Anisian Triassic Diapsid Megachirella wachtleri Redescribed

Redescription and phylogenetic relationships of Megachirella wachtleri Renesto et Posenato, 2003 (Reptilia, Diapsida)

Authors:

1. Silvio Renesto (a)
2. Massimo Bernardi (b,c)

Affiliations:

a. DISTA Dipartimento di Scienze Teoriche ed Applicate, Universita` degli Studi dell’Insubria, Via Dunant 3, 21100 Varese, Italy

b. Museo delle Scienze, Via Calepina 14, 38100 Trento, Italy

c. School of Earth Sciences, University of Bristol, Bristol BS8 1RJ, UK

Abstract:

Megachirella wachtleri Renesto et Posenato, 2003, a well preserved partial reptile skeleton from the Middle Triassic of the Dolomites (N. Italy), was originally considered a lepidosauromorph, but no phylogenetic analysis was carried out. Consequently, the taxon was overlooked in later phylogenetic analyses of the Diapsida. Here, the holotype and only known specimen of M. wachtleri is redescribed, allowing an investigation of its phylogenetic relationships. Phylogenetic analyses confirm that Megachirella is a lepidosauromorph close to the crown group lepidosaurs (Squamata + Rhynchocephalia). Megachirella enhances our knowledge of the series of morphological modifications that led to the origin of the Lepidosauria, the most diverse clade of extant reptiles.