Paralamprophaea meyeri, 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 : 102-103

Paralamprophaea meyeri n. sp.

Fig. 60

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Type material. Western Pacific, French Polynesia. Holotype ( UF 2158 ), Society Islands , Moorea , West side of Opunohu Pinnacle (17°29’38.76” S, 149°51’43.20” W), rubble and sponges, 10 m, 11 Nov. 2010, C. Meyer, coll.

Description. Holotype (UF 2158) complete, slightly dehydrated especially along posterior region, ventrally bent, posterior region twisted. Body tapered, wider anteriorly, 17 mm long, 2 mm wide (without parapodia), 14 chaetigers; chaetigers 15–16 and pygidium removed for molecular analysis; an anterolateral dissection for observing pharynx jaws, right parapodium of chaetiger 8 removed for observing parapodial features. Body blackish, pigmentation progressively fading off along body; transverse bands interrupted middorsally along chaetigers 1–5, following bands complete, anterior and posterior margins diffuse ( Fig. 60A ); dorsal cirri with brownish cirrophores; midventral dark brownish longitudinal band interrupted by transverse oval pale spots; dark brown spots on parapodial bases ( Fig. 60B ). Most tentacular, dorsal and ventral cirri on site.

Prostomium brownish, slightly longer than wide, slightly wider medially; pale areas include two anterior tapered ones ahead of anterior eyes, three round areas at the level of posterior eyes, and two laterally and posteriorly continued areas behind posterior eyes ( Fig. 60C ). Lateral antennae with ceratophores distinct, antennae longer than prostomium and palps; palpophores 2–3 times longer than palpostyles. Median antenna short, almost reaching anterior prostomial margin, inserted between anterior eyes.

Eyes brownish, anterior eyes semilunar, slightly darker, larger and more distant to each other than posterior round eyes, in lateral view eyes clearly separated ( Fig. 60C ).

Nuchal organs lobes L-shaped, fully exposed, mostly unpigmented, with blackish areas basally in the outer sides, and as a thin longitudinal line along anterior margin; lateral branches reaching prostomial lateral margins, expanded subdistally, slightly directed anteriorly; lateral ciliated bands barely visible dorsally. Tentacular cirri twisted, almost complete, longer ones reaching chaetiger 8. Lateral cushions low, entire, longitudinal striae distinct.

Pharynx not exposed, inner features observed through dissection. Anterior margin smooth, lateral vesicles not seen. Jaws golden, exposed, upper jaw double, lower one single transverse bar. Basal ring with series of large papillae, collapsed by invagination, about 6 papillae per series.

Dorsal cirri with tips eroded, as long as body width (including parapodia). Chaetigers 1–4 without notochaetae; notochaetae present along chaetigers 5–14, up to 20 per bundle, delicate, arranged in bundles, notochaetae subdis- tally denticulate, denticles coarse. Notacicular lobes small, blunt, digitate; neuracicular lobes semicircular, twice wider than long ( Fig. 60D ). Neurochaetae about 30 per bundle, blades decreasing in size ventrally, bidentate, 3–6 times longer than wide, guards denticulate, approaching subdistal tooth ( Fig. 60E ).

Posterior region tapered. Preanal and pygidium unknown. Whitish gonad fragments expelled by posterior end dissection. Oocytes in ovary, each about 100 µm.

Etymology. This species name is to honor Dr. Christopher P. Meyer, Director of the Moorea Biocode Project, National Museum of Natural History, Smithsonian Institution, in recognition of his initiatives in generating COIbarcode libraries for different localities, and because he collected the holotype. The species-group name is a noun in the genitive case ( ICZN 1999, Art. 31.1.2).

Remarks. Paralamprophaea meyeri n. sp. differs from the other species having notochaetae from chaetiger 5, and especially by its pigmentation pattern. Its transverse bands are blackish, not brownish, despite being in ethanol for nearly a decade, and the bands are not continuous, especially along the first few chaetigers, being middorsally interrupted by large oval pale areas connecting to each other middorsally. Further, the venter has a longitudinal middle band progressively thinner and paler, and some ventral round spots in the base of neuropodia.

Distribution. Moorea, French Polynesia, in mixed bottoms at 10 m depth.

Figures

FIGURE 60. Paralamprophaea meyeri n. sp., holotype (UF 2158). A. Dorsal view. B. Ventral view. C. Anterior end, dorsal view. D. Chaetiger 8, right parapodium, anterior view. E. Same, neurochaetae (insets: longer and shorter neurochaetal blades). Scale bars: A, B: 2 mm, C: 0.4 mm, D: 0.2 mm, E: 70 µm.