Globularia Swainson, 1840

Hryniewicz, Krzysztof, Amano, Kazutaka, Bitner, Maria Aleksandra, Hagström, Jonas, Kiel, Steffen, Klompmaker, Adiël A., Mörs, Thomas, Robins, Cristina M. & Kaim, Andrzej, 2019, A late Paleocene fauna from shallow-water chemosynthesis-based ecosystems, Spitsbergen, Svalbard, Acta Palaeontologica Polonica 64 (1), pp. 101-141 : 107

Genus Globularia Swainson, 1840

Type species: Ampullaria sigaretina Lamarck, 1804 ; Eocene , France .

Globularia isfjordensis ( Vonderbank, 1970)

Fig. 5 .

1925 Natica spec. 1 ; Hägg 1925: 45, pl. 3: 2.

1925 Natica spec. 2 ; Hägg 1925: 45, pl. 3: 3.

1925 Natica spec. 3 ; Hägg 1925: 45, pl. 3: 4.

1927 Natica sp. ; Gripp 1927: 32, pl. 6: 11.

1970 Ampullonatica isfjordensis n. sp.; Vonderbank 1970: 87, pl. 8: 1–6.

2016 “Naticiform” gastropod sp.; Hryniewicz et al. 2016: table 1, fig. 12G.

Material.—Ten specimens, poorly to immoderately well preserved shells, including the holotype ( GPIBo 111) from Vonderbank’s (1970) collection (four figured GPIBo 110– 113) and four specimens from Hägg’s (1925) collection (one figured NRM-PZ Mo 149179); from the upper Paleocene, Basilika Formation, Fossildalen, locality 500 m from Hollendarbukta, Spitsbergen, Svalbard.

Measurements.—The holotype ( GPIBo 111): H, 12.5 mm; W, 10.5 mm. NRM-PZ Mo 149179: H, 22 mm; W, 19 mm.

Original diagnosis (from Vonderbank 1970).—Eine Art der Gattung Ampullonatica mit flach eingesenkten Nähten, schwach bogenförmigen Parietalrand und ± offenem Nabel. [A species of the genus Ampullonatica with weakly incised sutures, slightly arched parietal margin and ± open umbilicus].

Description. —Protoconch and juvenile teleoconch not preserved. Shell naticiform, thin-shelled with strongly inflated whorls and moderately incised suture. Ornamentation absent apart from enhanced, orthocline to slightly sinusoidal growth lines. Aperture poorly preserved in all available specimens. No umbilicus observed, contrary to statement by Vonderbank (1970). Parietal callus not developed and no other apertural elaborations preserved.

Remarks.— Vonderbank (1970) classified his new species in the naticid genus Ampullonatica Sacco, 1890a , which is invalid due to its type species being a nomen nudum. In an older account, Hägg (1925) divided the naticiform gastropods from Isfjorden into three species of Natica Scopoli, 1777 in open nomenclature, but provided no description of the species in question. Gripp (1927) also left this form as a species of Natica in open nomenclature, but compared it to a number of naticiform species currently classified as representatives of Ampullinidae (e.g., Ampullospira Harris, 1897 , Crommium Cossmann, 1888 , Amauropsella Bayle in Chelot, 1885, Euspirocrommium Sacco, 1890b , and Amauropsis Mörch, 1857 ). We also think that this form is more similar to ampullinids rather than to naticids due to the thin shell, absence of an umbilicus and parietal callus and enhanced growth lines. On the other hand, in molluscan fossils from the studied collection, we noticed several drill holes that could be attributed to predatory gastropods (such as naticids), although another species of predatory gastropod not yet found in Basilika Formation could have been responsible for these holes. Drill holes have been noted previously in fossil cold seep mollusks ( Amano 2003; Amano and Jenkins 2007; Amano and Kiel 2007; Kiel et al. 2008, 2016). The species identified by Hägg (1925) as Nassa sp. ( Fig. 4C ) most likely is a poorly preserved aporrhaid (see above).

Stratigraphic and geographic range.—Upper Paleocene cold seep carbonates from the Basilika Formation, Fossildalen and locality 500 m west of Trigonometric point 25, Hollendarbukta, Spitsbergen, Svalbard.

Figures

Fig.5.Ampullinidgastropod Globulariaisfjordensis (Vonderbank,1970) from theupper Paleocene,Basilika Formation,locality 500 mfrom Trigonometric point 25, Hollendarbukta (A–D) and Fossildalen (E), Spitsbergen, Svalbard. A. GPIBo 111 (holotype). B. GPIBo 112. C. GPIBo 113. D. GPIBo 110. E. NRM-PZ Mo 149179. Apertural (A1, B1, C1, D1. E1), lateral (A2, B2, C2, D2, E2), and apical (A3, B3) views.

Fig.4.Aporrhaid and scaphandrid gastropods from the upper Paleocene, Basilika Formation, locality 500 m west from Trigonometric point 25, Hollendarbukta (A, B, D) and Fossildalen (C), Spitsbergen, Svalbard. A, B. Aporrhais cf. gracilis Koenen, 1885, GPIBo 117 (A) and GPIBo 116 (B) in lateral (A1, B1) and apical (A2, B2) views.C.?Aporrhais cf.gracilis Koenen, 1885, identified by Hägg (1925) as Nassa sp., NRM-PZ Mo 149182 in apical (C1), lateral C2) and latero-apertural (C3) views. D. Ellipsoscapha sp. GPIBo 115 in apertural (D1), lateral (D2), apical (D3), and abapical (D4) views.