Haplosyllis agelas Uebelacker, 1982

Lattig, Patricia & Martin, Daniel, 2009, A taxonomic revision of the genus Haplosyllis Langerhans, 1887 (Polychaeta: Syllidae: Syllinae), Zootaxa 2220, pp. 1-40 : 9-10

Haplosyllis agelas Uebelacker, 1982

( Fig. 4 A–E)

Haplosyllis agelas Uebelacker, 1982: 857 –860, fig. 1–9.— Licher, 1999: 280.

Material examined. Bahamas. Holotype USNM 62008; 4 paratypes USNM 62009; 3 paratypes ZMH –P 16467. Grand Bahama Island, from sponge Agelas dispar, 20 m, November 1975.

Description. Body robust, subcylindrical, strongly arched dorsally, flattened ventrally. Length 10–20 mm for 88–117 chaetigers, width 0.6–1 mm, excluding parapodia. Preserved specimens yellow-pale. Dorsal pigmentation and epidermal granules absent. Prostomium subpentagonal, wider than long, with two pairs of small red eyes in trapezoidal arrangement. Median antenna inserted on median part of prostomium, with 19 articles; lateral antennae inserted on anterior margin of prostomium, with 12 articles. Palps twice as long as prostomium, broadly triangular, fused at their bases, but separated all along their length; sensory organs of palps not seen. Single pair of dorso-lateral ciliated nuchal organs between peristomium and prostomium. Pharynx orange, 0.6 mm long, 2.7 mm wide, extending about eight segments. Anteriorly with large tooth and crown of 10 soft papillae. Pharyngeal ciliary ring not seen. Proventricle cylindrical, dark-brown, 1.1 mm long, 2.8 mm wide, extending about nine segments, with 46 muscular cell-rows. Peristomium well defined, shorter than subsequent ones. Dorsal tentacular cirri longer than ventral ones, with 14 and 7 articles respectively. Dorsal cirri broad, similar to antennae and tentacular cirri; first cirri longer than remaining ones (14–20 articles); second short (6–10 articles), third and fourth slightly longer (9–13 and 8–18 articles, respectively), fifth short (6–8 articles). Midbody cirri of similar size (5–10 articles), gradually decreasing to posterior end; longest cirri do not exceed ½ of body width. Posterior dorsal cirri short (2–6 articles). Ventral cirri digitiform, anterior most longer than median and posterior ones. Chaetae bidentate, all similar, but anterior ones smaller ( Fig. 4 A–C). LMF shorter than SW; MJP curved and short; US without denticles; apical teeth similar in length, with wide angle. One or two chaetae per parapodia, sometimes with one or two chaetae non-protruding from parapodial lobe. Usually two stout aciculae per parapodium, one straight and the other slightly curved, with rounded tip upwards directed ( Fig. 4 D–E). Pygidium with two long anal cirri, 10 articles.

Reproduction. Uebelacker (1982) observed two specimens with coelomic oocytes beginning in chaetigers 31 and 33.

Host. Found only in association with the demosponge Agelas dispar Duchassaing & Michelotti, 1864.

Distribution. Bahamas, Grand Bahama Island.

Remarks. Uebelacker (1982) mentioned a slight variation in chaetal morphology due to the presence or absence of additional apical teeth. According to our observations, there is only one type of chaetae all along the body, and the observed variation probably represents broken chaetae.

Figures

FIGURE 4. Haplosyllis agelas. A—anterior chaeta, B—midbody chaeta, C—posterior chaetae; D—midbody acicula; E—posterior body aciculae. Scale bar 20 Μm.