Goniada paucidens Grube, 1878

Böggemann, Markus, 2015, Glyceriformia Fauchald, 1977 (Annelida: “ Polychaeta ”) from Lizard Island, Great Barrier Reef, Australia, Zootaxa 4019 (1) : -

Goniada paucidens Grube, 1878

( Figs 16 , 17 E–H)

Goniada paucidens Grube, 1878: 185 .

Material examined. AM W.41212, Lizard Island, Mermaid Cove, North Point, 14°38'46"S 145°27'13"E, coral rubble, 9.5 m, by hand from SCUBA, 7 Sep 2010, CReefs, af/11/82/1.0/0.5, part of proboscis on SEM stub; AM W.44845, MI QLD 2370, cs/20/123/1.3/0.7; AM W.44039, MI QLD 2356 (few), cs/17/105/1.2/0.6, cs/13.5/106/ 1.0/0.5; AM W.46139, fringing reef between Bird Islet and South Island, 12 m, by hand from SCUBA, 1 Aug 1977, cs/10.8/86/1.0/0.5; AM W.46147, reef front between Bird Islet and South Island, 14°41'53"S 145°27'51"E, dead coral, 13 m, by hand from SCUBA, 30 Mar 1995, cs/17.8/108/1.3/0.7; AM W.46137, Lizard Island, north of Coconut Beach, dead reef rock encrusted with filamentous brown algae, 20 m, 17 Jan 1975, cs/ca.15/ca.76/1.0/0.5.

Diagnosis. Proboscis with a few different types of papillae, dorsal ones mainly heart-shaped with pointed tip; numerous H+v/w-shaped dorsal and ventral compound micrognaths; 1–12 pairs of chevrons; 53–60 uniramous chaetigers, following biramous; notochaetae capillaries, neurochaetae compound spinigers.

Description. Body up to 20 mm long with up to 123 chaetigers. Segments uni-annulate, but median part of dorsum usually appears to be bi-annulate.

Conical prostomium consisting of about 8–9 rings; terminal annulus with four biarticulate appendages and basal one with pair of nuchal organs. Pair of subdistal (4th ring) and/or basal subdermal eyes may be present; especially in smaller specimens ( Fig. 16 A).

Proboscis with predominantly heart-shaped papillae with pointed tip on short stalks in more or less longitudinal rows ( Fig. 17 E–F). Macrognaths tri- to quadridentate; 5–10 H+v/w-shaped dorsal and 6–12 H+v/wshaped ventral compound micrognaths, dorsal arc sometimes additionally with four small H- or X-shaped micrognaths in outer position and between other ones. 2–12 chevrons on each side of proboscis ( Fig. 17 G–H).

First segment apodous and achaetous, only with a pair of small lateral cirri ( Fig. 16 A). First chaetigers with only one neuropodial pre- and one postchaetal lobe; second, lower prechaetal lobe developed from chaetiger 2–5; both prechaetal lobes digitiform, upper one always slightly or distinctly longer and broader than lower one; conical to triangular postchaetal lobe always shorter ( Fig. 16 B–C). 55–59 uniramous chaetigers, following parapodia biramous with digitiform to conical notopodial prechaetal lobes and shorter, rounded postchaetal lobes ( Fig. 16 D). From 50th to 60th chaetiger parapodia enlarged and with noto- and neuropodia clearly separated ( Fig. 16 E–G); lobes of about same shape as before; in posterior parapodia notopodial prechaetal lobes, lower neuropodial prechaetal lobes and neuropodial postchaetal lobes shorter and upper neuropodial prechaetal lobes slightly more slender ( Fig. 16 H–I). Dorsal cirri on anterior chaetigers digitiform, about as long as neuropodial postchaetal lobes or slightly shorter ( Fig. 16 B–C); in biramous parapodia more conical and about as long as notopodial prechaetal lobes ( Fig. 16 D–G); in posterior parapodia elongated and more digitiform ( Fig. 16 H–I). Ventral cirri in anterior parapodia digitiform, about as long as neuropodial postchaetal lobes ( Fig. 16 B–G); in posterior parapodia slender and elongated, about as long as upper neuropodial prechaetal lobes ( Fig. 16 H–I).

Noto- and neuropodia each with a single acicula ( Fig. 16 B–I). Notochaetae capillaries. Neurochaetae compound spinigers with blades of different lengths.

Pygidium with dorsal anus and terminal pair of slender, elongated cirri.

Remarks. Previously only specimens with up to six pairs of chevrons have been described.

Distribution. Lizard Island Group; 9– 20 m.

Figures

FIGURE 16. Goniada paucidens Grube, 1878, AM W. 41212 (A), AM W. 44845 (B – I). A. Anterior end with partly everted proboscis, dorsal view; B – I. Anterior to posterior parapodia, posterior view, aciculae suggested, chaetae omitted.

FIGURE 17. Goniada echinulata, AM W. 47203. A – B. Micrograph (A) and SEM picture (B) of larger, elongated conical papillae with distal beak; C – D. Micrograph (C) and SEM picture (D) of chevrons. Goniada paucidens, AM W. 41212. E – F. Micrograph (E) and SEM picture (F) of heart-shaped papillae; G – H. Micrograph (G) and SEM picture (H) of chevrons.