Polycirrus boholensis Grube, 1878

Nogueira, João Miguel Matos, Hutchings, Pat & Carrerette, Orlemir, 2015, Polycirridae (Annelida, Terebelliformia) from Lizard Island, Great Barrier Reef, Australia, Zootaxa 4019 (1), pp. 437-483 : 477-479

Polycirrus boholensis Grube, 1878

( Fig. 23 )

Polycirrus boholensis Grube 1878: 242 –243, pl. XIII, fig. 7.

Polycirrus boholensis . —Hutchings & Glasby 1986: 334–336, fig. 6g –k.

Material examined. AM W.44955, MI QLD 2423, complete specimen damaged at posterior thorax, ~ 7 mm long, 1 mm maximum width, gravid; AM W.44960, MI QLD 2424; AM W.44521, MI QLD 2390 (2).

Description. Transverse prostomium attached to dorsal surface of base of upper lip; basal part as thick, curved to horseshoe-shaped crest across dorsum, extending laterally and posteriorly, covering segment 1 laterally and terminating lateral to lower lip; poorly developed distal part, as low lobe of uniform length throughout, at base of upper lip ( Fig. 23 A–D). Buccal tentacles of two types, both spatulated at tips, with deeper groove, long ones relatively short, with thinner uniformly cylindrical peduncle before spatulated tip ( Fig. 23 A–D). Peristomium forming lips; short, hood-like upper lip, distinctly broader than high, slightly convoluted; short, swollen lower lip, button-like ( Fig. 23 B, D). Segment 1 reduced, visible mid-dorsally and ventrally, laterally covered by expanded prostomium; segment 2 reduced, visible all around; body anteriorly swollen, segments progressively wider until segment 8, and progressively longer until segment 10, then with swollen posterior thorax, abruptly tapering posteriorly to uniformly cylindrical posterior body, beginning from the termination of notopodia; large anterior abdominal segments, with thin body wall and poorly marked segmentation, posterior body with clearly defined, compacted segments ( Fig. 23 A–D). Highly papillated ventro-lateral pads, present from segment 2 to segments 10– 12, last pair distinctly less conspicuous ( Fig. 23 B–D). Notopodia extending for 11–16 segments; remarkably elongate, bilobed notopodia, lobes of equal size, first pair shorter ( Fig. 23 A–D). Narrowly-winged, acicular chaetae in anterior row of notochaetae, pinnate chaetae in posterior row, only pinnate at distal third; chaetae from anterior row much shorter, tips barely protruding from parapodial lobes ( Fig. 23 E–F). Neuropodia beginning from first segment after notopodia terminate, varying according with number of pairs of notopodia present; neuropodia as short, raised pinnules ( Fig. 23 A–D). Type 2 uncini throughout, elongate prow and heel, the latter obliquely directed downwards, crest with single elongate and sharp tooth in first row of secondary teeth above main fang, surrounded by crown of minute teeth at base, and elongate neck ( Fig. 23 G). Nephridial and genital papillae anterior to bases of all notopodia, except for last 1–2 pairs, those of segments 6–9 larger ( Fig. 23 B, D). Pygidium smooth to crenulate, with rounded ventral papilla ( Fig. 23 A, C).

Remarks. The holotype of P. boholensis is in poor state of preservation, but matches the description above in all aspects, except for not having conspicuous nephridial and genital papillae (Glasby & Hutchings 2014). This species has previously been found in Australia, among material from Queensland, including Lizard Island and other regions of the GBR, but Australian specimens have nephridial papillae extending until the termination of notopodia (Hutchings & Glasby 1986). Considering the type locality is in the Philippines, we agree with Hutchings & Glasby (1986) and Glasby & Hutchings (2014) in that this species also occurs in northeastern Australia, and interpret the absence of nephridial and genital papillae on the holotype as most likely due to the poor state of preservation of that specimen.

Habitat. In amongst coral rubble on outer reef in shallow water.

Type locality. Bohol, Philippines.

Distribution. Philippines to northeastern Australia.

Figures

FIGURE 23. Polycirrus boholensis, AM W. 44955. A – B. Entire worm, dorsal and ventral views (anteriorly), respectively; C – D. Close ups of the anterior end, dorsal and ventral views, respectively; E – F. Progressively higher magnifications of the notochaetae of segment 7, arrows point to tip of notochaeta from anterior row; G. Uncini, mid-abdominal segment. Numbers refer to segments. Abbreviations: ll = lower lip, P = basal part of prostomium, ul = upper lip, * = distal part of prostomium. Scale bars: A – B = 300 µm, C – D = 200 µm, E = 30 µm, F = 15 µm, G = 10 µm.