Paralamprophaea crosnieri, Salazar-Vallejo, 2020

Salazar-Vallejo, Sergio I., 2020, Revision of Leocrates Kinberg, 1866 and Leocratides Ehlers, 1908 (Annelida, Errantia, Hesionidae), Zootaxa 4739 (1), pp. 1-114 : 92-94

Paralamprophaea crosnieri n. sp.

Fig. 53

urn:lsid:zoobank.org:act:BD71540B-2B16-409A-A57E-2690A68E6D91

Type material. Madagascar. Holotype ( MNHN A861 ), Sta. P 4 (15°24’30” S, 46°02’00” E), 250–265 m, 7 Nov. 1972, A. Crosnier, coll.

Description. Holotype (MNHN A861) slightly damaged, complete. Body obconic, 34 mm long, 4 mm wide; dorsum with transverse brownish bands with anterior and posterior margins well defined ( Fig. 53A ), pigmentation paler posteriorly. Venter pale. Right parapodium of chaetiger 8 removed for observing chaetal features.

Prostomium slightly wider than long, lateral margins parallel ( Fig. 53B ). Lateral antennae with distinct ceratophores, markedly longer than prostomium and palps; palpophores slightly longer than palpostyles. Median antenna directed posteriorly, short, not reaching anterior prostomial margin, inserted between eyes.

Eyes brownish, round, anterior eyes twice larger and more distant to each other than posterior eyes ( Fig. 53A ).

Nuchal organs lobes markedly surpassing lateral prostomial margins. Lateral ciliated bands visible dorsally. Longest tentacular cirri without tips, reaching chaetiger 8. Lateral cushions barely projected, bifid along most body segments; longitudinal striae visible.

Peristomium with three dorsal tubercles, dorsolateral ones truncate, not reaching the level of middorsal tubercle; ventrally with shorter lateral tubercles and about 16 ventral, round cushions ( Fig. 53C, D ).

Pharynx fully exposed ( Fig. 53C ). Anterior margin smooth. Jaws brownish, upper jaw double, lower one transverse plate, without lateral transparent blades. Lateral vesicles not seen, but left pharynx side laterally expanded into a blunt cone. Basal ring smooth, without papillae.

Dorsal tentacular cirri damaged, some without tips, middle segments with cirri at least twice longer than body width (including parapodia). Chaetigers 1–4 without notochaeetae; notochaetae present along chaetigers 5–16; notacicular lobes basally swollen, slightly projected into a hemispheric short lobe ( Fig. 53E ); neuracicular lobes blunt, wider than long. Notochaetae about 20 per bundle, subdistally denticulate, denticles coarse. Neurochaetae about 30 per bundle, some blades missing, blades decreasing in size ventrally, bidentate, 2–7 times longer than wide, guards approaching subdistal tooth ( Fig. 53 , insets).

Posterior end damaged, tapered into a truncate lobe. Prepygidial segment with dorsal cirri 5–6 times longer than ventral ones. Pygidium with anus terminal, anal cirri damaged, reaching chaetiger 11.

Oocytes not seen, perhaps there were only testis, or gonads damaged.

Etymology. This species name is after Alain Crosnier, a famous French carcinologist, who kindly invited me in 1999 to process the material in the Paris Museum from the Indian and Western Pacific regions, the so-called Musorstom Expeditions ( Salazar-Vallejo 1999). He was personally involved in many ambitious sampling programs in Western Africa, Madagascar, and several archipelagos in the Western Pacific. The 1999 visit allowed me to start studying the extensive and impressive Paris collections, and because of his personal support and with funding from the museum, a series of research visits have helped me do a better taxonomic work. This is a modest means to thank him for his kind support, and especially because he collected the holotype.

Remarks. Paralamprophaea crosnieri n. sp. resembles P. diplognatha ( Monro, 1926) n. comb. from the China Sea, and P. leslieae n. sp. from Kiribati because they have transverse brownish bands along body, each with welldefined anterior and posterior margins. Their main difference is the shape of the peristomial dorsolateral tubercles. In P. crosnieri they are truncate, whereas they are lobate in P. diplognatha , and hemispherical in P. leslieae . The suspicion that these three species would belong to the same one, with these tubercles reflecting a progression in size depending on body size, cannot be sustained. The smaller species, P. diplognatha and P. leslieae , have bodies of similar size (13–22 mm vs 12–19 mm), but the shape of the dorsolateral tubercles does not change with size; further, the holotype of P. crosnieri is the largest specimen (34 mm long) but has truncate tubercles.

Distribution. Only known from the type locality, in Madagascar, in 250–265 m depth.

Figures

FIGURE 53. Paralamprophaea crosnieri n. sp., holotype (MNHN A861).A. Anterior region, dorsal view. B. Anterior end, dorsal view, SAS (*: dorsolateral tubercle). C. Same, ventral view. D. Anterior region, right lateral view (*: dorsolateral tubercle). E. Chaetiger 8, right parapodium, anterior view (insets: notacicular lobe, and smallest and larger neurochaetal blades). Scale bars: A: 1.5 mm, B: 0.6 mm, C: 0.9 mm, D: 0.7 mm, E: 0.8 mm.