Dentalina antennula d’Orbigny, 1846

Guðmundsson, Guðmundur, Cedhagen, Tomas & Andersen, Tom, 2022, Taxonomy and distribution of recent species of the subfamily Nodosariinae (Foraminifera) in Icelandic waters, European Journal of Taxonomy 824 (1), pp. 1-74 : 7-9

Dentalina antennula d’Orbigny, 1846

Fig. 2

Dentalina antennula d’Orbigny, 1846: 53 , pl. 2 figs 29–30.

Dentalina antennula – Papp & Schmid 1985: 33, pl. 15 figs 7–9. — Eiland & Guðmundsson 2004: 198, pl. 1 fig. p, pl. 2, fig. c.

Material examined

ICELANDIC WATERS • 1; 64.2689° N, 24.4347° W; RP sledge; depth 213 m; 6.85°C; 35.1 ppt; 3 Sep. 1992; BIOICE 2215 ; IINH 40363 • 3; 63.9169° N, 25.2775° W; RP sledge; depth 240 m; 6.5°C; 35.1 ppt; 3 Sep. 1992; BIOICE 2221 ; IINH 40367 • 1; 63.9269° N, 25.2733° W; detr. sledge (Sneli); depth 242 m; 6.5°C; 35.1 ppt; 3 Sep. 1992; BIOICE 2222 ; IINH 40365 • 1; 63.2503° N, 26.4872° W; RP sledge; depth 1209 m; 4.09°C; 34.94 ppt; 5 Sep. 1992; BIOICE 2257 ; IINH 40366 • 1; 63.1406° N, 24.9908° W; detr. sledge (Sneli); depth 316 m; 6.97°C; 35.12 ppt; 8 Sep. 1992; BIOICE 2272 ; IINH 40364 • 1; 63.9333° N, 10° W; detr. sledge (Sneli); depth 639 m; unknown; unknown; 3 May1993; BIOICE 2321 ; IINH 40270 • 1; 63.75° N, 10.1833° W; RP sledge; depth 555 m; unknown; unknown; 3 May1993; BIOICE 2325 ; IINH 40233 • 5; 63.25° N, 22.2° W; detr. sledge (Sneli); depth 288 m; 6.92°C; 35.1 ppt; 30 Jun. 1993; BIOICE 2392 ; IINH 40271 • 1; 63.2514° N, 22.2033° W; RP sledge; depth 291 m; 6.92°C; 35.1 ppt; 30 Jun. 1993; BIOICE 2393 ; IINH 40361 • 1; 63.175° N, 21.8889° W; RP sledge; depth 346 m; 7.06°C; 35.11 ppt; 30 Jun. 1993; BIOICE 2398 ; IINH 40362 • 2; 63.1306° N, 21.9422° W; detr. sledge (Sneli); depth 511 m; 6.74°C; 35.09 ppt; 1 Jul. 1993; BIOICE 2400 ; IINH 40368 • 3; 63.1278° N, 22.9083° W; RP sledge; depth 520 m; 6.74°C; 35.09 ppt; 1 Jul. 1993; BIOICE 2401 ; IINH 40371 • 1; 63.1778° N, 20.15° W; detr. sledge (Sneli); depth 600 m; 6.46°C; 35.08 ppt; 3 Jul. 1993; BIOICE 2423 ; IINH 40369 • 8; 63.1742° N, 20.165° W; RP sledge; depth 495 m; 6.46°C; 35.08 ppt; 3 Jul. 1993; BIOICE 2424 ; IINH 40372 • 2; 63.0689° N, 19.8592° W; detr. sledge (Sneli); depth 1207 m; 4.45°C; 34.99 ppt; 3 Jul. 1993; BIOICE 2431 ; IINH 40373 • 5; 63.1667° N, 21.525° W; detr. sledge (Sneli); depth 448 m; 6.74°C; 35.09 ppt; 5 Jul. 1993; BIOICE 2468 ; IINH 40370 • 1; 64.575° N, 24.5472° W; RP sledge; depth 273 m; 6.15°C; 35.06 ppt; 6 Sep. 1994; BIOICE 2713 ; IINH 40374 • 1; 64.6833° N, 25.6072° W; detr. sledge (Sneli); depth 212 m; 6.35°C; 35.06 ppt; 22 Aug. 1996; BIOICE 2869 ; IINH 40376 • 1; 64.9225° N, 25.7775° W; Triangle dredge ; depth 183 m; 6.22°C; 35.06 ppt; 30 Aug. 1996; BIOICE 2978 ; IINH 40375 • 1; 62.5206° N, 17.9381° W; Agassiz trawl ; depth 1528 m; 3.57°C; 35.02 ppt; 5 Sep. 2002; BIOICE 3517 ; IINH 40382 • 2; 62.9836° N, 18.1517° W; detr. sledge (Sneli); depth 1232 m; unknown; unknown; 12 Sep. 2002; BIOICE 3546 ; IINH 40378 • 1; 64.1292° N, 24.1047° W; detr. sledge (Sneli); depth 291 m; 7.6°C; 35.18 ppt; 2 Sep. 2003; BIOICE 3549 ; IINH 40379 • 7; 64.1297° N, 24.1044° W; RP sledge; depth 290 m; 7.6°C; 35.18 ppt; 2 Sep. 2003; BIOICE 3550 ; IINH 40381 • 1; 64.2086° N, 26.2211° W; detr. sledge (Sneli); depth 334 m; 6.95°C; 35.14 ppt; 2 Sep. 2003; BIOICE 3557 ; IINH 40380 • 1; 64.2106° N, 26.2117° W; Agassiz trawl; depth 337 m; 6.95°C; 35.14 ppt; 023 Sep. 2003; BIOICE 3559 ; IINH 40377 • 1; 63.32° N, 25.2569° W; detr. sledge (Sneli); depth 296 m; 7.49°C; 35.17 ppt; 11 Sep. 2003; BIOICE 3604 ; IINH 40386 • 2; 63.3289° N, 25.265° W; RP sledge; depth 306 m; 7.49°C; 35.17 ppt; 11 Sep. 2003; BIOICE 3605 ; IINH 40384 • 2; 63.7533° N, 25.7064° W; detr. sledge (Sneli); depth 365 m; 7.1°C; 35.15 ppt; 11 Sep. 2003; BIOICE 3607 ; IINH 40383 • 5; 63.7567° N, 25.7097° W; RP sledge; depth 366 m; 7.1°C; 35.15 ppt; 11 Sep. 2003; BIOICE 3608 ; IINH 40385 .

