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Abstract Across plants and animals, genome size is often correlated with life‐history traits: large genomes are correlated with larger seeds, slower development, larger body size and slower cell division. Among decapod crustaceans, caridean shrimps are among the most variable both in terms of genome size variation and life‐history characteristics such as larval development mode and egg size, but the extent to which these traits are associated in a phylogenetic context is largely unknown. In this study, we examine correlations among egg size, larval development and genome size in two different genera of snapping shrimp,AlpheusandSynalpheus, using phylogenetically informed analyses. In bothAlpheusandSynalpheus, egg size is strongly linked to larval development mode: species with abbreviated development had significantly larger eggs than species with extended larval development. We produced the first comprehensive dataset of genome size inAlpheus(n = 37 species) and demonstrated that genome size was strongly and positively correlated with egg size in bothAlpheusandSynalpheus. Correlated trait evolution analyses showed that inAlpheus, changes in genome size were clearly dependent on egg size. InSynalpheus, evolutionary path analyses suggest that changes in development mode (from extended to abbreviated) drove increases in egg volume; larger eggs, in turn, resulted in larger genomes. These data suggest that variation in reproductive traits may underpin the high degree of variation in genome size seen in a wide variety of caridean shrimp groups more generally.
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Application of integrative taxonomy combining phylogenetic and geometric morphometric techniques in a snapping shrimp ( Alpheus ) species complex (Decapoda: Caridea: Alpheidae)
Abstract Snapping shrimps of the genus Alpheus Fabricius, 1798 exhibit remarkable diversity, with over 300 described species. The genus is well-known for its prevalence of species complexes, necessitating the need of new tools to facilitate species discrimination. Traditional taxonomic methods in Alpheus have primarily relied on the examination of morphological traits or comparative morphometric measurements, with an emphasis on variation in the major chela and rostro-orbital region. We applied an integrated approach that combines molecular genetics and geometric morphometrics to investigate the A. gracilipesStimpson, 1860 species complex. We additionally applied geometric morphometric techniques to study the major chela and the rostrum across different species, and used three mitochondrial genes (12S, COI, and 16S) to reconstruct phylogenetic relationships of this complex. Our results demonstrate the first application of geometric morphometric techniques to Alpheus snapping shrimps, and highlight the significance of the major chela and rostrum as taxonomically informative traits. Furthermore, we use DNA barcodes and geometric morphometric techniques to the A. gracilipes species complex to reveal two previously unidentified cryptic species. We present the first phylogenetic reconstruction of this species complex, with new localities and expanded distribution ranges reported for many species.
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- Award ID(s):
- 1924675
- PAR ID:
- 10558986
- Publisher / Repository:
- Journal of Crustacean Biology
- Date Published:
- Journal Name:
- Journal of Crustacean Biology
- Volume:
- 43
- Issue:
- 4
- ISSN:
- 0278-0372
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1093/jcbiol/ruad078
