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Wednesday, February 27th, 2019
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| 10:32a | [Herpetology • 2019] Nymphargus manduriacu • A New Glassfrog (Centrolenidae) from the Chocó-Andean Río Manduriacu Reserve, Ecuador, Endangered by Mining
Abstract We describe a new glassfrog from Río Manduriacu Reserve, Imbabura Province, on the Pacific slopes of the Ecuadorian Andes. The new species can be distinguished from most other glassfrogs by having numerous yellow spots on the dorsum and lacking membranes among fingers. Both morphological and molecular data support the placement of the species in the genus Nymphargus. We present a new mitochondrial phylogeny of Nymphargus and discuss the speciation patterns of this genus; most importantly, recent speciation events seem to result from the effect of the linearity of the Andes. Finally, although the new species occurs within a private reserve, it is seriously endangered by mining activities; thus, following IUCN criteria, we consider the new species as Critically Endangered.
  
 
Nymphargus manduriacu new species Common names. English: Manduriacu glassfrog. Spanish: Rana de Cristal de Manduriacu. Diagnosis. Nymphargus manduriacu sp. nov. is distinguished from most glassfrogs by lacking webbing between inner fingers and having, in life, a grayish green dorsum with numerous yellow spots, which sometimes are surrounded by an ill-defined black ring (i.e., false ocelli). On the Pacific slopes of the Ecuadorian and Colombian Andes, there are very few species that share the two aforementioned traits with N. manduriacu sp. nov.; these species are: N. buenaventura, N. ignotus, N. spilotus, and N. luminosus. Differences among these species are summarized in Table 1 and Figs. 5 and 6. The sister species of N. manduriacu sp. nov. is N. balionotus, which is easily differentiated by its unique dorsal color pattern, a green dorsum with several black and occasionally yellow to cinnamon blotches (Duellman, 1981; Arteaga-Navarro, Bustamante & Guayasamin, 2013). Also, the uncorrected p genetic distance between N. manduriacu sp. nov. and N. balionotus is 6.4–6.7% for the 12S and 16S concatenated matrix. .... Evolutionary relationships of the new species. Given the gene and taxon sampling of our study, Nymphargus manduriacu sp. nov. is sister to N. balionotus. The latter taxon was considered to be as incertae sedis within the subfamily Centroleninae (Guayasamin et al., 2009). Here, we formally place Centrolenella balionota Duellman, 1981 in the genus Nymphargus sensu Guayasamin et al., 2009. Nymphargus manduriacu sp. nov. and N. balionotus are endemic to the Pacific slopes of the northern Andes, and are found syntopically at RMR. Distribution. Nymphargus manduriacu is only known from a few nearby streams within the Río Manduriacu Reserve, Imbabura province, on the Pacific slopes of the Andes of Ecuador (Fig. 1). Based on these limited records, the species occupies a narrow elevational range of 1,215–1,242 m. Conservation status. We recommend that N. manduriacu should be considered as Critically Endangered, following IUCN (2001) criteria B2a (known to exist from a single locality) and B2biii (continuing decline, observed, inferred or projected, in area, extent and/or quality of habitat). The main threats for the species are habitat destruction and contamination associated with cattle ranching, agriculture and, most seriously, mining activities (see Discussion; Fig. 8). Although RMR is still poorly surveyed, northwestern Ecuador has been the target of intense herpetological research (e.g., Lynch & Duellman, 1973, 1997; Arteaga-Navarro, Bustamante & Guayasamin, 2013; Arteaga et al., 2016), including areas nearby RMR (i.e., Reserva Los Cedros; Hutter & Guayasamin, 2015); thus, the restricted distribution of the new species is, most likely, real. Etymology. The specific epithet “manduriacu” is a noun in apposition and refers to the type locality of the species, Río Manduriacu Reserve, a conservation area managed by Fundación EcoMinga (ecomingafoundation.wordpress.com). Conclusions: We provide morphological, genetic, and acoustic evidence that support the validity of a new species, Nymphargus manduriacu. Also, we infer a new mitochondrial phylogeny of the genus Nymphargus that allows us to reveal speciation patterns in this taxon, mainly that recent speciation events in this genus seem to be heavily influenced by the linearity of the Andes and dry river-valleys that are run transversal to this mountain range. Finally, the new species is considered as Critically Endangered because of its restricted distribution, habitat destruction and contamination associated with cattle ranching, agriculture and, most seriously, mining activities. At Río Manduriacu Reserve, mining has become one of the most dangerous threats to biodiversity, especially to species with highly restricted distributions. Juan M. Guayasamin, Diego F. Cisneros-Heredia, José Vieira, Sebastián Kohn, Gabriela Gavilanes, Ryan L. Lynch, Paul S. Hamilton and Ross J. Maynard. 2019. A New Glassfrog (Centrolenidae) from the Chocó-Andean Río Manduriacu Reserve, Ecuador, Endangered by Mining. PeerJ. 7:e6400. DOI: 10.7717/peerj.6400 | ||||||||||||
| 10:47a | [Botany • 2019] Taxonomy, Evolution and Phylogeography of the Genus Helonias (Melanthiaceae) Revisited
Abstract This paper reviews the taxonomy, evolution and phylogeographic aspects of the genus Helonias L. sensu lato, including Ypsilandra and Heloniopsis (Melanthiaceae) that are basically similar in many morphological and ecological characters to Helonias sensu stricto. It includes three parts, I–III. In Part I, characters and their variation are examined to determine generic traits and diversity. In Part II, an attempt is made to taxonomically determine diversity among individuals. Taxonomic conclusions and revisions are principally the following: Helonias comprises 12 species, which are classified into two sections, H. sect. Helonias and H. sect. Heloniopsis comb. & stat. nov. Helonias sect. Helonias consists of H. bullata only; H. sect. Heloniopsis comprises two subsections, H. subsect. Ypsilandra comb. & stat. nov. and H. subsect. Heloniopsis. Helonias subsect. Ypsilandra is composed of five species previously published under the genus Ypsilandra. Helonias subsect. Heloniopsis consists of two series, H. ser. Umbellatae ser. nov., with three species from Taiwan and the Nansei Islands (incl. the Ryukyus), Japan, and H. ser. Heloniopsis, with three species from Japan, Korea and E. Russia (southern Sakhalin). Helonias yunnanensis var. mesostyla is described as a new variety from N Myanmar and SW China (NW Yunnan). The new combinations Helonias koreana (from Korea) and H. parviflora (from China) are proposed. Lectotypes for Ypsilandra parviflora, Y. thibetica, Y. yunnanensis var. micrantha, Heloniopsis breviscapa and H. grandiflora are designated. A revised typification for Sugerokia japonica is proposed, negating a previous lectotypification. Heloniopsis tubiflora is reduced to synonymy under Helonias koreana. In Part III, the evolutionary and phylogeographic aspects of Helonias are discussed, and a phylogram inferred from cladistic analysis of phenotypic characters is presented. In the phylogram, Helonias is monophyletic, while H. sect. Helonias and H. subsect. Ypsilandra are respectively paraphyletic, and H. subsect. Heloniopsis is monophyletic. Incongruence in results between morphological and DNA sequence analyses is briefly discussed. Keywords: character evolution, breeding system, floral structure, Heloniadeae, historical biogeography, infrageneric system, life history, phenology, Monocots  Noriyuki Tanaka. 2019. Taxonomy, Evolution and Phylogeography of the Genus Helonias (Melanthiaceae) Revisited. Phytotaxa. 390(1); 1–84. DOI: 10.11646/phytotaxa.390.1.1 |
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