Caulleriella moralesensis, Dean, Harlan K. & Blake, James A., 2007

Dean, Harlan K. & Blake, James A., 2007, Chaetozone and Caulleriella (Polychaeta: Cirratulidae) from the Pacific Coast of Costa Rica, with description of eight new species, Zootaxa 1451, pp. 41-68 : 58-59

Caulleriella moralesensis sp. nov.

Figure 10 A–D.

Material Examined. Costa Rica, Golfo de Nicoya. Holotype: Punta Morales, Playa Blanca, 10°04'N, 84°58'W, lower intertidal zone, muddy sand, 20 Dec 1986, ( MCZ 67153). Paratype: Punta Morales, Playa Blanca, 10°04'N, 84°58'W, lower intertidal zone, muddy sand, 20 Dec 1986, ( MCZ 68796, SEM preparation).

Holotype 12.9 mm long, 0.5 mm wide for 99 setigers, paratype (SEM preparation) 15.3 mm long, 0.3 mm wide for 93 setigers. Body elongate, anterior region slightly wider than middle and posterior regions, weakly flattened dorsoventrally, remainder of body circular in cross-section; setigers short in anterior region, longer in middle and posterior setigers. Notopodia and neuropodia widely separated; anterior region with dorsal depression between two upraised notopodial lobes forming shallow mid-dorsal groove extending to setiger 8; middle and posterior parapodia low ridges; shallow mid-ventral depression extending length of body. Pygidium a simple rounded lobe (Fig. 10C), anus ventral. Color in alcohol light tan.

Prostomium short, tapered with pair of small, rounded nuchal organs located laterally beneath overlying peristomial crest (Fig. 10A B). Peristomium large, overhanging much of prostomium dorsally; with three annulations, anterior annulation approximately 3× length of second annulation, second annulation approximately 2× length of third, with dorsum of third annulation extending posteriorly onto setiger 1. Dorsal tentacles arising from posterior margin of third annulation. First setiger reduced dorsally due to encroachment of peristomium. First and subsequent pairs of branchiae emerging dorsal to notopodial fascicles, posterior half of body abranchiate.

Notosetae of setigers 5–7 unilimbate capillaries, single bidentate notopodial hook present from setiger 23 accompanied by four capillaries; next setiger with three hooks and two capillaries, subsequent setigers with pair of hooks accompanied by 1–2 capillary setae, continuing through far posterior setigers (Fig. 10D). Neuropodia with short, slightly curved, bidentate hooks accompanied by capillaries; setiger 1 with row of seven bidentate hooks accompanied by four capillaries similar to those of notopodia, by setiger 4 only two capillaries accompany the seven hooks, midbody and far posterior neuropodia with three hooks accompanied by 1–2 thin capillaries (Fig. 10D). Notopodial hooks slightly curved, bidentate, neuropodial hooks shorter than notopodial hooks, bidentate with distally directed subequal teeth.

Methyl green staining pattern. Prostomium and pygidium unstained, remainder of body uniformly light blue green.

Habitat. Known only from muddy sand in the lower intertidal zone of Punta Morales.

Remarks. Caulleriella moralesensis sp. nov. is similar to C. alata from the Irish coast, both in the first occurrence of notopodial and neuropodial hooks and in the presence of capillary setae accompanying the neuropodial hooks. C moralesensis sp. nov. is a much smaller species, however, than C. alata which is 10–12 mm in length for 100–110 setigers ( Southern 1914). Additionally, the hooks of C. alata are limbate while those of C. moralesensis sp. nov. are smooth and alimbate.

Etymology. This species is named for the collecting site off Playa Blanca, Punta Morales, Costa Rica.

Caulleriella moralesensis A. Lateral view of anterior end B. Dorsal view of anterior end C. Pygidial region, left lateral view D. Posterior setiger, anterior view. Scale bars: A,B = 0.2 mm, C,D = 0.05 mm. a = annulations, no = nuchal organ.