Hyalopomatus marenzelleri Langerhans 1884

Hyalopomatus marenzelleri Langerhans, 1884

Hyalopomatus marenzelleri Langerhans, 1884, p. 278, pl. 17: fig. 49, a–d.—Ehlers, 1887, p. 307.—Knox, 1959, p. 111.

Hyalopomatopsis marenzelleri.—Saint-Joseph, 1894, pp. 224, 261.—Fauvel, 1909, p. 59; 1911b, p. 39; 1914, p. 341; 1932, p. 39.—Hartman, 1948, p. 48; 1959, p. 577.—Southward, 1963, pp. 578–580, fig. 4, A-J—Zibrowius, 1968a, p. 177; 1968b, pp. 385–386. 387, figs. 19–23.

MATERIAL EXAMINED.—Madeira: 4 spec., empty tubes, French “Jean Charcot” expedition, several stations, 1966. Southern Portugal: several spec. and tubes on corals, French-Portuguese “Faial” Expedition, sta. P. 59, 1957. Josephine Bank: empty tubes, Swedish “Skagerak” Expedition, station of 31 May 1946 (NMG).

DESCRIPTION.—Tube white, round and smooth, without keels, diameter about 500 μ. Part attached to the substratum sometimes with some transverse peristomes slightly widened out. Total length of the animal about 11 mm, more than a third for the gill tuft. Up to 45 abdominal segments. Collar trilobed, short thoracic membranes ending at the posterior limit of segment 2. Gill tuft composed of about 7 filaments on each side, first dorsal filament on the left side non-pinnate, transformed into a very thin opercular peduncle. Operculum a vesicle of globular or slightly oval shape, with a distal, slightly convex, slightly differentiated horny cap. First thoracic setigerous segment with capillary setae and special setae, the latter with a distal limbate zone and a distinct but not well separated proximal wing of stronger teeth. Segments 2 to 7 with limbate and capillary setae. No thoracic sickle-setae. Distal part of the abdominal setae (about one-tenth of their length) geniculate. Thoracic uncini rasp-shaped with the anterior tooth bifurcate; when seen in profile with about 20 teeth. Abdominal uncini of smaller size but similar.

DISTRIBUTION.—Hyalopomatus marenzelleri is known from a large zone in the temperate North Atlantic comprising the Azores, Madeira, and the Gulf of Biscay. It is common in bathyal depths, whereas its records from depths of only 100–200 m

are less frequent: Azores (845–1850 m), Madeira (100–2800 m), Josephine Bank (208–225 m), southern Portugal (38°16′8″N, 8°56′43″W, about 300 m), continental slope off Brittany and Scilly Islands (366–1630 m).