Description

Test shape elongate, cylindrical, slightly curved to straight, moderately nodular; initial end rounded in megalospheres and only slightly tapering; the microsphere is gradually tapering to a pointed initial end. Length of test 4–5 mm, the largest 7 mm; test width 0.3–0.5 mm. Chambers initially globular to subglobular, becoming slightly more elongated as added; rectilinearly arranged in both generations; number of chambers 5–9 in megalospheres, 15–21 in microspheres. Chamber embracement minimal, sutures horizontal. Aperture radial, nearly central, slightly raised, sometimes protruding, with up to 12 symmetric tines that are fused in the center ( Fig. 2C–D ). Short costae are confined to base of chambers; initial end usually with one or more basal knobs or a short spine. Secondary surface laminations absent (atelo-lamellar). Wall medium thick, finely perforated.

Remarks

Of the 63 examined specimens, 22 were microspheres. Diameter of proloculus in the megalospheres is about 0.5 mm, but less than 0.03 mm in the microsphere. The illustration of the lectotype of D. antennula shows an open, rounded and crenulate aperture, but they also questioned the validity of this species, stating “that the independence of this species remains doubtful” ( Papp & Schmid 1985). Judging from the illustrations it seems that the tip is worn away and it is assumed here that it originally had fused apertural tines as the present specimens. Several names of fossil forms have been erected that seem very similar to D. antennula , like Dentalina capitata ( Boll, 1846) described from the Oligocene by Boll (1846: 177, pl. 2 fig. 13a–b); Dentalina buchi from the Eocene described by Reuss (1851: 60, pl. 3 fig. 6); and Dentalina philippii also from the Eocene and erected by Reuss (1851: 60, pl. 3, fig. 5).

Figures

Fig. 2. Dentalina antennula d’Orbigny, 1846. A, D. Microsphere (BIOICE 2398; IINH 40362) side view (A), and aperture (D). B–C. Megalosphere (BIOICE 2222, IINH 40365), side view (B) and aperture (C), stained with indigo blue. Light source incident light and dark field. Scale bars = 0.25 mm.