Diplocirrus capensis Day, 1961

Salazar-Vallejo, Sergio I. & Buzhinskaja, Galina, 2011, Revision of Diplocirrus Haase, 1915, including Bradiella Rullier, 1965, and Diversibranchius Buzhinskaja, 1993 (Polychaeta, Flabelligeridae), ZooKeys 106, pp. 1-45 : 15-17

Diplocirrus capensis Day, 1961

Diplocirrus capensis Day 1961:509, Fig. 9 a–f; Day 1967:666, Figs. 32.4 e–j; Day 1973:105-107; Milligan 1984:47.9-11, Figs. 47.5-6; Darbyshire and Mackie 2009:96-98, Table 1 (redescr.).

Type material.

The specimens are housed in the South African Museum, Cape Town, but were not made available. Reexamined by Darbyshire and Mackie (2009).

Additional material.

Madagascar. One specimen (SMF-15355), anterior fragment, damaged, Stat. 11 bis, 47 m, 3 Apr. 1970, R. Plante, coll. (6 mm long, 1 mm wide, cephalic cage chaetae 0.3 mm, 15 chaetigers; gonopores in chaetigers 5-12). Two fragments (SMF-15374), Nosy Iranja, Stat. 4, Benne, 17 Sep. 1966, R. Plante, coll. Northwestern Atlantic Ocean. 18 specimens (USNM-51039), damaged, 12 anterior previously dissected or with some parapodia previously removed, and 6 median fragments, off North Carolina, BST 51X (34°20'N, 75°55'W), 165 m, sandy mud, J.H. Day, coll. (larger anterior fragments 6.0-10.5 mm long, 1 mm wide, cephalic cage 0.8-1.0 mm long, 16-28 chaetigers; gonopores not seen).

Description.

(modified from Day 1961, 1967 and combined with data from Darbyshire and Mackie 2009. Data from North Carolina specimens in parenthesis, if they differ): Body muddy brown (golden), anteriorly swollen with segmental lines indistinct, tapering posteriorly with better defined segments. Holotype an anterior fragment, 12 mm long, 2 mm wide, no cephalic cage, 18 chaetigers. Tunic papillated; each papillae short, 8-shaped to long, clavate, basally swollen (lateral papillae longer, cirriform).

Cephalic hood not exposed. Prostomium with four small, black eyes. Palps thick, as long as branchiae. Caruncle projected dorsally, not reaching the posterior margin of branchial plate. Lips corrugated, fused. Nephridial lobes in branchial plate not seen. Branchiae very dark, of two types. Posterior row with four wedge-shaped filaments; anterior row branchiae cirriform, separated in two lateral pairs by the caruncle. Interbranchial lobes not seen. Lamellate region difficult to evaluate.

Chaetigers 1-2 with 2-3 fine notochaetae and 4-6 shorter multiarticulated neurochaetae. Anterior dorsal margin of first chaetiger papillated, as following segments; no other modification. Anterior chaetigers without longer papillae, chaetiger 1 shorter than following ones, chaetal lobes lateral, very close to each other. First 10 chaetigers without marked segmentation; posterior segments better defined. Gonopodial lobes not seen.

Parapodia poorly developed; chaetae emerge from the body wall. Notopodia and neuropodia with papillae longer than other body ones. Noto- and neuropodia close to each other. Median neuropodia lateral, very close to notopodia.

Median notochaetae arranged in a longitudinal line, as long as body width, 10-12 (4-6) per bundle, each with short rings basally, long medially and distally. Neurochaetae multiarticulated hooks from chaetiger 1, arranged in a short J-pattern, 6-8 (3-4) per bundle, each with articles of about the same length, tip falcate.

Posterior end unknown.

Remarks.

Diplocirrus capensis Day, 1961 is closely related to Diplocirrus kudenovi sp. n. and Diplocirrus stopbowitzi Darbyshire & Mackie, 2009 because their bodies do not incorporate sand particles, and by lacking ventrolateral gonopores. However, these two latter species are provided with hemispherical papillae whereas in Diplocirrus capensis papillae are elongate, often basally swollen, but never hemispherical.

The records of Diplocirrus capensis by Day (1973:105-107), and Milligan (1984:47.9-11, Figs. 47.5-6) differ from the typical South African form because they have different body color, cephalic cage, larger lateral papillae, and by the relative numbers of chaetae. They might represent a different species but their description as new species must wait for better specimens. There is a similar, apparently undescribed species in the Mediterranean Sea, which has been recorded as Diplocirrus glaucus by Fauvel (1937:34, non Malmgren, 1867). The materials are damaged (MNHN-406), many chaetae broken, anterior regions smashed or without exposed head, and were collected off Alexandria, Egypt. Better specimens would help clarifiy its affinities with Diplocirrus capensis .

Distribution.

The distribution for the nominal form is apparently restricted to the Cape province, South Africa, in 11 m; it is questionably recorded from North Carolina, 165 m depth.