Calderon-Acevedo, C. A. | bioRxiv Science

bioRxiv2022

Biogeography and Validation of species limits in Caribbean Red Bats (Vespertilionidae: Lasiurus)

AO_SCPLOWBSTRACTC_SCPLOWDefining species limits using an integrative framework is crucial for biodiversity assessments and to maintain taxonomic stability. These approaches are robust and can be useful to also validate the status of species that are uncommon and underrepresented in biological collections. We examined the species limits and validated the taxonomic status of the Minor Red Bat (Lasiurus minor), an uncommon species originally described from four specimens. Our approach consisted of three independent lines of evidence combining genetic and phenotypic data. Phylogenetic analyses confirmed the uniqueness of L. minor compared to three other geographically and closely related Red Bat species. Furthermore, coalescent species delimitation supported the four Red Bat species hypothesis. Linear phenotypic analyses demonstrated that L. minor is distinct from other Red Bats despite a morphological continuum. Finally, we reassessed the diagnosability of characters used to describe L. minor using an objective shape analysis approach, which emphasized the support for this taxon. Based on our findings, while identification in the field could still pose a challenge, there is strong support to recognize L. minor. This study settles a longstanding taxonomic question and provides evidence to better understand Caribbean biodiversity.

zoology↗

bioRxiv2020

Effect of land use, habitat suitability, and hurricanes on the population connectivity of an endemic insular bat

Habitat loss and fragmentation are a leading cause of vertebrate population declines and extinction. Urbanization and natural disasters disrupt landscape connectivity, effectively isolating populations and increasing the risk of local extirpation particularly in island systems. Puerto Rico, one of the most isolated islands in the Caribbean, is home to 13 bat species that have been differentially affected by disturbance during the Anthropocene. We used circuit theory to model the landscape connectivity within Puerto Rico with the goal of understanding how fragmentation affects corridors among forested areas. Models combined species occurrences, land use, habitat suitability, and vegetation cover data to examine connectivity in the endemic bat Stenoderma rufum, and also at the bat community level across the island. Urbanization in Puerto Rico affected bat connectivity overall from east to west and underscored protected and rustic areas for the maintenance of forest corridors. Suitable habitat provided a reliable measure of connectivity among potential movement corridors that connected more isolated areas. We found that intense hurricanes can disrupt forest integrity and affect connectivity of suitable habitat. Some of the largest protected areas in the east of Puerto Rico are at an increasing risk of becoming disconnected from more continuous forest patches. The disruption of corridors that maintain connectivity on the island could explain previous findings of the slow post-hurricane population recovery of S. rufum. Given the increasing rate of urbanization, this pattern could also apply to other vertebrates not analyzed in this study. Our findings show the importance of maintaining forest integrity, emphasizing the considerable conservation value of rustic areas for the preservation of local biodiversity.

ecology↗

bioRxiv2018

Large Anoura (Chiroptera:Glossophaginae) taxonomy, taxonomic status of Anoura carishina, and implications for the distribution of Anoura latidens in Colombia.

The Anoura geoffroyi species complex is composed of 3 large species: A. geoffroyi, A. peruana, and A. carishina. Several inconsistencies arise from the description of A. carishina, and given the lack of a comparison with the dentition and external characters of A. latidens, here we compare the taxonomic characters of these species. To understand the position of A. carishina in the morphospace occupied by large Anoura, we conducted a Principal Component Analysis on 12 craniodental and 11 external variables. We complement our results with further analysis of traits thought to be diagnostic for these species, including 1) an elliptical Fourier transformation analysis of the shape of the third upper premolar (P4), 2) a comparison of the area of the second (P3) and third (P4) upper premolars, and 3) a comparison of maxillary toothrow angles. We find that A. carishina is morphologically indistinguishable from A. latidens, and that there is broad overlap in morphology between A. latidens and A. geoffroyi. However several characters found in A. latidens are lacking in A. geoffroyi, including a triangular shape to the P4 caused by a medial-internal cusp enclosed by the base of the tooth, a lack of development of the anterobasal cusp in the P3, a smaller braincase, and a shorter rostrum. We reassess the distribution of Anoura latidens in Colombia, adding new records and correcting previously-published records that were misidentified. Overall, our results suggest that a stable taxonomy for the group should consider A. carishina as a junior synonym of A. latidens, and that, although A. latidens is distinguishable from A. geoffroyi, further genetic and taxonomic work is needed in to clarify species limits within the A. geoffroyi species complex.\n\nEl complejo de especies Anoura geoffroyi se compone de 3 especies, A. geoffroyi, A. peruana, y A. carishina. La descripcion de Anoura carishina posee varias inconsistencias, y dado que no se realizo una comparacion con A. latidens, realizamos una comparacion de los caracteres taxonomicos de ambas especies. Para entender la posicion de A. carishina en el morfoespacio ocupado por los Anoura grandes realizamos un Analisis de Componentes Principales usando 12 variables craneo-dentales y 11 variables externas. Complementamos nuestros resultados con 1) un analisis de transformacion eliptica de Fourier de la forma del tercer premolar superior (P4) 2) una comparacion del area del segundo (P3) y tercer (P4) premolares superiores y 3) una comparacion de los angulos de las hileras dentales maxilares. Encontramos que A. carishina es morfologicamente indistinguible de A. latidens y que existe una amplio superposicion en la morfologia de A. latidens y A. geoffroyi. Sin embargo, la forma del P4, una cuspide anterobasal no desarrollada en el P3, y caracteres relacionados con una caja craneana menos inflada y un rostro corto son utiles en distinguir A. latidens de A. geoffroyi. Reevaluamos la distribucion de Anoura latidens en Colombia, al agregar nuevos registros y corrigiendo registros previamente publicados que se encontraban mal identificados. En general, nuestros resultados sugieren que una taxonomia estable para el grupo deberia considerar a A. carishina como un sinonimo junior de A. latidens, que A. latidens es distinguible de A. geoffroyi utilizando medidas craneo-dentales y resalta la necesidad de estudios geneticos para esclarecer las relaciones filogeneticas entre A. latidens y el complejo de especies A. geoffroyi.

zoology↗