Mini Scherz & Hutter & Rakotoarison & Riemann & Rödel & Ndriantsoa & Glos & Roberts & Crottini & Vences & Glaw 2019, gen. nov

Mini gen. nov. urn:lsid:zoobank.org:act: 67171236-00A2-428B-8194-584BF52E84E6 (Figs 2–9, Table 1) Type species. Mini mum sp. nov. Contents. Mini mum sp. nov., M. scule sp. nov., and M. ature sp. nov. Etymology. The genus name is derived from English prefix ‘mini-’, denoting a small version of an object. We treat this name as an arbitrary combination of letters in the sense of the International Code of Zoological Nomenclature Articles 30.1.4.1 and 30.2.2, and we assign it the feminine gender. We have searched all available taxonomic databases and could not find any evidence that this name has ever been used to refer to a genus of animals, and we therefore conclude that it is available. Diagnosis. Diminutive terrestrial frogs (adult SVL 8.2–14.9 mm), assigned to the Madagascar-endemic subfamily Cophylinae on the basis of divided vomers, procoelous vertebral column, divided sphenethmoids, and genetic affinities. Skin smooth to slightly granular, occasionally iridescent. A lateral colour border is present but varies in intensity among species. Highly reduced fingers and toes, fusion or loss of carpal 2, and paedomorphic skull morphology: laterally displaced narrow nasals, teeth absent from vomer, in some species present on the maxilla and premaxilla, otic capsule sometimes dorsally ossified, brain case comprising most of the skull’s length and width. All members of the genus Mini gen. nov. resemble miniaturised to extremely miniaturised members of the genus Stumpffia. However, all species can be distinguished from Stumpffia on the basis of their curving clavicles and a fused or lost carpal 2. In the species accounts below, we provide detailed distinctions from Stumpffia relevant to each species. Justification. The erection of the genus Mini is justified by significant genetic differentiation from all other major cophyline lineages (see Fig 1), by the fact that it does not form a monophyletic group with the genus Stumpffia, and furthermore by the strong morphological differences (including but not restricted to the much smaller size) to all species of its sister clade, Plethodontohyla. The following characters distinguish the genus from all Plethodontohyla species, including juveniles: digital reduction of the fingers and toes (vs no reduction), laterally displaced and reduced nasals (vs large nasals situated anterior to frontal), parasphenoid cultriform process shorter than frontoparietals (vs roughly equal in length to the frontoparietals) and considerably narrower than alary processes (vs as wide or wider), vomerine teeth absent (vs present), carpal 2 absent (vs present). Uncorrected p-distances between Mini and Plethodontohyla range from 8.3–13.3% in the 3’ fragment of 16S rRNA analysed here, and they have been found to be sister to Plethodontohyla in all phylogenetic analysis since their first inclusion in genetic datasets [15, 17, 20, 22] (except the DNA barcoding study of Vieites et al. [40], where they were placed at the base of Rhombophryne + Stumpffia + Anilany, but that study lacks any resolution at deep nodes, and was not intended to provide phylogenetic hypotheses at deep levels). Distribution. The genus Mini is apparently endemic to low-elevation habitats (0–350 m a. s. l.) of southeastern Madagascar (Fig 3).