Two new species of Varicus from Caribbean deep reefs, with comments on the related genus Pinnichthys (Teleostei, Gobiidae, Gobiosomatini, Nes subgroup)

Tropical deep reefs (~40–300 m) are diverse ecosystems that serve as habitats for diverse communities of reef-associated fishes. Deep-reef fish communities are taxonomically and ecologically distinct from those on shallow reefs, but like those on shallow reefs, they are home to a species-rich assemblage of small, cryptobenthic reef fishes, including many species from the family Gobiidae (gobies). Here we describe two new species of deep-reef gobies, Varicus prometheus sp. nov. and V. roatanensis sp. nov., that were collected using the submersible Idabel from rariphotic reefs off the island of Roatan (Honduras) in the Caribbean. The new species are the 11th and 12th species of the genus Varicus, and their placement in the genus is supported by morphological data and molecular phylogenetic analyses. Additionally, we also collected new specimens of the closely-related genus and species Pinnichthys aimoriensis during submersible collections off the islands of Bonaire and St. Eustatius (Netherland Antilles) and included them in this study to expand the current description of that species and document its range extension from Brazil into the Caribbean. Collectively, the two new species of Varicus and new records of P. aimoriensis add to our growing knowledge of cryptobenthic fish diversity on deep reefs of the Caribbean

Extreme environmental conditions reduce coral reef fish biodiversity and productivity

Tropical ectotherms are hypothesized to be vulnerable to environmental changes, but cascading effects of organismal tolerances on the assembly and functioning of reef fish communities are largely unknown. Here, we examine differences in organismal traits, assemblage structure, and productivity of cryptobenthic reef fishes between the world’s hottest, most extreme coral reefs in the southern Arabian Gulf and the nearby, but more environmentally benign, Gulf of Oman. We show that assemblages in the Arabian Gulf are half as diverse and less than 25% as abundant as in the Gulf of Oman, despite comparable benthic composition and live coral cover. This pattern appears to be driven by energetic deficiencies caused by responses to environmental extremes and distinct prey resource availability rather than absolute thermal tolerances. As a consequence, production, transfer, and replenishment of biomass through cryptobenthic fish assemblages is greatly reduced on Earth’s hottest coral reefs. Extreme environmental conditions, as predicted for the end of the 21st century, could thus disrupt the community structure and productivity of a critical functional group, independent of live coral loss

Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences

The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & Nemésio 2007; Donegan 2008, 2009; Nemésio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on 18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based researchers who signed it in the short time span from 20 September to 6 October 2016

Patterns of evolution in gobies (Teleostei: Gobiidae): a multi-scale phylogenetic investigation

A dissertation submitted in Partial Fulfillment of the Requirements for the Degree of DOCTOR OF PHILOSOPHY in MARINE BIOLOGY from Texas A&M University-Corpus Christi in Corpus Christi, Texas.The family of fishes commonly known as gobies (Teleostei: Gobiidae) is one of the most diverse lineages of vertebrates in the world. With more than 1700 species of gobies spread among more than 200 genera, gobies are the most species-rich family of marine fishes. Gobies can be found in nearly every aquatic habitat on earth, and are often the most diverse and numerically abundant fishes in tropical and subtropical habitats, especially coral reefs. Their remarkable taxonomic, morphological and ecological diversity make them an ideal model group for studying the processes driving taxonomic and phenotypic diversification in aquatic vertebrates. Unfortunately the phylogenetic relationships of many groups of gobies are poorly resolved, obscuring our understanding of the evolution of their ecological diversity. This dissertation is a multi-scale phylogenetic study that aims to clarify phylogenetic relationships across the Gobiidae and demonstrate the utility of this family for studies of macroevolution and speciation at multiple evolutionary timescales. In the first chapter, I present a DNA sequence matrix derived from two nuclear genes to help resolve intergeneric level phylogenetic relationships with the Gobiidae. My study is the first to use data from conserved nuclear loci to infer relationships across the Gobioidei, and the results provide strong support for the monophyly of, and interrelationships between, several ecologically divergent clades. Specifically, I show that gobies are asymmetrically divided into two clades, one of which contains primarily marine species and the other comprises mostly estuarine or freshwater taxa. In the second chapter, I focus on the evolution of microhabitat association and morphology in one of the most diverse lineages of gobies, the reef-associated genus Eviota. Eviota species have invaded novel microhabitats multiple times throughout their evolutionary history, often occurring independently of diagnostic morphological changes in pectoral-fin ray branching and arrangement of sensory cephalic lateralis pores. The combination of historical ecological flexibility coupled with resilience to local extinction events may explain the elevated extant biodiversity in Eviota. Lastly, in my third chapter, I use Eviota as a model for studying fine-scale speciation in the Coral Triangle, a marine biodiversity hotspot in the Western Pacific Ocean. A phylogeographic analysis of two species complexes that have diverged within the Coral Triangle provides strong support for the hypothesis that the Coral Triangle serves as a `center of origin' or cradle of new species. Specifically, I demonstrate that a combination of biotic and abiotic factors may be contributing to rapid speciation both in allopatry and sympatry within the last 1.5 million years. The presence of recently diverged cryptic species in the Coral Triangle implies that our current estimates of biodiversity in this marine hotspot are severely underestimated. Ultimately, this dissertation demonstrates that gobies and other ecologically diverse clades of fishes serve as excellent model groups for studying the processes driving taxonomic and phenotypic diversification in marine species at a variety of spatial and temporal scales. This project will serve as a foundation for future studies that aim to use more comprehensive genomic datasets to address questions regarding drivers of speciation and ecological diversification in gobiid fishes.Life SciencesCollege of Science and Engineerin

