Rediscovery of the rare tree frog Hyla inframaculata Boulenger, 1882 (Anura: Hylidae), in Amazonian Brazil with notes on variation and distribution, and its generic allocation

Abstract

Hyla (= Osteocephalu.s) inframaculata was described on the basis of one specimen collected more than 130 years ago in the neighbourhood of Santarém, Para, Brazil. Only in 2001 three new specimens were collected in the Belo Monte area of the Xingu River, Para, and ten more in late 2011 and 2012 in the same area. The distribution of the species seems to be restricted to "terra firme" (= not flooded) and temporarily flooded forest between the Tapajós and Xingu rivers, in a band south of the Amazon River. The new material deposited in MPEG is described, morphometric data for males, females and a half grown are provided and some conclusions in the literature are corrected. A new diagnosis is presented. The species seems to belong to the genus Dryaderces.

Rediscovery of Osteocephalus vilarsi (Anura: Hylidae): an overlooked but widespread Amazonian spiny-backed treefrog

“…With 24 currently recognised species, the genus Osteocephalus represents the most specious genus of the subfamily Lophyohylinae Miranda-Ribeiro, 1926 (Frost, 2019). The increasing attention paid to spiny-backed treefrog systematics and biogeography in the last decade (Moravec et al, 2009; Jungfer, 2010; Ron et al, 2010, 2012; Hoogmoed, 2013; Jungfer et al, 2013, 2016; Moravec et al, 2016) has significantly improved our knowledge on Osteocephalus phylogeny, resulting in nomenclatural and biogeographical corrections, descriptions of new taxa and the definition of new candidate species. Among the presently accepted species, O. vilarsi (Melin, 1941) is known only from its holotype and represents the most enigmatic species of Osteocephalus (Jungfer et al, 2013; Frost, 2019).…”

Notes on external morphological variation, natural history, and distribution of Dryaderces inframaculata (Anura: Hylidae), a rare neotropical treefrog

“…Jungfer (2010) placed Hyla inframaculata in the genus Osteocephalus, and Hoogmoed (2013) then placed O. inframaculatus (Boulenger, 1882) in Dryaderces; consequently, the genus contains two species-D. inframaculata (Boulenger, 1882) and D. pearsoni (Gaige, 1929)-and a third species is being described (Jungfer et al 2013). Dryaderces occurs on the lower Andean slopes of central Peru to the Bolivian Amazon, and in the area between the Tapajós and Xingu rivers in a band south of the Amazon River in the states of Pará and Mato Grosso in Brazil (Hoogmoed 2013, Frost 2017.…”

“…Similarly, neither Knispel and Barros (2009) collecting in Altamira, nor Oliveira et al (2013) working west of the Belo Monte area, found D. inframaculata. Hoogmoed (2013) examined seven individuals (3 males, 3 females, and a half-grown specimen) collected in 2001 and 2012 in the area of the hydroelectric plant of Belo Monte, Rio Xingu, Vitória do Xingu in the state of Pará, Brazil. These specimens were compared with the holotype of D. inframaculata (BMNH 1947.2.13.10).…”

“…Only few habitat data are available (Hoogmoed 2013). However, if the localities of the recently collected Dryaderces inframaculata are projected on a Google Earth image map (dated December 2011) of the Vitória do Xingu area ( Figure 3A), we can infer that most the frogs occurred in forested areas.…”

“…Now most of the localities from which D. inframaculata were collected have disappeared under water of Belo Monte Lake ( Figure 3B). Hoogmoed (2013) posited that the species should be considered vulnerable, or even endangered, because most of its range in Vitória do Xingu would be destroyed by roads, canals, lakes, and other infrastructural constructions related to the hydroelectric dam of Belo Monte; this is exactly what happened as is shown in Figure 3B. The fact that D. inframaculata is known to occur in four localities distant from Belo Monte (Pinto et al 2017) should positively influence the conservation status of this species.…”