Endolobus rota, Korn & Klug, 2023

Korn, Dieter & Klug, Christian, 2023, Early Carboniferous coiled nautiloids from the Anti-Atlas (Morocco), European Journal of Taxonomy 885, pp. 156-194 : 171-172

publication ID	https://doi.org/ 10.5852/ejt.2023.885.2199
publication LSID	lsid:zoobank.org:pub:8432EEFF-391F-4778-81F6-14F3F6ECAA5F
DOI	https://doi.org/10.5281/zenodo.8222760
persistent identifier	https://treatment.plazi.org/id/6E9B29A6-1308-4860-B96A-1C2E1B414621
taxon LSID	lsid:zoobank.org:act:6E9B29A6-1308-4860-B96A-1C2E1B414621
treatment provided by	Felipe
scientific name	Endolobus rota
status	sp. nov.

Treatment

Endolobus rota sp. nov.

urn:lsid:zoobank.org:act:6E9B29A6-1308-4860-B96A-1C2E1B414621

Fig. 11 View Fig ; Table 4 View Table 4

Diagnosis

Species of Endolobus with pachyconic, subinvolute conch (ww/dm ~0.75; uw/dm ~ 0.25), whorl profile moderately compressed (ww/wh ~ 1.60) with slightly flattened venter and broadly rounded ventrolateral shoulder. Coiling rate extremely high (WER ~3.45), whorls not embracing. Ventrolateral shoulder with very low nodes. Suture line with very broad and shallow lobe on the venter and without internal lobe.

Etymology

From the Latin ‘ rota ’, meaning ‘wheel’, because of the conch shape.

Material examined

Holotype MOROCCO • Anti-Atlas, southeast of Gara el Itima , 31.5 km east-northeast of Taouz ; Zrigat Formation; Korn & Ebbighausen 2007 Coll.; illustrated in Fig. 11 View Fig ; MB.C.31289 .

Description

Specimen MB.C.31289 is a fragment of a specimen with about 85 mm conch diameter, consisting of three chambers and a short part of the body chamber with about 63 mm whorl width ( Fig. 11A View Fig ). At a whorl height of 39 mm, it has a ww/wh ratio of 1.60, but this ratio increases markedly during the previous half volution. The whorl profile is rounded-triangular with a broad venter, a broadly rounded ventrolateral shoulder and a nearly semicircular area consisting of flanks and dorsum ( Fig. 11A View Fig ). A concave dorsal whorl zone does not exist. One large and very low ventrolateral node is visible on the fragment. The suture line extends with a wide and shallow lobe across the venter; it forms a low saddle on the flank and does not possess an internal lobe ( Fig. 11B View Fig ).

Remarks

Endolobus rota differs from the other Early Carboniferous species of the genus mainly in the very low and broad nodes on the ventrolateral margin. Another criterion is the lack of whorl overlap, but this may be due to the relatively small size of the holotype when compared with the North American species of Endolobus .