Hyalogyrina knorringfjelletensis Nakrem 2017, sp. nov.

• Main Author: Nakrem, Hans Arne
• Format: Other/Unknown Material
• Language: unknown
• Published: Zenodo 2017
• Subjects: Biodiversity; Taxonomy; Animalia; Mollusca; Gastropoda; Hyalogyrinidae; Hyalogyrina; Hyalogyrina knorringfjelletensis; Sassenfjord*; Sassenfjorden; Svalbard; Spitsbergen
• Online Access: https://doi.org/10.5281/zenodo.6009611; http://treatment.plazi.org/id/B5525419D02DFFF9FF7BFA06FC4CF8DD

Hyalogyrina knorringfjelletensis sp. nov. (Fig. 9) 2015 Hyalogyrinidae? gen. et sp. indet.; Hryniewicz et al. 2015a, table 1. Diagnosis. Relatively large low-spired hyalogyrinid with delicate lirate ornamentation on the shell flank. Holotype: PMO 217. 511a, H = 2.6 mm, W = 4.3 mm. Paratype: PMO 217.510, W = 5.2 mm. Type locality and age : Seep #12, Sassenfjorden, Svalbard; late Berriasian (Early Cretaceous). Other material: Two specimens, both illustrated. One from seep #9 (Fig. 9G; PMO 224.763) and one from seep #12 (Fig. 9A, F; PMO 217.508); Sassenfjorden, Svalbard; late Berriasian (Early Cretaceous). Description. Protoconch poorly preserved but apparently hyperstrophic (Fig. 9G, H). Shell turbinateskeneiform, large for the genus. Teleoconch formed of up to four whorls, strongly and evenly convex and ornamented with delicate lirate ornamentation. Growth lines prosocline. Umbilicus and umbilical wall obscured by rock matrix in available specimens. Aperture sub-circular, complete. Remarks. Hyalogyrina knorringfjelleti differs from other similar taxa, both fossil and modern, in having a relatively large size and delicately ornamented shell flanks, recollecting the ornament seen on the umbilical wall of modern hyalogyrinids (Marshall 1988). Hyalogyrina knorringfjelletensis is strongly reminiscent of Alexogyra Bandel, 1996 (synonymized with Bandellina Schröder, 1995 by Kaim 2004) and modern species of Hyalogyrina Marshall, 1988. Distribution : Seeps #9 and #12, Sassenfjorden, Svalbard. Late Berriasian, Early Cretaceous. Etymology : After Knorringfjellet, a mountain above the type locality. Published as part of Nakrem, Hans Arne, 2017, Gastropods from the Late Jurassic - Early Cretaceous seep deposits in Spitsbergen, Svalbard, pp. 351-374 in Zootaxa 4329 (4) on pages 364-365, DOI:10.11646/zootaxa.4329.4.3, http://zenodo.org/record/1003014