Goniatites from the upper viséan shales of county Leitrim, Eire

Abstract

SUMMARYVisean goniatites from rhe rap of the PI Zone are described. Eight new species and one variety are erected. A new genus Hibernicoceras is proposed for the reception of some of these. Observations are made on the genus Prcedaraelites of Schindewolf.

The Early Carboniferous (Mississippian) ammonoids from the Chebket el Hamra (Jerada Basin, Morocco)

“…In conch shape and course of the constrictions, the new material from Chebket el Hamra closely resembles material from the South Portuguese Zone (Fig. 36) and the type specimen of 'Goniatites robustus Moore & Hodson, 1958. However, the suture line of the Irish species has a subacute ventrolateral saddle with strongly converging flanks, whereas in A. proiecturus the ventrolateral saddle is rather broadly rounded.…”

“…warslowensis (Bisat, 1957): with a thickly pachyconic to globular conch (ww/dm ¼ 0.85 at 25 mm dm) and a V-shaped external lobe that is very narrow at its base (0.30-0.35 of external lobe depth), ventrolateral saddle subacute; A. robustus (Moore & Hodson, 1958): with a thickly pachyconic to globular conch (ww/dm ¼ 0.85 at 25 mm dm) and a V-shaped external lobe that is narrow at its base (0.35-0.40 of external lobe depth), ventrolateral saddle subacute; Figure 25. Goniatites globostriatus (Schmidt, 1925).…”

“…It is thus easily separable from the other species. Hibernicoceras Moore & Hodson, 1958 Type species. Hibernicoceras hibernicum Moore & Hodson, 1958. Discussion.…”

“…Hibernicoceras Moore & Hodson, 1958 Type species. Hibernicoceras hibernicum Moore & Hodson, 1958. Discussion. At present, eleven species of Hibernicoceras have been described (AMMON database; Korn & Ilg 2007).…”

“…Two of these, H. mucronatum (Knopp, 1931) and H. waldeckense (Haubold, 1933) are based on crushed, poorly preserved material and are very difficult to interpret. Of the remaining species, only H. hibernicum Moore & Hodson, 1958, H. tumidum Moore & Hodson, 1958, H. striatosphaericum (Brçning, 1923, and H. doliolum Korn, 1988 have been described with respect to their conch ontogeny (Korn 1988(Korn , 1997.…”