Dentalina filiformis (d’Orbigny, 1826)

Fig. 4

Nodosaria (Nodosaire) filiformis d’Orbigny, 1826: 35, no.14.

Dentalina filiformis – Parker et al. 1871: 156, pl. 9 fig. 48. (cit. “Orthocera filiforma aut capillaria” Soldani, Testographia vol. 2, 1798: 35, fig. e). — Jones 1994 (part): 74, pl. 63 fig. 4 (only).

Nodosaria filiformis – Cushman 1913: 55, pl. 27 figs 1–4; 1923: 76–77, pl. 12 figs 1–2.

Laevidentalia filiformis – Eiland & Guðmundsson 2004: 200, pl. 1 fig. b, pl. 3 fig. c.

Material examined

BARENTS SEA • 1; 71.5908° N, 17.7586°E; large Van Veen grab; depth 293 m; 6.4°C; 35.191 ppt; 23 Sep. 2009; MAREANO-2009111 R457-141; IINH 40459.

ICELANDIC WATERS • 1; 63.72° N, 24.4217° W; RP sledge; depth 209 m; 6.98°C; 35.11 ppt; 4 Sep. 1992; BIOICE 2233; IINH 40445 • 1; 63.1514° N, 25.2683° W; RP sledge; depth 546 m; 6.52°C; 35.09 ppt; 8 Sep. 1992; BIOICE 2265; IINH 40419 • 1; 63.7583° N, 22.3528° W; RP sledge; depth 104 m; 7.05°C; 35.03 ppt; 30 Jun. 1993; BIOICE 2385; IINH 40446 • 1; 63.25° N, 22.2° W; detr. sledge (Sneli); depth 288 m; 6.92°C; 35.1 ppt; 30 Jun. 1993; BIOICE 2392; IINH 40420 • 1; 63.2514° N, 22.2033° W; RP sledge; depth 291 m; 6.92°C; 35.1 ppt; 30 Jun. 1993; BIOICE 2393; IINH 40442 • 1; 63.175° N, 21.8889° W; RP sledge; depth 346 m; 7.06°C; 35.11 ppt; 30 Jun. 1993; BIOICE 2398; IINH 40444 • 1; 63.1333° N, 20.6667° W; detr. sledge (Sneli); depth 300 m; 7.02°C; 35.11 ppt; 2 Jul. 1993; BIOICE 2420; IINH 40360 • 1; 63.2611° N, 21.2389° W; RP sledge; depth 180 m; 7.24°C; 35.11 ppt; 5 Jul. 1993; BIOICE 2466; IINH 40449 • 2; 63.1233° N, 21.6119° W; detr. sledge (Sneli); depth 647 m; 6.09°C; 35.06 ppt; 5 Jul. 1993; BIOICE 2471; IINH 40447 • 2; 63.4167° N, 16.8458° W; detr. sledge ( Sneli); depth 277 m; 7.21°C; 35.15 ppt; 25 Aug. 1995; BIOICE 2829; IINH 40451 • 1; 62.8394° N, 18.0117° W; RP sledge; depth 976 m; 3.26°C; 34.98 ppt; 27 Aug. 1995; BIOICE 2849; IINH 40452 • 1; 64.5767° N, 27.6106° W; detr. sledge (Sneli); depth 775 m; 6.05°C; 35.03 ppt; 22 Aug. 1996; BIOICE 2876; IINH 40460 • 3; 65.1722° N, 27.0694° W; RP sledge; depth 229 m; 6.14°C; 35.06 ppt; 23 Aug. 1996; BIOICE 2884; IINH 40450 • 1; 65.1333° N, 23.6° W; Triangle dredge; depth 121 m; 7.97°C; 34.93 ppt; 30 Aug. 1996; BIOICE 2965; IINH 40453 • 1; 63.7667° N, 14.85° W; RP sledge; depth 216 m; 7.67°C; 35.16 ppt; 5 Jul. 1997; BIOICE 2994; IINH 40454 • 1; 63.5747° N, 14.9247° W; Triangle dredge; depth 682 m; 4.73°C; 35.02 ppt; 5 Jul. 1997; BIOICE 3001; IINH 40456 • 1; 64.0397° N, 13.5747° W; RP sledge; depth 135 m; 7.84°C; 35.13 ppt; 9 Jul. 1997; BIOICE 3046; IINH 40455 • 1; 62.7019° N, 25.4619° W; detr. sledge (Sneli); depth 622 m; 7.11°C; 35.14 ppt; 10 Sep. 2003; BIOICE 3600; IINH 40457 • 1; 62.7039° N, 25.4561° W; RP sledge; depth 624 m; 7.11°C; 35.14 ppt; 11 Sep. 2003; BIOICE 3601; IINH 40458

Description

Test shape elongate cylindrical and slender; distinctly curved, slightly nodular, and evenly tapering in a rounded but narrow end. Length of test 2–3 mm, the longest is 4.5 mm; test width 0.15–0.25 mm. Chambers initially cylindrical, becoming slightly inflated and more elongated as added. Chamber arrangement rectilinear, minimal embracement; number of chambers commonly 6–11, or up to 14. Initial chambers in microsphere are rectilinear. Sutures oblique. Aperture radial, nearly central and usually protruding, with up to 16 symmetrically arranged tines that are fused in the center. Surface smooth without ornamentation; secondary surface laminations absent (atelo-lamellar). Wall finely perforated, thin, and transparent.

Remarks

Of the 24 examined specimens, 14 had an intact initial end, with prolocular size that varied nearly continuously from less than 0.05 to about 0.12 mm, presumably including both generations with rectilinear chamber arrangement of the initial part.