A new species of Amazonian snouted treefrog (Hylidae:Scinax) with description of a novel species-habitat association for an aquatic breeding frog

Abstract

The genus Scinax is one of the most specious genera of treefrogs of the family Hylidae. Despite the high number of potential new species of Scinax revealed in recent studies, the rate of species descriptions for Amazonia has been low in the last decade. A potential cause of this low rate may be the existence of morphologically cryptic species. Describing new species may not only impact the taxonomy and systematics of a group of organisms but also benefit other fields of biology. Ecological studies conducted in megadiverse regions, such as Amazonia, often meet challenging questions concerning insufficient knowledge of organismal alpha taxonomy. Due to that, detecting species-habitat associations is dependent on our ability to properly identify species. In this study, we first provide a description of a new species (including its tadpoles) of the genus Scinax distributed along heterogeneous landscapes in southern Amazonia; and secondly assess the influence of environmental heterogeneity on the new species’ abundance and distribution. Scinax ruberoculatus sp. nov. differs from all nominal congeners by its small size (SVL 22.6–25.9 mm in males and 25.4–27.5 mm in females), by having a dark brown spot on the head and scapular region shaped mainly like the moth Copiopteryx semiramis (or a human molar in lateral view, or a triangle), bicolored reddish and grey iris, snout truncate in dorsal view, bilobate vocal sac in males, by its advertisement call consisting of a single pulsed note with duration of 0.134–0.331 s, 10–23 pulses per note, and dominant frequency 1,809–1,895 Hz. Both occurrence and abundance of the new species are significantly influenced by silt content in the soil. This finding brings the first evidence that edaphic factors influence species-habitat association in Amazonian aquatic breeding frogs.

Geographic distribution of Scinax onca (Anura: Hylidae) and the frst record of its occurrence in Peru

“…During the last decade, 16 new taxa of neotropical snouted treefrogs of the genus Scinax Wagler, 1830 have been described , Pugliese et al 2009, Nunes and Pombal 2010, 2011, 2012, Brusquetti et al 2014, Sturaro and Peloso 2014, Araujo-Vieira et al 2015, Juncá et al 2015, Conte et al 2016, Ferrão et al 2017, Acosta-Galvis 2018, Ron et al 2018. The total of 72 species in Scinax confirms its status as one of the most diverse among treefrogs (Ferrão et al 2018, Frost 2018. Only one of the recently described species, Scinax iquitorum Moravec, Tuanama, Pérez-Peña, and Lehr, 2009, occurs in Peruvian territory.…”

Soil and forest structure predicts large-scale patterns of occurrence and local abundance of a widespread Amazonian frog

“…Elevation ranges from 27 to 80 m above sea level ( Sombroek, 2000 ). Temporary ponds occur in lower areas during the rainy season and are formed by undulating terrain ( Rossetti, Toledo & Góes, 2005 ; Ferrão et al, 2018 ). A more detailed description of the study area is presented by Cintra et al (2013) and Schietti et al (2016) .…”

“…We were careful not to record the same individual more than once on the same segment or in neighboring segments. Sampling was carried out during the breeding season, which coincides with the regional rainy season ( Kaefer et al, 2012 ; Ferrão et al, 2018 ), between December and February 2010–2015.…”

A weighting method to improve habitat association analysis: tested on British carabids

“…Information on habitat associations is generally derived from expert knowledge (Lonsdorf et al 2009) or analysis over a small geographic area (Ball et al 2013, De Lima et al 2016, Ferrão et al 2018 and is often limited to associations with a single habitat or a few broad habitats (Webb et al 2017). Large-scale analysis of habitat association de-emphasises the less frequent recordings of a species in a habitat in which the species is transient, which could be misconstrued at a small-scale as association.…”