Acervulina Schultze 1854

Mamo, Briony L., 2016, Benthic Foraminifera from the Capricorn Group, Great Barrier Reef, Australia, Zootaxa 4215 (1), pp. 1-123 : 94

Acervulina Schultze 1854

Acervulina mabahethi ( Said 1949) ( Fig. 22 :18–20; 23:1–3)

1949 Planorbulina mabahethi Said , p. 44, pl. 4, fig. 26.

1993 Acervulina mabahethi (Said) ; Hottinger et al., p. 122, pl. 165, figs 1–7; pl. 166, figs 1–8. 1994 Planorbulina mabahethi Said ; Loeblich & Tappan, p. 152, pl. 323, figs 11–13. 1997 Acervulina mabahethi (Said) ; Haig, p. 275, fig. 5: 26.

2009 Acervulina mabahethi (Said) ; Parker, p. 475, figs 341a–i, 342a–j, 343a– i. 2012 Acervulina mabahethi (Said) ; Debenay, p. 234, pl. 22.

Description. See Hottinger et al. (1993, p. 122, pl. 165, figs 1–7; pl. 166, figs 1–8) and Parker (2009, p. 475, figs 341a–i, 342a–j, 343a–i).

Remarks. Acervulina mabahethi ( Said 1949) has flat, irregularly arranged rounded chambers that are added on a single plane and bear a coarsely perforate ornament. The numerous small sutural apertures are elliptical to circular in shape and have thickened peristomal lips ( Fig. 22 :18–20; 23:1–3).

As illustrated by Hottinger et al. (1993, pl. 165, figs 1–7; pl. 166, figs 1–8) and Parker (2009, figs 341a–i, 342a–j, 343a–i), A. mabahethi exhibits a broad spectrum of morphotypes, the result of the underlying substrate influencing test shape and chamber arrangement. Some specimens have closely spaced perforations whilst others are widely spaced and other specimens bear a pustulose ornament on the ventral side of the test. Specimens from the CG also vary greatly in test shape and aperture style with crescent or circular shapes dominant ( Fig. 22 :18–20; 23:1–3).

Said (1949) originally collected A. mabahethi from the Red Sea and Hottinger et al. (1993) provided an extensive description of specimens from the Gulf of Aqaba and the Red Sea . This species has a global distribution (Timor Sea from 27 m—Loeblich & Tappan 1994; Exmouth Gulf—Haig 1997; Ningaloo Reef—Parker 2009; New Caledonia to 100 m—Debenay 2012).

Distribution within study area. Acervulina mabahethi occurs in low abundance (only one to four specimens per site), but was absent from Sykes Reef, the channel samples and was only found once within Wistari Reef. The site of greatest abundance was the relatively shallow site 50 at the southern end of One Tree Lagoon 2. Acervulina mabahethi was most frequently collected along the ST/HW transect across the southern face of Heron Reef flat.

Figures

FIGURE 22. (Unless otherwise specified all scale bars = 100 µm). 1 – 4. Cymbaloporetta sp. 1. 1 – 2. QM # G 465969 from OTI 45 peripheral (1) and umbilical (2) views. 3 – 4. QM # G 465971 from OTI 48 peripheral (3) and umbilical (4) views. 5 – 6. Cymbaloporetta? sp. 1, QM # G 466024 from T 1 – 4. Spiral view (5) and close-up spiral view (6). Scale bar for 5 = 200 µm. Scale bar for 6 = 20 µm. 7 – 17. Millettiana milletti (Heron-Allen & Earland, 1915). 7. QM # G 465789 from ST / HW 2, spiral view. 8 – 9. QM # G 465788 from ST / HW 2, peripheral (8) and umbilical (9) views. 10 – 12. QM # G 466032 from ST / HW 8, spiral (10) close-up spiral (11) and peripheral (12) views. Scale bar for 10 = 200 µm. Scale bar for 11 = 50 µm. Scale bar for 12 = 20 µm. 13 – 14. QM # G 466027 from T 1 – 2 spiral (13) and peripheral (14) views. Scale bar for 14 = 50 µm. 15. QM # G 466140 from OTI 50, umbilical view. Scale bar = 50 µm. 16 – 17. QM # G 466088 from OTI 50 spiral (16) and peripheral (17) views. Scale bar for 17 = 50 µm. 1 8 – 20. Acervulina mabahethi (Said, 1949). 18 – 20. QM # G 466003 from OTI 53 spiral (7), umbilical (8) and peripheral (20) views.