The Enigmatic Avian Oogenus Psammornis: A Review of Stratigraphic Evidence

Abstract

Psammornis rothschildi is an avian taxon established by Andrews in 1911 on the basis of eggshell fragments surface-collected near the city of Touggourt, in the north-eastern part of the Algerian Sahara. Since the initial discovery, a number of Psammornis specimens have been reported from various localities in North Africa (Algeria, Tunisia, Libya, Mauritania) and the Middle East (Saudi Arabia, Iran). Most of the finds lack a stratigraphic context, which has resulted in considerable confusion about the geological age of Psammornis, with attributions ranging from the Eocene to the Holocene. A review of the available evidence shows that only two groups of localities provide reasonably reliable stratigraphic evidence: the Segui Formation of SW Tunisia, apparently of latest Miocene age, and the Aguerguerian (Middle Pleistocene) of NW Mauritania. This suggests a fairly long time range for Psammornis. Psammornis eggs are, in all likelihood, those of giant ostriches, although the lack of associated skeletal material makes it difficult to interpret the eggshell fragments in evolutionary terms. However, the oological record suggests that giant ostriches have been present in Africa since the late Miocene, which leads to the reconsideration of some hypotheses about the palaeobiogeographical history of the Struthionidae. The lack of Psammornis eggs transformed by humans suggests that this giant ostrich did not survive until Epipalaeolthic or Neolithic times.

Correlación de la Formación Marsawdad, Omán, Mioceno Superior (Turoliense-Ventiense), basada en las de cáscaras fósiles de huevos avianos

“…The base of the succession is reported to be an iron-stained calcrete or a brown limestone palaeosol which locally has a travertine-like aspect. Berthiaux et al 1992;Chevrel et al 1992;Platel & Berthiaux, 1992a, 1992b This paper Shuqqat Al Khalfat, Saudi Arabia Possibly Late Miocene Buffetaut, 2022;Lowe, 1933aLowe, , 1933bPhilby, 1933 Baynunah Formation (many localities including the site of Ruwais) United Arab Emirates Late Miocene Andrews, 1999;Barry, 1999;Beech, 2005;Beech & Hellyer, 2002Beech & Higgs, 2005;Beech et al 2003;Bernor et al 2022;Bibi, 2022;Bibi et al 2006Bibi et al , 2012Bibi et al , 2013Bibi et al , 2017Bibi et al , 2022aBibi et al , 2022bBibi et al , 2022cBishop & Hill, 1999;Boisserie & Bibi, 2022;Boisserie et al 2017;De Bruijn, 1999;De Bruijn & Whybrow, 1994;Ditchfield, 1999;Eisenmann & Whybrow, 1999;Forey & Young, 1999;Friend, 1999;Gardner & Rage, 2016;Gentry, 1999aGentry, , 1999bGilbert & Hill, 2022;Gilbert et al 2014;Glennie & Evamy, 1968;Greenwood, 1987;Grohe, 2022;…”

“…Over the past nine decades, fossil struthious eggshell fragments have been reported from a variety of localities in the Arabian Peninsula (Lowe, 1933a(Lowe, , 1933bMcClure, 1984;Bibi et al 2006;Hofmann et al 2018;Al-Kindi et al 2021; Mairoano et al 2020; Rosén et al 2021;Buffetaut, 2022). The most common eggshell fragments reported from the peninsula belong to the extant ostrich, Struthio camelus (Struthio syriacus in Lowe, 1933aLowe, , 1933b.…”

“…Restudy of the eggshell fragment (NHMUK A 2043) from Shuqqat Al Khalfat, Saudi Arabia (near 21°57'13''N -49°45'41''E) described by Lowe (1933aLowe ( , 1933b as suggested by Buffetaut (2022) was undertaken in March, 2023 (Fig. 10).…”