Vertical structure of Caribbean deep-reef fishes from the altiphotic to deep-sea boundary.

While recent technical breakthroughs have enabled advances in the description of reefs down to 150 m, the structure and depth zonation of deep-reef communities below 150 m remains largely unknown. Here, we present results from over 10 years of deep-reef fish surveys using human-occupied submersibles at four locations across the Caribbean Sea, constituting one of the only continuous reef-fish surveys from 10 to 480 m (1 site) and 40 to 300 m (3 sites). We identify four vertically stratified deep-reef fish communities between 40 and 300 m bordered by an altiphotic (0-10 m) and a deep-sea (300-480 m) community. We found a strong faunal break around 150 m that separates mesophotic and rariphotic zones and secondary breaks at ~ 70 to 90 m and ~ 180 to 200 m subdividing these zones into upper and lower communities. From 300 to 480 m in Roatán, we found a single fish community dominated by deep-sea families, indicating that the lower boundary of the reef-fish realm occurs at 300 m. No differences were found between communities ranging from 20 to 60 m, suggesting that fishes from the lower altiphotic and upper mesophotic form an ecological continuum. While some variability was observed across sites, the overall depth zonation and key species characterizing depth zones were consistent. Most deep-reef species observed were depth specialists restricted to a single depth zone, but many shallow-reef species extended down to mesophotic depths. Depth segregation among species of a genus was found across ten reef-fish genera and likely constitutes one of the mechanisms driving community distinctiveness and thereby fish diversity across depths.

Life experience pathways to college student emotional and mental health: A structural equation model.

Objective: Previous research suggests that both adverse childhood experiences (ACEs), positive childhood experiences (PCEs), and current life experiences are associated with emotional wellbeing and mental health. The purpose of this study was to explore the influence of these life experience and coping processes on college student emotional and mental health. Participants: College students (N = 555) were recruited from a large western university. Methods: Participants completed an online cross-sectional survey measuring early and current life experiences, cognitive and emotional coping efforts, and emotional and mental health outcomes. Data were analyzed using structural equation modeling. Results: There was an indirect effect of PCEs on emotional and mental health through cognitive and emotional coping efforts. No association was observed between ACEs and mental health. Conclusions: Increases in PCEs are protective, enhance coping efforts, and strengthen emotional and mental health outcomes among college students.

Corrigenda: A new species of Chromis damselfish from the tropical western Atlantic (Teleostei, Pomacentridae). ZooKeys 1008: 107-138. https://zookeys.pensoft.net/article/58805/.

[This corrects the article DOI: 10.3897/zookeys.1008.58805.].

A new species of Chromis damselfish from the tropical western Atlantic (Teleostei, Pomacentridae).

Initially described in 1882, Chromis enchrysurus, the Yellowtail Reeffish, was redescribed in 1982 to account for an observed color morph that possesses a white tail instead of a yellow one, but morphological and geographic boundaries between the two color morphs were not well understood. Taking advantage of newly collected material from submersible studies of deep reefs and photographs from rebreather dives, this study sought to determine whether the white-tailed Chromis is actually a color morph of Chromis enchrysurus or a distinct species. Phylogenetic analyses of mitochondrial genes cytochrome b and cytochrome c oxidase subunit I separated Chromis enchrysurus and the white-tailed Chromis into two reciprocally monophyletic clades. A principal component analysis based on 27 morphological characters separated the two groups into clusters that correspond with caudal-fin coloration, which was either known or presumed based on the specimen's collection site according to biogeographic data on species boundaries in the Greater Caribbean. Genetic, morphological, and biogeographic data all indicate that the white-tailed Chromis is a distinct species, herein described as Chromis vanbebberae sp. nov. The discovery of a new species within a conspicuous group such as damselfishes in a well-studied region of the world highlights the importance of deep-reef exploration in documenting undiscovered biodiversity.