Eocanites brevis
Creators: name: Korn, Dieter
name: Weyer, Dieter
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Animalia
Mollusca
Cephalopoda
Prolecanitida
Prolecanitidae
Eocanites
Eocanites brevis

description: Eocanites brevis (Vöhringer, 1960)
Figs 121–122; Tables 115–116
Protocanites supradevonicus brevis Vöhringer, 1960: 172, pl. 6 fig. 5, text-fig. 46a.
Protocanites (Eocanites) supradevonicus brevis – Weyer 1965: 458, pl. 6 fig. 5.
Eocanites brevis – Korn 1994: 81, text-figs 73c, 75b. — Korn et al. 2003b: 1125, text-fig. 3a.
Diagnosis
Species of the genus Eocanites with a conch reaching 50 mm diameter. Conch at 12 mm dm evolute (uw/dm ~0.50) with weakly compressed whorl profile (ww/wh ~0.90) and broadly rounded venter; conch at 30 mm dm evolute (uw/dm ~0.50) with weakly compressed whorl profile (ww/wh ~0.85) and broadly rounded venter. Ornament with coarse, strongly rursiradiate, concavo-convex growth lines with moderately deep ventral sinus; without ribs.
Material examined
Holotype
GERMANY • Rhenish Mountains, Oberrödinghausen, railway cutting; Hangenberg Limestone, bed 3c; Vöhringer Coll.; illustrated by Vöhringer (1960: pl. 6 fig. 5) and Korn (1994, text-fig. 73c); re-illustrated here in Fig. 121A; GPIT-PV- 63985.
Paratypes
GERMANY • 1 specimen; Rhenish Mountains, Oberrödinghausen, railway cutting; Hangenberg Limestone,bed3a;Vöhringer Coll.;GPIT-PV-63983 • 1specimen;Rhenish Mountains,Oberrödinghausen, railway cutting; Hangenberg Limestone, bed 3c; Vöhringer Coll.; GPIT-PV-63987.
Additional material
GERMANY • 1 specimen; Rhenish Mountains, Oberrödinghausen, railway cutting; Hangenberg Limestone, loose material; Korn 1990 Coll.; MB.C. 31236 • 5 specimens; Rhenish Mountains, Oberrödinghausen, railway cutting; Hangenberg Limestone, bed 3a; Weyer 1993–1994 Coll.; MB.C. 31237.3–5 • 1 specimen; Rhenish Mountains, Oberrödinghausen, railway cutting; Hangenberg Limestone, bed 3c 1; Weyer 1993–1994 Coll.; MB.C. 31238 • 3 specimens; Rhenish Mountains, Oberrödinghausen, railway cutting; Hangenberg Limestone, bed 3d1; Weyer 1993–1994 Coll.; MB.C. 31239.1–3.
Description
Holotype GPIT-PV-63985 is a completely shell-covered specimen of 18 mm conch diameter (Fig. 121A). It is extremely discoidal and evolute (ww/dm ~0.22; uw/dm ~0.50) with a compressed oval whorl profile (ww/wh ~0.80). The ornament consists of rather coarse growth lines, which are directed backwards on the inner flank half and describe a radial course on the outer flank half; the ventral sinus is rather shallow and broadly rounded (Fig. 122B).
The cross section of paratype GPIT-PV-63987 allows the study of the conch ontogeny from the initial stage to a diameter of 27 mm (Fig. 122A). All stages larger than 2 mm dm are very similar in shape with almost static umbilical width and coiling rate (Fig. 122C, E); however, the whorl profile becomes continuously narrower (from ww/wh ~1.50 at 2 mm dm to ~0.85 at 27 mm dm; (Fig. 122D).
Remarks
Eocanites brevis resembles E. nodosus, but has considerably weaker growth lines and no spiral lines. Eocanites brevis is separated from E. delicatus sp. nov. by the compressed whorl profile (ww/wh ~ 0.80 in E. brevis but ~ 0.90 in E. delicatus at about 40 mm dm) and from E. planus by the wider umbilicus (uw/dm ~ 0.50 in contrast to less than 0.45 in E. planus).
description: Published as part of Korn, Dieter & Weyer, Dieter, 2023, The ammonoids from the Gattendorfia Limestone of Oberrödinghausen (Early Carboniferous; Rhenish Mountains, Germany), pp. 1-230 in European Journal of Taxonomy 882 on pages 199-201, DOI: 10.5852/ejt.2023.882.2177, http://zenodo.org/record/8177581