Smithsonian National Museum of Natural History

Original Description
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“Pseudoscalibregma bransfieldia (Hartman, 1967)
n. comb.
Figs. 28a-28c

Eusclerocheilus bransfieldia Hartman, 1967 p. 130.

Material. Weddell Sea, in 412-659 m: Station 69­2 (1 specimen); 68-8 (8 specimens); 69-10 (1 speci­men).

Description. An individual from station 69-8 (USNM 46974) measures 10-14 mm long and 3.32 mm wide and consists of an achaetous peristomium with 14 thoracic and 16 abdominal setigers and 1 posterior asetigerous segment. The body is widest at setigers 6-7 and tapers to a slender posterior end. The epithelium of the first 1-5 setigers is smooth; thereafter, through setigers 6-14 it is gradually areolated, and in the abdominal region it is biannu­lated. The pygidium is a plain ring.

The prostomium diverges anteriorly as a pair of frontal antennae (Figure 28a); a flat semicircular crest occupies the postmedian space between a pair of nuchal organs. The oral aperture is a broadly expanded triangular ventral area between the prostomium and peristomium that extends posteriorly as an oral field to setiger 2.

Thoracic segments have biramous fascicles of long slender capillary setae accompanied by one or more furcate setae in each ramus. Notopodia and neuropodia have broad flat lobes located above and below the emerging setae. A conspicuous oval inter­ramal papilla is located between the rami on the posterior face (Figure 28b). Each ramus is supported by 2-3 pale embedded acicula extending to the longest part of the acicular lobe. Setae are numerous, long, slender, and capillary, accompanied by 8-10 much shorter furcate setae; each furca has unequally long tines (Figure 28c).

Remarks. Pseudoscalibregma bransfieldia differs from P. parvum (Hansen) from the North Sea. The first has an anterior region of 14 setigers and the second, one of 10-12 setigers. The first has a prostomium with a crest; the crest is absent from the second. There are 31 segments in the first and 36 in the second.”

(Hartman, 1978)