Peptides in two Trinidadian frogs reveal antimicrobial resistance

 

Barbour's thin-toed frog (Leptodactylus insularum). Photo by Renoir Auguste

Frogs are vitally important to ecosystems, and to people. Their importance in ecosystems stems from the roles they play acting as predator and prey to a variety of animals. Their ecological importance also benefits people, as frogs prey on insects, including pests to crops and mosquitoes. However frogs also play an important role in medicinal values. In particular, the peptides in frog skin secretions have been used to treat diseases, for example diabetes. Trinidad and Tobago has at least 35 species of frogs (amphibians). Thus far, at least two frog species have shown to have peptides useful for medicine, including the paradoxical frog (Pseudis paradoxa), and the Trinidad leaf-nesting frog (Phyllomedusa trinitatis). Now, two more species can be added to the list. A recent published study by Barran and colleagues (2020) found antimicrobial resistant properties in two species. These are the Trinidadian thin-toed frog (Leptodactylus nesiotus), and Barbour's thin-toed frog (Leptodactylus insularum). Barran and colleagues' study further exemplifies the importance of conserving frogs in Trinidad and Tobago, and all citizens should do their part by learning more about them, and conserving them for generations to come. Citation: Barran, G.; Kolodziejek, J.; Coquet, L.; Leprince, J.; Jouenne, T.; Nowotny, N.; Conlon, J.M.; Mechkarska, M. Peptidomic Analysis of Skin Secretions of the Caribbean Frogs Leptodactylus insularum and Leptodactylus nesiotus (Leptodactylidae) Identifies an Ocellatin with Broad Spectrum Antimicrobial Activity. Antibiotics 2020, 9, 718. Link to paper here: pdf

Cryptic diversity, & a unique reproductive mode in a Neotropical water snake from Trinidad

A recent published study by Murphy and colleagues (2020) suggest that the number of water snakes in the genus Helicops has increased from 19 to 20 species based on morphology. Trinidad has one species (currently) in that genus - Helicops angulatus, known commonly as the brown-banded water snake, or to some locals as the "water mapepire" (seen in the photograph above by Renoir Auguste), because of its superficial resemblance to the Bothrops viper "Mapepire Balsain". This snake though, is not just another snake. It is believed to have a unique reproductive mode whereby females presumably lay eggs, like many other reptiles, but also gives birth to live young! This is sometimes referred to as facultative (viviparous) reproduction as they are able to do both. It is not certain as to what brings about the different choice (or lack thereof) in reproductive mode. Perhaps it is environmental related. However, the importance of conserving this unusual snake population, and its habitat is of paramount importance as we may be able to learn more about the evolution of this species, Squamates: lizards and snakes, and the potential benefits they may have to improving our knowledge of biodiversity conservation. Citation: Murphy JC, Muñoz-Mérida A, Auguste RJ, Lasso-Alcalá O, Rivas GA, Jowers MJ. 2020. Evidence for cryptic diversity in the Neotropical water snake, Helicops angulatus (Linnaeus, 1758) (Dipsadidae, Hydropsini), with comments on its ecology, facultative reproductive mode, and conservation. Amphibian & Reptile Conservation 14(3) [Taxonomy Section]: 138–155 (e261). Link to paper here: pdf

Brown vine snake (Horsewhip) from Trinidad and Tobago renamed after Mike Rutherford

 

The brown vine snake from Trinidad and Tobago locally known as Horsewhip has recently been re-described as a new species based on genetic and morphological data, compared to other specimens from across the Americas. The research was lead by Jadin and colleagues and published this year. The snake's scientific name is Oxybelis rutherfordi, or commonly Rutherford's vine snake.

The species has been named in honour of Mike Rutherford, who was the former Curator of the University of the West Indies Zoology Museum, for his contributions to Zoology and Natural History in Trinidad and Tobago. Persons from Trinidad and Tobago that have participated in the annual Bioblitz or with the Trinidad and Tobago Field Naturalists' Club will be familiar with Mike. Congrats, Mike!

No doubt, new species of reptiles and amphibians will continue to be described in the country, which makes for exciting opportunities for young naturalists to get involved and passionate about wildlife. 

Reference: 

Jadin et al. 2020. Not withering on the evolutionary vine: systematic revision of the Brown Vine Snake (Reptilia: Squamata: Oxybelis) from its northern distribution. Organisms Diversity & Evolution