The Green Clade grows: A phylogenetic analysis of Aplastodiscus (Anura; Hylidae)

Abstract

Green tree frogs of the genus Aplastodiscus occur in the Atlantic Forest and Cerrado biomes of South America. The genus comprises 15 medium-sized species placed in three species groups diagnosed mainly by cloacal morphology. A phylogenetic analysis was conducted to: (1) test the monophyly of these species groups; (2) explore the phylogenetic relationships among putative species; and (3) investigate species boundaries. The dataset included eight mitochondrial and nuclear gene fragments for up to 6642 bp per specimen. The results strongly support the monophyly of Aplastodiscus and of the A. albofrenatus and A. perviridis groups. Aplastodiscus sibilatus is the sister taxon of all other species of Aplastodiscus, making the A. albosignatus Group non-monophyletic as currently defined. At least six unnamed species are recognized for Aplastodiscus, increasing the diversity of the genus by 40%. A fourth species group, the A. sibilatus Group is recognized. Aplastodiscus musicus is transferred from the A. albofrenatus Group to the A. albosignatus Group, and A. callipygius is considered a junior synonym of A. albosignatus. Characters related to external cloacal morphology reveal an interesting evolutionary pattern of parallelisms and reversions, suggesting an undocumented level of complexity. We analyze, in light of our phylogenetic results, the evolution of reproductive biology and chromosome morphology in Aplastodiscus.

The first species of Aplastodiscus endemic to the Brazilian Cerrado (Anura, Hylidae)

“…Berneck et al (2016) included only one specimen of the Aplastodiscus lutzorum (as Aplastodiscus sp. 3), therefore the monophyly of the new species was tested for the first time by our analysis.…”

“…Berneck et al (2016) studied Aplastodiscus in a wider context and consequently included only one specimen of the species described here. Therefore, we carried out a reduced phylogenetic analysis that included all terminals of the Aplastodiscus perviridis Group analyzed by Berneck et al (2016) and four specimens of the species described here.…”

“…Therefore, we carried out a reduced phylogenetic analysis that included all terminals of the Aplastodiscus perviridis Group analyzed by Berneck et al (2016) and four specimens of the species described here. As outgroups, we included two terminals of the Aplastodiscus albosignatus Group and two of the Aplastodiscus albofrenatus Group, rooting the tree in the Aplastodiscus sibilatus Group (see Berneck et al 2016). The dataset used for the analysis were the fragments delimited by the primers 16sAR, Wilk2, and COI forward and reverse.…”

“…The genus Aplastodiscus includes 14 nominal species in four monophyletic groups (Berneck et al 2016) with occurrence mainly in Atlantic Forest in Brazil and Argentina (Frost 2016). The species are stream-breeding treefrogs, usually of green color and medium size.…”

“…Berneck et al (2016) recently reviewed the taxonomy and phylogenetic relationships of all Aplastodiscus species and suggested a third species for the Aplastodiscus perviridis Group, the “ Aplastodiscus sp. 3”.…”