Pectinodonta borealis Nakrem 2017, sp. nov. ...

? Pectinodonta borealis sp. nov. (Fig. 3D–H) 2015 Acmaeidae gen. et sp. indet.; Hryniewicz et al. 2015a, table 1. Diagnosis: Surface covered with thick commarginal ribs. Aperture elongated, oval. Apex slightly subcentral. Holotype: PMO 217.516, H = 1.8 mm, L = 4.1 mm, W = 3.3 mm. Type locality and a...

Full description

Bibliographic Details
Main Author: Nakrem, Hans Arne
Format: Text
Language:unknown
Published: Zenodo 2017
Subjects:
Online Access:https://dx.doi.org/10.5281/zenodo.6009541
https://zenodo.org/doi/10.5281/zenodo.6009541
Description
Summary:? Pectinodonta borealis sp. nov. (Fig. 3D–H) 2015 Acmaeidae gen. et sp. indet.; Hryniewicz et al. 2015a, table 1. Diagnosis: Surface covered with thick commarginal ribs. Aperture elongated, oval. Apex slightly subcentral. Holotype: PMO 217.516, H = 1.8 mm, L = 4.1 mm, W = 3.3 mm. Type locality and age: Seep #9, Sassenfjorden, Svalbard; late Berriasian, Early Cretaceous. Other material: Two additional specimens (one illustrated PMO 224.752) from the type locality. Description. Protoconch not preserved. Shell patelliform, elongate, oval; width is 81% of length. Apex moderately high, heavily eroded, situated slightly subcentrally; height is 43% of length. Shell exterior covered with thick concentric ribs. Radial ornament very weak, consisting of straight and faint radial riblets. Apertural margin straight in lateral view. Muscle scars not visible. Remarks. The concept of genera in Pectinodontidae is based mainly on radular characters (Sasaki et al. 2003). A slight difference in the apex position delimits, ... : 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 354-355, DOI: 10.11646/zootaxa.4329.4.3, http://zenodo.org/record/1003014 ...