Naineris furcillata

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 : 97-98

Naineris furcillata new name

Figure 45

Naineris chilensis Carrasco, 1977: 70 –72, figs. 5–6, homonym of N. dendritica chilensis Hartmann-Schröder, 1965 ; Rozbaczylo 1985: 130.

Material examined. Argentina, Staten Island off Tierra del Fuego, Hero Cruise 712, Sta. 664 (1, USNM 60639 ) . — Strait of Magellan, Eltanin Cruise 11, Sta. 960 (1, USNM 60638 ) .

Description. Both specimens posteriorly incomplete, with largest (USNM 60639) 23 mm long, 2 mm wide for 64 setigers. Color in alcohol: light tan to brown.

Prostomium blunt, with slightly rounded frontal margin ( Fig. 45 A); no eyespots; peristomium a simple achaetous ring, ventrally forming lips of mouth; proboscis partially everted, appearing dendritic. Thoracic region with 17–19 setigers, appearing dorsally compressed; 1–2 transitional segments present between thorax and abdomen; abdominal region cylindrical.

Branchiae from setiger 4, continuing to posterior end; each branchia flattened, cirriform, tapering to pointed tip ( Fig. 45 F–G), ciliated on inner margins; branchiae of posterior segments flatter and broader ( Fig. 45 H).

Thoracic notopodial postsetal lobe elongate, thin, and fingerlike, with forked tips by setiger 17–18 ( Fig. 45 G); subsequent notopodial lobes and those of posterior segments forked ( Fig. 45 H) or undivided; occurrence of forked notopodial lobes irregular from segment to segment; interramal cirrus absent. Thoracic neuropodia slightly thickened, with short, fingerlike postsetal lobe from setiger 1 ( Fig. 45 F); abdominal neuropodia divided into two apical lobes, between which setae emerge ( Fig. 45 H).

Thoracic notopodia with 30–40 long, crenulated capillaries and 3–5 furcate setae; abdominal notopodia with few capillaries and furcate setae; each furcate seta with unequal tynes having blunted, bifid tips; tynes connected by a thin membrane composed of very fine needles, shafts with transverse ribs ( Fig. 45 E).Thoracic neuropodia with dense fascicles of uncini ( Fig. 45 B) and crenulated capillaries ( Fig. 45 C); each uncinus with transverse ribs; abdominal neurosetae reduced to a few crenulated capillaries and 1–2 smooth, slightly curved aciculae ( Fig. 45 D).

Etymology. furcillata: Latin for forked.

Remarks. Naineris chilensis Carrasco, 1977 is a junior homonym of N. dendritica chilensis Hartmann- Schröder , 1965 and is herein renamed N. furcillata . The specimens described here are considered to represent the same species as Carrasco’s material from western Chile. The type specimens of Carrasco’s species were requested but were not provided. Naineris furcillata is unique in the genus in having the posterior thoracic and abdominal notopodial postsetal lobes and abdominal neuropodia with bifid or forked tips. The occurrence of forked or undivided lobes in the notopodia is variable from segment to segment, but consistent in the neuropodia; Carrasco’s holotype is depicted as having only the neuropodial lobes forked.

Distribution. Argentina, Patagonian region; Chile, Strait of Magellan; 10– 64 m.

Figures

FIGURE 45. Naineris furcillata n. nom. (USNM 60639). — A, anterior end, dorsal view; B, thoracic neuropodial uncinus; C, thoracic neuropodial capillary; D, abdominal neuropodial acicula; E, furcate seta; F, anterior thoracic parapodium, anterior view; G, posterior thoracic parapodium, posterior view; H, abdominal parapodium, posterior view.