•  
  •  
 

Turkish Journal of Earth Sciences

SACİT ÖZER

DOI

10.3906/yer-0910-28

Abstract

The late Campanian-Maastrichtian transgressive sequences of the southeastern Anatolia (northernmost part of the Arabian platform) and only one Maastrichtian limestone block within the ophiolitic association of the easternmost part of the Taurus Orogenic Belt contain very well-preserved specimens of Dictyoptychus Douvillé 1905. Study of Turkish specimens and also of those described in the literature reveals considerable ontogenic variability, hence need for revision of the species of the genus erected hitherto. Dictyoptychus leesi (Kühn 1929), Dictyoptychus paronai (Kühn 1929), Dictyoptychus persicus (Cox 1934), Dictyoptychus euphratica Karacabey-Öztemür 1979 and Dictyoptychus orontica Karacabey-Öztemür 1979 are accordingly re-interpreted to represent a single species synonymous with Dictyoptychus morgani (Douvillé 1904a). Despite similarities of the canal structure of the right valve of Dictyoptychus striatus (Douvillé 1910) with those of Dictyoptychus morgani (Douvillé 1904a), must remain problematic at present to include in latter species until its very distinctive radial ornamentation and inner margin structure of the right valve is clearly determined. The phyologenetic relations between Dictyoptychus Douvillé 1905, Eodictyoptychus Skelton & El-Asa'ad 1992 and Semailia Morris & Skelton 1995 are investigated. Dictyoptychus quadrizonalis Özer 2005 and Dictyoptychus vanensis Özer 2005 are possibly the most primitive species of the genus. Similarities of the right valve canal structure imply derivation of Dictyoptychus quadrizonalis Özer 2005 from Eodictyoptychus arumaensis Skelton & El-Asa'ad 1992, as well as a possible link between Dictyoptychus morgani (Douvillé 1904), Dictyoptychus vanensis Özer 2005 and Semailia smithi Morris & Skelton 1995. The limited biogeographic distribution of the genus within the Afro-Arabian plate indicates endemism together with Eodictyoptychus Skelton & El-Asa'ad 1992 and Semailia Morris & Skelton 1995.

First Page

583

Last Page

612

Download

Share

COinS