Berkeleyia weddellia, Blake, James A., 2017

Blake, James A., 2017, Polychaeta Orbiniidae from Antarctica, the Southern Ocean, the Abyssal Pacific Ocean, and off South America, Zootaxa 4218 (1), pp. 1-145 : 14

Berkeleyia weddellia new species

Figure 4

Material examined. Antarctica , Weddell Sea, ANDEEP III, R/ V Polarstern, Sta. PS 67/078- 4, 21 Jan 2005, 71°9.49′S, 13°59.92′W, 2164 m, holotype ( ZMH P-27782).

Description. A single incomplete specimen 4 mm long, 0.4 mm wide across thorax for 28 setigers. Color in alcohol: light tan, without pigment. Thoracic region with 11 setigers; body cylindrical in cross section, weakly flattened dorsally, abdominal segments cylindrical in cross section.

Prostomium conical, triangular in shape, tapering to narrow pointed apex ( Fig. 4 A–B); without eyespots; nuchal organs paired notches on anterior margin of peristomium ( Fig. 4 A). Peristomium with a single achaetous ring, slightly narrower than setiger 1, but similar in length.

Thorax with short, conical notopodial postsetal lobes from setiger 1, increasing in length and shape over thoracic region, initially minute, rounded, then becoming triangular at base narrowing to pointed apex by setiger 8 ( Fig. 4 A); neuropodia similar to notopodia with elongate postsetal lobe with triangular base near end of thoracic region; abdominal segments denoted by shift of parapodia dorsally, and abrupt change in notopodia to long, narrow, fingerlike postsetal lobe ( Fig. 4 C); abdominal neuropodia becoming thickened, with short ventral cirrus ( Fig. 4 C).

Thoracic setae all long, crenulated capillaries; abdominal notopodia with crenulated capillaries and 1–2 delicate furcate setae; each furcate seta with 5–6 thin needles between tynes and rows of fine barbs on shaft ( Fig. 4 D). Abdominal neuropodia with 2–3 capillaries and 2–3 long projecting smooth spines with entire pointed tips ( Fig. 4 C, E–F).

Branchiae from setiger 18, short at first, becoming full size by setiger 20, each branchia thick, short with rounded apex ( Fig. 4 C). Pygidium unknown.

Remarks. See comments under B. abyssala n. sp.

Etymology. This species is named for the collecting locality in the Weddell Sea, Antarctica .

Distribution. Weddell Sea Basin, Antarctica, 2164 m .

Figures

FIGURE 4. Berkeleyia weddellia n. sp. Holotype (ZMH P- 277823). A, anterior end, left lateral view B, same, dorsal view; C, abdominal parapodium, posterior view; D, furcate seta; E – F, abdominal neuropodial spine and capillary.