Island biogeography and ecological modeling of the amblypygid Phrynus marginemaculatus in the Florida Keys archipelago

Abstract

AimThe biogeography of terrestrial organisms across the Florida Keys archipelago is poorly understood. We used population genetics and spatioecological modeling of the Amblypygi Phrynus marginemaculatus to understand the genetic structure and metapopulation dynamics of Keys populations that are otherwise isolated by human development and ocean.LocationThe Florida Keys archipelago and mainland Florida.MethodsWe sequenced a 1,238 bp fragment of mtDNA for 103 individuals of P. marginemaculatus from 13 sites in the Florida Keys and South Florida, binned into four regions. We used population genetic analyses to understand the population structure of the species throughout its US range. Furthermore, we used ecological modeling with climate, habitat, and human development data to develop habitat suitability estimates for the species.ResultsWe found clear genetic structure between localities. The Lower Keys, in particular, support populations separate from those in other regions studied. Ecological modeling and genetic analyses showed the highest habitat suitability and genetic isolation in the Lower Keys, but urban development across the species range has resulted in the loss of most historical habitat.Main conclusionsA mainland‐metapopulation model best fits P. marginemaculatus gene flow patterns in the Florida Keys and mainland. Ocean currents likely play a role in metapopulation dynamics and gene flow for terrestrial Keys species like P. marginemaculatus, and genetic patterns also matched patterns consistent with geologic history. Suitable habitat, however, is limited and under threat of human destruction. The few remaining pockets of the most suitable habitat tend to occur in parks and protected areas. We argue that conservation efforts for this species and others in the terrestrial Florida Keys would benefit from a deeper understanding of the population genetic structure and ecology of the archipelago.

Deep mtDNA Sequence Divergences and Possible Species Radiation of Whip Spiders (Arachnida, Amblypygi, Phrynidae, Phrynus/Paraphrynus) among Caribbean Oceanic and Cave Islands

“…Geographical distance is the obvious explanation for genetic divergences (see also [67]). For example, only two species were both found on the mainland (Florida) and on an island.…”

Volcanism and palaeoclimate change drive diversification of the world's largest whip spider (Amblypygi)

“…DNA extraction, PCR (polymerase chain reaction) and Sanger dideoxy sequencing were performed at the AMNH Sackler Institute of Comparative Genomics (SICG), using standard protocols (Prendini et al, 2005). Three nuclear gene markers, 18S rDNA (18S), 28S rDNA (28S), and a region spanning the Internal Transcribed Spacer 1, 5.8S rDNA and Internal Transcribed Spacer 2 (ITS1/2), and three mitochondrial gene markers, 12S rDNA (12S), 16S rDNA (16S) and cytochrome c oxidase subunit I (COI), were selected for efficacy in reconstructing the phylogeny of whip spiders (Chapin et al, 2018; Esposito et al, 2015; Harrison et al, 2017; Prendini et al, 2005). Loci were amplified using universal primers and/or, in the case of COI, 28S and ITS1/2, with primers specifically designed for Acanthophrynus (Tables ).…”

“…Whip spiders (Amblypygi Thorell, 1883), an order of tropical arachnids related to spiders (Weygoldt, 2000), which reach their greatest diversity in the Mexican Neotropics (Armas, 2006; Harvey, 2003), offer a model system to address the drivers of tropical diversification. Unlike spiders, most of which are capable of dispersal on air currents (Weyman, 1993), whip spiders are limited to walking and possibly rafting (Chapin et al, 2018). Their vagility is further constrained by an ecological requirement for humidity, which restricts them to forests, caves or the vicinity of permanent water sources in arid areas (Weygoldt, 2000).…”

“…Their vagility is further constrained by an ecological requirement for humidity, which restricts them to forests, caves or the vicinity of permanent water sources in arid areas (Weygoldt, 2000). Although phylogeographical studies of whip spiders remain scarce, the few published to date confirm that their diversity is underestimated and informative for understanding diversification in the tropics (Chapin et al, 2018; Esposito et al, 2015; Prendini et al, 2005; Reveillion et al, 2020).…”

Ecological niche modeling in a whip spider, Heterophrynus boterorum (Phrynidae), from the Colombian Central Andes

“…We used the species H. boterorum as a model to understand how much wider the distribution of an endemic Heterophrynus species could be, and how much of this potential distribution is part of an already established protected area. At the moment, only a paper about the potential distribution of species of Phrynidae has been published, however, it refers to a species of Phrynus from the Caribbean Islands (Chapin et al, 2018).…”