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Geology topics

Danielle Rivera

Publications and source records attributed to Danielle Rivera.

3 recordsLinked to original sources

High-quality, chromosome-level reference genomes of the viviparous Caribbean skinks Spondylurus nitidus and S. culebrae

New World mabuyine skinks are a diverse radiation of morphologically cryptic lizards with unique reproductive biologies. Recent studies examining population-level data (morphological, ecological, and genomic) have uncovered novel biodiversity and phenotypes, including the description of dozens of new species and insights into the evolution of their highly complex placental structures. Beyond the potential for this diverse group to serve as a model for the evolution of viviparity in lizards, much of the taxonomic diversity is concentrated in regions experiencing increasing environmental instability from climate and anthropogenic change. Consequently, a better understanding of genome structure and diversity will be an important tool in the adaptive management and conservation of this group. Skinks endemic to Caribbean islands are particularly vulnerable to global change with several species already considered likely extinct and several remaining species either endangered or threatened. Combining PacBio long-read sequencing, Hi-C, and RNAseq data, here we present the first genomic resources for this group by describing new chromosome-level reference genomes for the Puerto Rican Skink Spondylurus nitidus and the Culebra Skink S. culebrae . Results indicate two high quality genomes, both ∼1.4 Gb, assembled nearly telomere to telomere with complete mitochondrion assembly and annotation.

Genome Biology and Evolution

Multiple records of the introduced parthenogenetic Smooth-scaled Tegulet, Gymnophthalmus underwoodi Grant 1958, in Puerto Rico

The introduction of invasive species to islands can be devastating to local biota. While many invasive species’ successful colonization of new habitats can be attributed to features like high fecundity or low mate selectivity, parthenogenetic species pose a unique threat in their ability to reproduce asexually at high rates. The Smooth-scaled Tegulet ( Gymnophthalmus underwoodi ), first described from Barbados in the 1950s, has since been documented as an introduced species across additional Lesser and Greater Antillean islands as well as northwestern Brazil and Venezuela. Herein we report multiple individuals from Puerto Rico, including the first genetic records, which indicate that the individuals on this island are most closely related to populations recorded from Brazil and Montserrat. Additional genetic information is necessary to determine the timing and migration of this species across the Caribbean. Regardless, the continued geographic expansion of this parthenogen across the Caribbean could present a threat to local fauna.

Reptiles and Amphibians