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Image of <i>Laonice weddellia</i> Hartman 1978
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Laonice weddellia Hartman 1978

Description

provided by NMNH Antarctic Invertebrates

Laonice weddellia n. sp.
Figs. 16 a-16 c

Material. Weddell Sea, in 400-659 m: Station 68­5 (2 specimens); 68-9 (1 specimen) ; 69-1 (3 frag­ments) ; 69-2 (5 specimens) ; 69-6 (3 specimens) ; 69-7 (15 specimens) ; 69-8 (holotype and 20 paratypes); 69-10 (3 specimens). Hero Inlet, in 40 m (9 speci­mens).

Description. One of the largest specimens, from station 69-10 (USNM 46709), is damaged in the cephalic region. It measures 31 mm long and 1.2 mm wide and consists of 67 segments. The types (USNM 46700-1) measure 12-15 mm long for 33 segments. Transverse dorsal ciliated ridges occur along the intersegmental grooves, becoming more distinct in the posterior half of the body. The prostomium is longer than it is wide (slightly wider anteriorly) and has four eyes in trapezoidal arrangement. The anterior eyes are minute, and the posterior ones are much larger and are reddish. A small erect antenna is located on the posterior end of the lobe. A con­spicuous sensory middorsal ridge extends back through setiger 12.

Branchiae are cirriform, first present on setiger 2 (at first small), increasing in size posteriorly; the largest branchiae are between setigers 10 and 30. They continue posteriorly to setigers 21-50 and irregularly thereafter to setiger 56; a long posterior region lacks branchiae. In postmedian segments the branchiae are densely ciliated along their outer margins (Figure 16a).

Interramal pouches first appear between setigers 9 and 10, rarely between setigers 8 and 9; they are well developed through a long region and absent from 25 or more posterior segments.

Anterior parapodia have only long simple smooth distally pointed setae in notopodia and neuropodia. Neuropodial uncini (Figure 16b) first appear in setiger 21, near the end of the branchial region; there are 5-8 in a row, alternating with more slender capillary setae. The inferiormost neuroseta is thicker, punctate, and slightly curved. Posteriormost notopodia lack hooded uncini.

A tapering posterior end measures 8 mm long for 28 segments. The last segment is setigerous. The pygidium tapers and is bounded by a circlet of seven cirriform processes, the midventral one being thicker; the anal pore is centered (Figure 16c).

Remarks. Laonice weddellia differs from L. cir­rata (Sars) in the following ways: Interramal pouches are first present from setigers 8-9 or 9-10 in the first and from setigers 25-26 in the second. Neuropodial uncini are present from setiger 21 in the first and from setiger 40-50 in the second; the mid-dorsal sensory groove extends back to setiger 12 in the first and to setigers 28-30 in the second. Laonice weddellia differs from subspecies of L. cirrata (L. cirrata praecirrata and L. cirrata postcirrata), named from Chile by Hartmann-Schroder [1965, pp. 206-2071, in that the two subspecies lack interramal pouches.

Etymology. The species is named for its origin in the Weddell Sea.”

(Hartman, 1978)

Depth range

provided by World Register of Marine Species
40 m (Hero Inlet, Antarctica); 400-659 m (Weddell Sea, Antarctica).
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cc-by-4.0
copyright
WoRMS Editorial Board
bibliographic citation
Hartman, O. (1978). Polychaeta from the Weddell Sea quadrant, Antarctica. <em>Antarctic Research Series.</em> 26(4): 125-223. Fauchald, K. (2007). World Register of Polychaeta. Hartman, O. (1978). Polychaeta from the Weddell Sea quadrant, Antarctica. <em>Antarctic Research Series.</em> 26(4): 125-223. Hartman, O. (1978). Polychaeta from the Weddell Sea quadrant, Antarctica. <em>Antarctic Research Series.</em> 26(4): 125-223. Hartman, O. (1978). Polychaeta from the Weddell Sea quadrant, Antarctica. <em>Antarctic Research Series.</em> 26(4): 125-223. Hartman, O. (1978). Polychaeta from the Weddell Sea quadrant, Antarctica. <em>Antarctic Research Series.</em> 26(4): 125-223.
i18n: Contributor
João Gil [email]

Distribution

provided by World Register of Marine Species
Antarctic Ocean, at the Weddell Sea.
license
cc-by-4.0
copyright
WoRMS Editorial Board
bibliographic citation
Hartman, O. (1978). Polychaeta from the Weddell Sea quadrant, Antarctica. <em>Antarctic Research Series.</em> 26(4): 125-223. Fauchald, K. (2007). World Register of Polychaeta. Hartman, O. (1978). Polychaeta from the Weddell Sea quadrant, Antarctica. <em>Antarctic Research Series.</em> 26(4): 125-223. Hartman, O. (1978). Polychaeta from the Weddell Sea quadrant, Antarctica. <em>Antarctic Research Series.</em> 26(4): 125-223. Hartman, O. (1978). Polychaeta from the Weddell Sea quadrant, Antarctica. <em>Antarctic Research Series.</em> 26(4): 125-223. Hartman, O. (1978). Polychaeta from the Weddell Sea quadrant, Antarctica. <em>Antarctic Research Series.</em> 26(4): 125-223.
i18n: Contributor
João Gil [email]

Habitat

provided by World Register of Marine Species
Not stated. Occurs at bathyal depths.
license
cc-by-4.0
copyright
WoRMS Editorial Board
bibliographic citation
Hartman, O. (1978). Polychaeta from the Weddell Sea quadrant, Antarctica. <em>Antarctic Research Series.</em> 26(4): 125-223. Fauchald, K. (2007). World Register of Polychaeta. Hartman, O. (1978). Polychaeta from the Weddell Sea quadrant, Antarctica. <em>Antarctic Research Series.</em> 26(4): 125-223. Hartman, O. (1978). Polychaeta from the Weddell Sea quadrant, Antarctica. <em>Antarctic Research Series.</em> 26(4): 125-223. Hartman, O. (1978). Polychaeta from the Weddell Sea quadrant, Antarctica. <em>Antarctic Research Series.</em> 26(4): 125-223. Hartman, O. (1978). Polychaeta from the Weddell Sea quadrant, Antarctica. <em>Antarctic Research Series.</em> 26(4): 125-223.
i18n: Contributor
João Gil [email]