Grigelis semirugosus? ( d’Orbigny, 1846 ) (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 : 35-36

Grigelis semirugosus? ( d’Orbigny, 1846)

Fig. 9

Nodosaria semirugosa d’Orbigny, 1846: 34 , pl. 1 figs 20–23 (rugosa in plate text).

Grigelis semirugosa – Jones 1994: 75, pl. 63 figs 23–27.

non Nodosaria pyrula ( d’Orbigny, 1826) – Papp & Schmid 1985: 24 (nr. 10), pl. 4 figs 6–8.

Material examined

ICELANDIC WATERS • 5; 66.3425° N, 23.5217° W; RP sledge; depth 158 m; 6.66°C; 35.06 ppt; 25 Jul. 2004; BIOICE 3669 ; IINH 40403 • 1; 63.2556° N, 21.2389° W; detr. sledge (Sneli); depth 180 m; 7.24°C; 35.11 ppt; 5 Jul. 1993; BIOICE 2465 ; IINH 40402 .

Description

Test shape elongate, nearly straight to slightly curved, strongly nodular, barely tapering, or successive chambers are of equal diameter. Length of test fragments 2–3 mm, comprising 3–7 chambers; test width 0.2–0.3 mm. Chambers pear-shaped with an elongated long neck, rectilinearly arranged, with minimal embracement; chambers attached at the very end of the apertural neck; number of chambers unknown, the largest fragment has 7 chambers. Sutures horizontal. Aperture radial, protruding and central, at the end of a long neck; radial tines up to 12, symmetrically arranged and fused in the center. Longitudinal striae cover the apertural neck and the upper and lower part of the chambers, leaving the central part smooth. Secondary surface laminations absent, wall finely perforated thin and transparent.

Remarks

Typical G. semirugosus ? has distinct costae or furrows that are mostly confined to the base of the chambers. However, the six specimen fragments at hand differ in having rather faint striations or furrows, covering the upper half and the lower part of the chambers, leaving the central part smooth ( Fig. 9A ). In addition to being striated, the putative P. semirugosus ? differs from P. pyrula in having a relatively shorter and more conical neck. The initial end in available material is missing.

Figures

Fig. 9. Grigelis semirugosus? (d’Orbigny, 1846). A. Specimen with missing initial end (BIOICE 3669, IINH 40403). B. Detail of aperture (BIOICE 2465, IINH 40402). Light source combination of incident light and dark field. Scale bars = 0.25 mm.