Osteocephalus taurinus, Steindachner, 1862

Ortiz, Diego A., Hoskin, Conrad J., Werneck, Fernanda P., Réjaud, AleXandre, Manzi, Sophie, Ron, Santiago R. & Fouquet, Antoine, 2023, Historical biogeography highlights the role of Miocene landscape changes on the diversification of a clade of Amazonian tree frogs, Organisms Diversity & Evolution (New York, N. Y.) 23 (2), pp. 395-414 : 410

Osteocephalus taurinus group

The majority rule consensus delimited two OTUs within the Osteocephalus taurinus group ( Fig. 1a ). The first OTU (labelled here as Osteocephalus aff. taurinus ), containing two sequences from Amazonian Peru in western Amazonia , corresponds to an early diverging lineage within this group; it was previously labelled as O. taurinus [Ca1] CCS by Jungfer et al. (2013). The second OTU contains all the rest of sequences of O. taurinus Steindachner, 1862 ( Fig. 3g in the Appendix) and O. oophagus Jungfer & Schiesari, 1995 ( Fig. 3h in the Appendix) through Amazonia . Since both species differ in morphology and reproduction, this case represents another example of failure in detected them as different given the low divergence in 16S. Osteocephalus taurinus is considerably larger than O. oophagus , O. taurinus males have paired, lateral vocal sacs (single and subgular in O. oophagus males), dorsal tubercles with queratinized tips are abundant and prominent on dorsal surfaces in O. taurinus males and those may be also present but less noticeable in females (very few tubercles and barely discernible in O. oophagus males). Osteocephalus taurinus is an explosive pond-breeder with large clutch sizes of ~2000 eggs and parental care absent ( O. oophagus has a small clutch of ~ 30 eggs which is laid within small water cavities of trees and leaf axils of terrestrial/epiphytic plants; water cavities are used by one pair at a time which also display parental care) ( Jungfer & Weygoldt, 1999; Lima et al., 2006). These differences led us to include one terminal for each of these two species from their type locality in the mitogenomic matrix ( Fig. 1a ). The O. taurinus group contains several geographically structured mtDNA lineages (Electronic Supplement 4), and four of them have been suggested to correspond to candidate species (‘ O. taurinus [Ca2–5] UCS’; Jungfer et al., 2013). However, we did not include additional terminals in the mitogenomic matrix for them because of their current lack of morphological and bioacoustics information. We considered them here part of O. taurinus ; however, further systematic study and more variable markers are needed to delimit species and population structure within this widespread taxon.

Figures

Fig. 1 Panel a, time-calibrated phylogeny of Osteocephalus, Tepuihyla and Dryaderces in Amazonia, resulting from a mitogenomic analysis in BEAST and displaying the mean and 95% CI (blue bars) of divergences. Nodes are numbered in red (age details are in Electronic Supplement 1), and support values are depicted for Bayesian (following node symbol colours) and maximum likelihood analyses (following numbers below the nodes). Topological discrepancies between analyses for four low-supported nodes (21, 25, 34 and 43)

Fig. 3 Dorsolateral views of Osteocephalus. a O. albogutta- tus sensu stricto, QCAZ15972, Puyo-Canelos Road, Pastaza, Ecuador. b O. mimeticus sensu stricto, AF4442 (sequenced), San José, San Martín, Peru. c O. buckleyi sensu stricto, Canelos, Pastaza, Ecuador. d O. vilmae, QCAZ51205, Pompeya-Iro Road km 80, Orellana, Ecuador. e O. mutabor, QCAZ56066, Lorocachi, Pastaza, Ecuador. f O. mutabor, QCAZ39588, Río Pucayacu, Pastaza, Ecuador. g O. taurinus sensu stricto, Reserva Ducke, Amazonas, Brazil. h O. oophagus sensu stricto, Reserva Ducke, Amazo- nas, Brazil. Photographs: a, d–f by Santiago Ron (BIOWEB, Licence: CC BY-NC-ND 4.0); b by Antoine Fouquet; c, g–h by Diego Ortiz