On <i>Lithocodium</i> Elliott (Calcareous algae); its paleobiological and stratigraphical significance

Abstract

Abstract. Lithocodium aggregatum Elliott (with its synonyms, Bacinella irregularis Radoiĉić and Pseudolithocodium carpaticum Miŝík), Radoicicinellopsis sterni (Radoiĉić) and Bacinellacodium calcareus Dragastan are referred to the new subfamily Lithocodioidea of the family Codiaceae (marine, chlorophycean, calcareous algae). The significance which has been ascribed to these taxa by past authors is assessed. Radoicicinellopsis is proposed as a new genus. Lithocodium is redescribed and its diagnosis is emended. The importance of this alga in palaeoenvironmental interpretation and fossil hydrocarbon accumulation is noted.

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

“…They were also described as a single organism by some authors or as separate genus/species by others (for more information see Banner et al 1990;Schlagintweit et al 2010). Bacinella and Lithocodium were not found in association in the investigated material.…”

“…Lithocodium aggregatum was attributed to luftusiid foraminifer by Schmid & Leinfelder (1996). Banner et al (1990) synonymized Bacinella irregularis Radoicic (1959) and Pseudolithocodium carpaticum Mišík (1979) with Lithocodium, attributing these to the new subfamily Lithocodioidea within the family Codiaceae (Siphonales, Clorophyceae). For Bacinella?…”

“…For Bacinella? sterni Radoicic (1972) the new genus Radoicicinellopis was established by Banner et al (1990). Cherchi & Schroeder (2006) favour, that Lithocodium is a calcified cyanobacterium rather than a foraminifer.…”

“…Recently Schlagintweit et al (2010) discussed the systematic position of Lithocodium attributing it to "filamentous-septate heterotrichale ulvophycean alga". Assigning to "endolithic ulvophycean alga" these authors separate Bacinella from Lithocodium, which was synonymized by Banner et al (1990). With separation of Lithocodium and Bacinella the systematic classification proposed by Schlagintweit et al (2010) is followed here to describe the two following organisms.…”

“…It is characterized by hollow cavities covered by a layer with thin-walled alveoli. A detailed description of Lithocodium and discussion about its systematic position are given by Banner et al (1990), Schmid & Leinfelder (1995, 1996, Cherchi & Schroeder (2006), and by Schlagintweit et al (2010).…”