Wikinews interviews Paúl M. Velazco about new yellow-shouldered bat species

Monday, April 21, 2014 

Paul Velazco with a Vampyrum spectrum.
Image: Marco Tschapka.

Distribution range of species formerly ascribed to Sturnira lilium (gray tone) and the type localities (stars) of species in the S. lilium complex.
Image: Paúl M. Velazco.

Scientists at Chicago's Field Museum and New York's American Museum of Natural History have discovered three new species of yellow-shouldered bats, genus Sturnira, in the Neotropics. On Wednesday open-access journal ZooKeys published their paper on two of the new species, Sturnira bakeri and Sturnira burtonlimi. The two new species were previously confused with S. ludovici, and S. lilium and S. luisi, respectively. With the discovery, genus Sturnira now has the most species of any genus in family Phyllostomidae, the leaf-nosed bats.

Species S. bakeri was named after Dr. Robert J. Baker, who "has made enormous contributions to our [Authors of the ZooKey paper] understanding of bats, particularly to the evolution of Neotropical phyllostomids"; and S. burtonlimi after Dr. Burton K. Lim, who "collected the type series of this species and has made many other important collections throughout the Neotropics and beyond", the authors noted in the paper.

Within the New World tropics, the distribution range of the genus, the new species' known living areas are in Costa Rica and Panama for S. burtonlimi, and Western Ecuador for S. bakeri. The researchers identified differences between different specimens, including those in their teeth, skull shapes, and DNA sequences.

Wikinews interviewed one of the chiropterologists, Paúl M. Velazco of the American Museum of Natural History, about the study.

((Wikinews)) The Sturnira genus now has 22 species, over 1.5 times larger than it was a year ago (14 species). Who contributed to this change? Did you participate throughout the entire process, or only the discovery of the last 2 species?

Paúl M. Velazco: The last Mammal Species of the World (Simmons, 2005) recognized 14 species for Sturnira. Since then three new species have been described [S. sorianoi Sánchez-Hernández et al., 2005; S. koopmanhilli McCarthy et al., 2006; and S. perla Jarrín-V. and Kunz, 2011] and one subspecies was elevated to the species level (S. hondurensis) by Gardner (2008). This brought the number of species of Sturnira to 18 by 2011. Along with my coauthor Bruce Patterson, we generated the most comprehensive phylogeny of the genus. For this we sequenced two nuclear and three mitochondrial genes from the liver or muscle tissue that had been frozen or preserved from each bat specimen, isolating nearly 5,000 base pairs of DNA. These sequences were obtained from specimens we have collected in the past (38) and from tissues we borrowed from different natural history collections. We published this phylogeny last year in the journal Molecular Phylogenetics and Evolution. Results of this study found that two subspecies of Sturnira lilium should be recognized as valid species (S. parvidens and S. paulsoni). Additionally we found three new species, two of them described in the ZooKeys paper. The third one hopefully will be published later this year.

((WN)) The genus is called Sturnira Gray in the paper. I've not seen extra adjectives in genus names, before. What is the context for such name?

PMV: Usually in papers that deal with taxonomy and nomenclature, the first time that a genus or species is mentioned in text is accompanied by the authority that describes that taxon. In the case of Sturnira, it was Gray in 1842 that named the genus.

((WN)) What caused your initial interest in the question in the genus? When did you become interested?

PMV: I have been studying bats for the past eighteen years and I am especially interested in the family Phyllostomidae that is endemic to the Neotropics. This family includes more than 160 species. It is the most diverse family of bats in the Neotropics, which together exhibits more variation in morphological features and feeding ecology than any other family-level group of mammals. Phyllostomid bats exploit an unusually diverse array of feeding habits including sanguivory, insectivory, carnivory, omnivory, nectarivory, pollennivory, and frugivory. Because of all mentioned before, phyllostomids are a really interesting group to work with. Sturnira and Platyrrhinus are members of this family.

((WN)) The paper mentions that the genus is now the most speciose genus in the Neotropical family Phyllostomidae. What genus did it beat? How many species does it include?

PMV: The other genus with the most species in the family is Platyrrhinus. Currently, it has 20 species, but soon it will increase to 21. Along with another colleague, Burton Lim, we have a paper in press describing a new species based on molecular and morphological data from the Guianan Shield.

Dorsolateral views of the left mandibular toothrows in Sturnira bakeri (A, QCAZ 14635 ♀) and S. burtonlimi (B, ROM 104294 ♂), illustrating taxonomic differences in the shape of the metaconid and entoconid of m1 and m2.
Image: Paúl M. Velazco.

((WN)) What equipment did you use?

PMV: For the ZooKeys paper, we examined several specimens under the stereoscope. The molecular phylogeny gave us the separation between species, from there our job was to focus on finding morphological differences between these groups.

((WN)) Did you conduct field study to identify the species' habits? If so, where and how did you do that?

PMV: I have done fieldwork in Belize and Peru, and my coauthor did field work in Brazil, Ecuador, and Peru, where we collected several specimens of Sturnira (including the third species that has not been described yet). But the two species that were described in the ZooKeys paper are based on specimens collected by our colleagues Dr. Robert Baker from Texas Tech University and Dr. Burton Lim from the Royal Ontario Museum.

((WN)) How do you isolate of the living area of the new species from the living area of the old species?

PMV: We used the phylogeny of Velazco and Patterson 2013 (Molecular Phylogenetics and Evolution) as a framework for this.

((WN)) How long did the study take? What has been the most time-consuming activity?

PMV: It took almost a year. The most time consuming part was spending several hours behind the stereoscope looking for the diagnostic characters.

Sturnira tildae
Image: Burton K. Lim.

((WN)) Who participated in the study? What were their roles?

PMV: Dr. Bruce Patterson from the [American] Museum of Natural History and I. I was the one in charge of finding the diagnostic characters and together we both worked on the manuscript.

((WN)) Who do you collaborate with internationally about your study?

PMV: For this study I collaborated directly with Dr. Bruce Patterson from the Field Museum of Natural History, but studies like this cannot be completed without the contribution of scientific collections. We used specimens from the American Museum of Natural History, Carnegie Museum of Natural History, Louisiana State University, Museum of Southwestern Biology, Museo de Historia Natural de la Universidad Nacional de San Marcos, Museo de Zoología of the Pontificia Universidad Católica del Ecuador, Museum of Vertebrate Zoology at Berkeley, Royal Ontario Museum, Texas Tech University, and the National Museum of Natural History.

((WN)) What future research do you plan?

PMV: To keep doing what I love, which is going to the field, working at collections, and collaborating with the wonderful collaborators I have, all of this is an effort to try to understand bat diversity and evolution in the Neotropics, especially why phyllostomid bats are so successful at this. There is still much to discover, and hopefully we could, in time, implement conservation actions for species that have small distributions.

Sources

• Paúl M. Velazco, Bruce D. Patterson. "Two new species of yellow-shouldered bats, genus Sturnira Gray, 1842 (Chiroptera, Phyllostomidae) from Costa Rica, Panama and western Ecuador" — ZooKeys, April 16, 2014
• "Three new species of yellow-shouldered bats discovered in museum collections" — PhysOrg, April 14, 2014