Dasycladalean green algae and some problematic algae from the Upper Triassic of the Nayband Formation (northeast Iran)

Abstract

This paper describes the dasycladales green algae from two sections of the Rhaetian Howz-e Khan Member of the Nayband Formation, northwest of the Dig-e Rostam motorway service area (south of the type locality of the Formation near the town Naybandan). Both sections are composed of bedded fine-grained limestones containing partly abundant dasycladales algae associated with foraminifers, which are mainly aulotortid types. Additionally scattered samples were collected from several beds of the Howz-e Khan Member in this area. The following dasycladalean taxa are described: Chinianella carpatica (Bystrický), Griphoporella curvata (Gümbel), Griphoporella lutensis nov. sp., some undetermined dasycladacean taxa, problematic algae like Lithocodium aggregatum Elliott, Bacinella irregularis Radoicic, and Thaumatoporella parvovesiculifera (Raineri). While Chinianella carpatica is not numerous and the other described algae are rare, Griphoporella curvata is extremely abundant in the investigated material. This paper describes Ch. carpatica for the first time from the Triassic of Iran and also includes a discussion of the strong variability of G. curvata. Additionally we include an informal description of a problematic fossil (animal: shell fragment?; plant: alga?).

Numerical analyses of selected microencrusters from the Cipit boulders of the St Cassian Formation (Dolomites, NE Italy): palaeoecological implications

“… (and references therein); Cherchi & Schroeder ; Senowbari‐Daryan et al . ; Uţa ; Senowbari‐Daryan & Link ]. During the Late Triassic, the diversity of microencrusters and their contribution to the evolution of Triassic reefs increased dramatically.…”

“…The role of microencrusters during the Triassic continued to take more relevance in the Ladinian-Carnian [Flügel et al 2002 (and references therein); Flügel 2010;Sánchez-Beristain & Reitner 2012, 2018Sanchez-Beristain et al 2013;Gale et al 2016Gale et al , 2018], until the Carnian extinction event (Benton et al 2018) and up to the Norian-Rhaetian in the Tehyan realm [e.g. Schäfer 1979;Senowbari-Daryan 1980;Bernecker et al 1999;Flügel et al 2002 (and references therein); Cherchi & Schroeder 2010;Senowbari-Daryan et al 2011;Uţa 2012;Senowbari-Daryan & Link 2018]. During the Late Triassic, the diversity of microencrusters and their contribution to the evolution of Triassic reefs increased dramatically.…”