twice as long as high, with transverse and oblique carinae. Without a postocular tubercle. Eyelobe elongate reaching the tip of pseudorostrum. Pereopod 1 dactylus longer than carpus. Uropod longer than pleonite 6; exopod slightly longer than endopod, with three small setae terminally.

Description: Preadult male 9.25 mm total length. Carapace ( Fig. 8A, B ) shorter than one-quarter total length, nearly twice as long as high, with transverse and oblique carinae, third dorsal transverse carina runs forward on the side of carapace and reaches the first. Eyelobe long, narrow and without lenses, reaching the tip of pseudorostrum. Antennal notch deep, anterolateral angle acute.

Antennule ( Fig. 8C ), peduncle article 1 shorter than combined length of articles 2 and 3; article 3 longer than article 2; main flagellum 2-articulate, with two aesthetascs, accessory flagellum rudimentary. Right mandible ( Fig. 8D ) with three teeth on pars incisiva, 21 setae between pars incisiva and pars molaris. Maxillule ( Fig. 8E ) palp with two unequal filaments, inner endite with five setae, one of them trifid. Maxilla ( Fig. 8F ), endites with simple and serrulate setae.

Maxilliped 1 ( Fig. 1G ) basis with six simple setae on inner margin, distally produced reaching carpus; carpus with six bi-dentate flattened setae on the inner margin and a long pappose seta on distal outer corner. Maxilliped 2 ( Fig. 1H ) basis longer than rest of appendage, with two plumose setae on distal inner corner and four simple setae on outer margen; carpus longer than merus, with simple and plumose setae on inner margin and a long pappose seta on distal outer corner. Maxilliped 3 ( Fig. 9A ), basis twice as long as rest of appendage, expanded distally reaching half length of merus, with a row of plumose setae on both margins of projection being longer those of inner margin; merus produced distally not reaching the carpo-propodial articulation. Pereopod 1 ( Fig. 9B ), basis shorter than combined length of propodus and dactylus, with a cuspidate seta on inner margin and two plumose setae distally; merus twice as long as ischium; carpus shorter than propodus; dactylus as long as propodus. Pereopod 2 ( Fig. 9C ), basis shorter than rest of appendage; ischium short; merus longer than carpus, with a simple seta on each margin; carpus longer than propodus, with two cuspidate setae on distal corner; dactylus twice as long as propodus, with two long cuspidate setae terminally. Pereopod 3 ( Fig. 9D ), basis longer than rest of appendage, with three pappose setae on margin; ischium with two simple setae on distal margin; merus more than twice as long as ischium and shorter than carpus; carpus with two long simple setae on distal corner; propodus with a long seta on distal corner. Pereopod 4 ( Fig. 9E ), basis as long as rest of appendage, with long pappose setae; merus nearly as long as carpus; carpus and propodus with two and one long simple setae on distal corner, respectively. Pereopod 5 ( Fig. 9F ), basis shorter than rest of appendage, with long pappose setae; merus shorter than carpus; carpus and propodus with three and one long simple setae on distal corner, respectively.

Uropod peduncle ( Fig. 10C ) shorter than pleonite 6, with a pair of plumose setae and five cuspidate setae on inner margin; endopod shorter than peduncle, with five cuspidate setae on proximal half of inner margin; exopod slightly longer than endopod, with three simple setae terminally.

Variability: Main differences between males and females were observed in the uropod armature. In the adult female ( Fig. 10B ) the uropod is very similar to that described for the preadult male and differs only by having six cuspidate setae but no plumose setae on the inner margin of the peduncle. However, in adult male differences are greater. In the peduncle there are long plumose setae but no cuspidate setae ( Fig. 10D ). Similarly, the proximal third of the uropod endopod has long plumose setae in the inner margin followed by five cuspidate setae on the second third.

The preadult male collected in Fiji has a greater number of carinae on the posterior sides of the carapace ( Fig. 10A ) than in females. The other two males assigned to this species and collected at the same station as the holotype are poorly calcified and is not possible to determine if they also have the same ornamentation on the carapace. However, other features such as the structure of pereopod 1 with the long dactylus suggest including this specimen in the same species given the variability of carapace ornamentation as a sexual difference .

Etymology: From Latin decorus, meaning ornament, referring the beautiful sculpture of the carapace.

DEEP-SEA PACIFIC BODOTRIIDAE 237

Remarks: By the dorsal transverse carinae, Cyclaspis decora slightly resembles C. sibogae Calman, 1905 and C. triplicata Calman, 1907 . However, C. decora has a greater number of carinae on the sides of the carapace. Moreover, the uropod peduncle is shorter than pleonite 6 in C. decora while it is longer in C. sibogae and the first lacks the mid-dorsal projection at the hind margin of the carapace, which is present in C. triplicata .

Figures

Figure 1. Cyclaspis variosculpta sp. nov. adult female paratype: A, whole animal in lateral view. Preadult male holotype: B, antenna 1; C, left mandible; D, maxilla 1; E, maxilla 2; F, maxilliped 1; G, maxilliped 2.

Figure 8. Cyclaspis decora sp. nov. adult female paratype: A, whole animal in lateral view. Preadult male holotype: B, carapace in dorsal view; C, antenna 1; D, right mandible; E, maxilla 1; F, maxilla 2; G, maxilliped 1; H, maxilliped 2.

Figure 9. Cyclaspis decora sp. nov. preadult male holotype: A, maxilliped 3; B, pereopod 1; C, pereopod 2; D, pereopod 3; E, pereopod 4; F, pereopod 5.

Figure 10. Cyclaspis decora sp. nov.: A, carapace of a preadult male paratype in lateral view. Variability in the uropod armature: B, adult female paratype; C, preadult male holotype; D, adult male paratype.