Cerogobius petrophilus (Perciformes: Gobiidae), a new gobiid genus and species from the Red Sea

Kovačić, Marcelo, Bogorodsky, Sergey V., Troyer, Emily M., Tornabene, Luke (2019): Cerogobius petrophilus (Perciformes: Gobiidae), a new gobiid genus and species from the Red Sea. Zootaxa 4565 (2): 171-189, DOI: https://doi.org/10.11646/zootaxa.4565.2.

FIGURE 7 in Cerogobius petrophilus (Perciformes: Gobiidae), a new gobiid genus and species from the Red Sea

FIGURE 7. Suspensorium of Cerogobius petrophilus sp. nov., UW 158279. ART—articular, BR—branchiostegal ray, CHceratohyal, D—dentary, EH—epihyal, HYO—hyomandibular, IH—interhyal, MAX—maxilla, MT—metapterygoid, PALpalatine, PMX—premaxilla, POP—preopercle, PS—parasphenoid, PT—pterygoid (ectopterygoid), QU—quadrate, SYMsymplectic

Supplementary material 1 from: Fuentes KM, Baldwin CC, Robertson DR, Lardizábal CC, Tornabene L (2023) Two new species of Varicus from Caribbean deep reefs, with comments on the related genus Pinnichthys (Teleostei, Gobiidae, Gobiosomatini, Nes subgroup). ZooKeys 1180: 159-180. https://doi.org/10.3897/zookeys.1180.107551

Maximum clade credibility tree from Bayesian analysis with all sample

Alternating regimes of shallow and deep-sea diversification explain a species-richness paradox in marine fishes

The deep sea contains a surprising diversity of life, including iconic fish groups such as anglerfishes and lanternfishes. Still, >65% of marine teleost fish species are restricted to the photic zone <200 m, which comprises less than 10% of the ocean's total volume. From a macroevolutionary perspective, this paradox may be explained by three hypotheses: 1) shallow water lineages have had more time to diversify than deep-sea lineages, 2) shallow water lineages have faster rates of speciation than deep-sea lineages, or 3) shallow-to-deep sea transition rates limit deep-sea richness. Here we use phylogenetic comparative methods to test among these three non-mutually exclusive hypotheses. While we found support for all hypotheses, the disparity in species richness is better described as the uneven outcome of alternating phases that favored shallow or deep diversification over the past 200 million y. Shallow marine teleosts became incredibly diverse 100 million y ago during a period of warm temperatures and high sea level, suggesting the importance of reefs and epicontinental settings. Conversely, deep-sea colonization and speciation was favored during brief episodes when cooling temperatures increased the efficiency of the ocean's carbon pump. Finally, time-variable ecological filters limited shallow-to-deep colonization for much of teleost history, which helped maintain higher shallow richness. A pelagic lifestyle and large jaws were associated with early deep-sea colonists, while a demersal lifestyle and a tapered body plan were typical of later colonists. Therefore, we also suggest that some hallmark characteristics of deep-sea fishes evolved prior to colonizing the deep sea