Reappraisal of the taxonomic status of Amphisbaena prunicolor (Cope 1885) and Amphisbaena albocingulata Boettger 1885 (Amphisbaenia: Amphisbaenidae)

Abstract

We revised the taxonomic status of Amphisbaena prunicolor and A. albocingulata, two taxa traditionally recognized assubspecies of A. prunicolor in the A. darwini complex. Despite some authors elevated both taxa to the specific rank, itstaxonomic decisions were made without specific commentaries and/or proper diagnostic characters. The comparison ofmorphological characters between the two taxa with other similar species, associated with A. darwini (A. darwini, A.heterozonata, A. munoai and A. trachura), revealed a unique combination of diagnostic characters. Amphisbaena pruni-color and A. albocingulata were considered distinct species, diagnosable by the presence of the postmalar row in A. pru-nicolor, absent in A. albocingulata and by the ventral colour pattern uniform (pale brown) in A. albocingulata andcheckerboard (brown-purplish and white) in A. prunicolor. We also provided a redescription of the two species, information on intraspecific variation in A. munoai and suggested the extension of the distribution of A. darwini to southern Brazil.

REDISCOVERY OF Amphisbaena prunicolor (Cope, 1885) (Squamata, Amphisbaenidae) IN PARAGUAY

“…The scale count are 197 body annuli, 19 caudal annuli, 14 dorsal and 17 ventral segments at midbody annulus, 3/3 supralabials and 3/3 infralabials plate, rounded snout, four precloacal pores, presence of postmalar row (Figure 2A-C). Also, the specimen has light ventral coloration pattern ( Figure 3A-B) which matches with the diagnosis presented by Perez et al (2012) for differentiated Amphisbaena prunicolor from A. albocingulata. The habitat where the specimen was found corresponds to the ecoregion Mesopotamian grasslands according to Avila et al (2018).…”

“…In Paraguay eleven species are recorded (Cacciali et al 2016), many of those species such as Amphisbaena angustifrons, A. prunicolor, A. leeseri and A. steindachneri have only a few records (Cacciali et al 2016), which make distribution on these species very fragmented for the country. Among these poorly known Paraguayan species, Amphisbaena prunicolor is a medium-sized worm lizard distributed in northern Argentina (Corrientes and Misiones Provinces), south of Brazil (from Rio Grande do Sul to Espírito Santo States) and south of Paraguay (Perez et al 2012, Cacciali et al 2016. The only known record for Paraguay was reported from Itapúa department, 3 km northeast of Encarnación (Montero & Terol 1999, Cacciali et al 2016, and the specimen (CM 109119) was last collected in 1984 by I. Gamarra, housed in Carnegie Museum of Natural History (Pittsburgh, USA) (Montero &Terol 1999).…”

“…Gans (1966) recognized two subspecies for A. prunicolor: A. p. prunicolor and A. p. albocingulata, later, Vanzolini (2002) elevated A. prunicolor and A. albocingulata to full species and Perez et al (2012) analyzed the variation of both species. Amphisbaena albocingulata has no precise type locality (cited only as Paraguay in the original description).…”

“…According to Perez et al (2012) Amphisbaena prunicolor has a rounded snout, the nasal shields are in contact on the dorsal part of the head, caudal autotomy is externally visible, presence of four precloacal pores, 3/3 supralabials and infralabials, body annuli 181 -215, caudal annuli 18 -24, dorsal and ventral segments 10 -17 and 14 -20 respectively at the midbody, and presence of postmalar row which is the main difference for differentiating it from A. albocingulata (absence of postmalar row). Also, it differs from this species by presenting a venter light checkerboard coloration pattern.…”

An updated diagnosis of the rare Amphisbaena slateri Boulenger, 1907, based on additional specimens (Squamata, Amphisbaenia, Amphisbaenidae)

“…Knowledge on the systematics of South American amphisbaenians has rapidly advanced in recent years, with the description of many new species and the proposals of phylogenetic relationships Vieites 2009, Colli et al 2016). These advances, however, are mostly related to Brazilian species, and little has been published in this decade on the taxonomy of species from other South American countries (Perez et al 2012, Ribeiro et al 2015, Montero 2016, Costa et al 2018. Given the apparent rarity of A. slateri and the scarce information on its morphology, it is important to unveil the existence of the above-cited specimens and to provide an updated description for this taxon, comparing it with other species from Bolivia and Peru.…”