A new species of Homonota (Reptilia: Squamata: Gekkota: Phyllodactylidae) endemic to the hills of Paraje Tres Cerros, Corrientes Province, Argentina

Abstract

The genus Homonota comprises nine South American species of terrestrial and nocturnal lizards. Homonota lizards lack the femoral pores typical of other South American Phyllodactylidae, and their infradigital lamellas are not expanded. We here describe a new species, Homonota taragui sp. nov., exclusively found on a small group of three hills up to 179 meters above sea level in central eastern Corrientes Province, Argentina. The new species differs from other Homonota species by a combination of characters, including: a well-marked dorsal, reticulate, dark pattern contrasting with a lighter colored background; small, star-shaped chromatophores on the abdomen; the post-orbital region of the head covered by granular scales; the dorsal and anterior regions of the thighs covered by keeled scales interspersed with cycloid scales; and the internasal scale in contact with rostral scales. The conservation status of Homonota taragui sp. nov. may be vulnerable, due to its localized endemism with populations on three small hills surrounded by intense agricultural and livestock activity. Two endemic plant species are known from these hills, and this new lizard represents the first endemic animal species.

Multiple approaches to understanding the taxonomic status of an enigmatic new scorpion species of the genus Tityus (Buthidae) from the biogeographic island of Paraje Tres Cerros (Argentina)

“…curupi occurs, apparently remained alongside these marine floods. Due to this, and to its particular geomorphology, clearly different from the surrounding areas, several endemic species of animals and plants have evolved there [18, 19, 20, 13, 14]. Our group recently published a dated molecular phylogeny of South American Buthidae which strongly supports this hypothesis [11].…”

“…This is an isolated low altitude hilly area of subtropical western Argentina composed of three rocky isolated hills of 150–180 m asl of quartz sandstone [12, 13, 14], corresponding to the Botucatu stratigraphic formation (Figs 1A and 2) [15]. Two hypotheses are currently being considered to explain the emergence of these hills: 1) a relatively early emergence, about 10–5 million years ago (Ma), related to the final rapid uplift of the Andes [16, 17], or 2) a much older Gondwanic origin.…”

“…Two hypotheses are currently being considered to explain the emergence of these hills: 1) a relatively early emergence, about 10–5 million years ago (Ma), related to the final rapid uplift of the Andes [16, 17], or 2) a much older Gondwanic origin. Due to their different environmental conditions with respect to their surrounding areas, these hills have been a “biogeographic island” for a long time, and they host several endemic species of plants [18, 19, 20] and small vertebrates [13, 14]. As a result of these campaigns our research group collected several new endemic species of epigean fauna, including an enigmatic new scorpion species: Tityus curupi n. sp.…”

Description of a new species of Homonota (Reptilia, Squamata, Phyllodactylidae) from the central region of northern Paraguay

“…The diversity of species groups within the genus Homonota was explored in the last decade, and resulted in the description of H. williamsii (Avila et al 2012) of the whitii group, and H. rupicola (Cacciali et al 2007b) and H. taragui (Cajade et al 2013) of the borellii group. However, the taxonomy of the horrida group (referred to as fasciata in Morando et al 2014) was untouched for many years, and was comprised of two species (H. horrida and H. underwoodi).…”

“…Both species were considered synonyms by Abdala and Lavilla (Peracca, 1897), H. uruguayensis (Vaz-Ferreira & Sierra de Soriano, 1961), H. rupicola Cacciali, Ávila &Bauer, 2007, andH. taragui Cájade, Etchepare, Falcione, Barrasso &Álvarez, 2013; and the horrida group (indicated as fasciata group by Morando et al 2014) which contains H. horrida (Burmeister, 1861), H. underwoodi Kluge, 1964, and H. septentrionalis Cacciali, Morando, Medina, Köhler, Motte & Avila, 2017. Cacciali et al (2017 suggested that more revisions are needed to understand the true taxonomic status of H. fasciata because currently it is not possible to know to which group it belongs and it is considered incertae sedis.…”