The poverty of adult morphology: Bioacoustics, genetics, and internal tadpole morphology reveal a new species of glassfrog (Anura: Centrolenidae: Ikakogi) from the Sierra Nevada de Santa Marta, Colombia

Abstract

Ikakogi is a behaviorally and morphologically intriguing genus of glassfrog. Using tadpole morphology, vocalizations, and DNA, a new species is described from the Sierra Nevada de Santa Marta (SNSM), an isolated mountain range in northern Colombia. The new taxon is the second known species of the genus Ikakogi and is morphologically identical to I . tayrona (except for some larval characters) but differs by its genetic distance (14.8% in mitochondrial encoded cytochrome b MT-CYB ; ca. 371 bp) and by the dominant frequency of its advertisement call (2928–3273 Hz in contrast to 2650–2870 Hz in I . tayrona ). They also differ in the number of lateral buccal floor papillae, and the position of the buccal roof arena papillae. Additionally, the new species is differentiated from all other species of Centrolenidae by the following traits: tympanum visible, vomerine teeth absent, humeral spines present in adult males, bones in life white with pale green in epiphyses, minute punctuations present on green skin dorsum, and flanks with lateral row of small, enameled dots that extend from below eye to just posterior to arm insertion. We describe the external and internal larval morphology of the new species and we redescribe the larval morphology of Ikakogi tayrona on the basis of field collected specimens representing several stages of development from early to late metamorphosis. We discuss the relevance of larval morphology for the taxonomy and systematics of Ikakogi and other centrolenid genera. Finally, we document intraspecific larval variation in meristic characters and ontogenetic changes in eye size, coloration, and labial tooth-rows formulas, and compare tadpoles of related species. Ikakogi tayrona has been proposed as the sister taxon of all other Centrolenidae; our observations and new species description offers insights about the ancestral character-states of adults, egg clutches, and larval features in this lineage of frogs.

Tadpole of the Amazonia frog Edalorhina perezi (Anura: Leptodactylidae) with description of oral internal and chondrocranial morphology

“…A vent tube with dextral opening is found in Edalorhina , Engystomops , and most Physalaemus (Table S4). Among Leiuperinae, most Pleurodema and Pseudopaludicola have a medial vent tube (Andrade, Ferreira, Takazone, Libório, & Weber, 2018; Barrasso, Alcalde, Martinazzo, & Basso, 2012; Cei, 1980; Galvani, Gonzalez, Sanabria, & Quiroga, 2012; Kher & Schaefer, 2005; Kolenc et al, 2009; Laufer & Barreneche, 2008; Lobo, 1991; Magalhães, Loebmann, Kokubum, Haddad, & Garda, 2014; Pereira & Nascimento, 2004; Schulze et al, 2015; Toledo, 2010), a character‐state also found in most genera of Leptodactylidae (e.g., Almeida & Angulo, 2006; de Sá, Langone, & Segalla, 2007; Grosso, 2015; Heyer & Silverstone, 1969; Lamar & Wild, 1995; Magalhães, Garda, Amado, & de Sá, 2013; Menin, de Almeida, & Kokubum, 2009; Menin, Lima, & Rodrigues, 2010; Mêrces, Magalhaes, Amado, Junca, & Garda, 2015; Rossa‐Feres & Nonura, 2006; Schulze et al, 2015; Zaracho & Kokubum, 2017) as well as in many Centrolenidae, the sister group of Leptodactylidae (Jetz & Pyron, 2018; for centrolenids tadpoles, see Rada et al, 2019 and references therein). When we optimize this character on the phylogeny of Leiuperinae provided by Jetz and Pyron (2018), the presence of a dextral vent tube emerge as a synapomorphy of Edalorhina , Engystomops , and Physalaemus (Figure 7).…”

The remarkable larval anatomy of Proceratophrys minuta Napoli, Cruz, Abreu and Del‐Grande, 2011 (Amphibia: Anura: Odontophrynidae)

“…Larval morphology is an exciting field, and despite tadpoles having been studied for over 100 years (e.g., Boulenger, 1892; Lataste, 1879; Noble, 1929; Orton, 1953), as more species are investigated, new characters are described (e.g., Dias, Araújo‐Vieira, Santos, & Both, 2019b; Dias, Mongin‐Aquino, et al, 2018a; Haas et al, 2014; Rada et al, 2019; Rowley, Tran, Le, Hoang, & Altig, 2012; Vera Candioti et al, 2017). Even in phenotypically conserved lineages such as the genus Proceratophrys , new characters can be discovered as is the case of P. minuta .…”

Morphological and molecular data reveal new country records and distribution extensions of some glassfrogs (Anura: Centrolenidae) for Colombia

“…The recent discovery of new species and new country records (e.g. Velásquez-Álvarez et al 2007;Rada et al 2017aRada et al , 2017bRada et al , 2019Thompson et al 2018; this work) exemplify this scenario. Thus, similar results are expected as fieldwork continues in poorly explored areas, such as the Andean/Amazonian and Andean/Chocoan forests.…”

“…Although Lynch et al (1997) estimated that only 10% of the centrolenid diversity in Colombia remained to be discovered, the number of species known to occur in the country has increased to 79 at present (Frost 2020). However, this number remains uncertain because taxonomic studies and fieldwork often result in names being resurrected or placed in synonym, the description of new taxa (Velásquez-Álvarez et al 2007;Guayasamin et al 2008;Rada et al 2017aRada et al , 2017bRada et al , 2019 and distribution extensions of species, including new country records (Malambo et al 2013(Malambo et al , 2017Molina-Zuluaga et al 2017;Thompson et al 2018).…”