Molecular phylogeny and historical biogeography of marine palaemonid shrimps (Palaemonidae: Palaemonella–Cuapetes group)

Abstract

Palaemonidae is the most speciose shrimp family within the infraorder Caridea, composed predominately of freshwater species and marine symbiotic species. The subject of this study is a clade of mainly free-living marine taxa representing a basally separated lineage from most of the symbiotic marine palaemonid genera. Phylogenetic and biogeographic relationships were explored by analysing sequence data from two mitochondrial and four nuclear markers. Maximum likelihood and Bayesian analyses, based on sequences from 52 species of 11 genera, provided similar tree topologies revealing the genera Palaemonella, Cuapetes and Eupontonia as non-monophyletic groups. Divergence time and S-DIVA analyses reveals that the focal clade originated during the Late Cretaceous in the Paleotethys region respective to the present Indo-West Pacific area, a minor part of which spread out to the eastern Pacific during the Paleocene, followed by further migration into the Atlantic (before the closure of the Panama Isthmus). The ancestral state reconstruction of host associations revealed eight independent symbiotic lineages originating from free-living ancestors, entering primary symbioses. The first associations with Cnidaria are estimated to have evolved in the Eocene. This study points to the need of taxonomic revisions of the non-monophyletic genera concerned.

Phylomorphometrics reveal ecomorphological convergence in pea crab carapace shapes (Brachyura, Pinnotheridae)

“…This might also be the case in other symbiotic crustacean taxa with similar evolutionary switches in their lifestyles. For example, various palaemonid shrimp lineages have evolved from having a free‐living lifestyle to a life in symbiosis with an invertebrate host (e.g., Frolová et al, 2022 ). In addition, some lineages have had multiple between‐phyla host switches, some resulting in a shift from ecto‐ to endosymbiosis (Chow et al, 2021 ; Horká et al, 2016 ).…”

Mesophotic and Bathyal Palaemonid Shrimp Diversity of the Red Sea, with the Establishment of Two New Genera and Two New Species

“…Periclimenes was, not surprisingly, recovered as a complex, polyphyletic assemblage. Similarly, Frolová et al [45] did not recover monophyletic Cuapetes Clark, 1919 and Palaemonella Dana, 1852, with several symbiotic taxa belonging to other genera, such as Vir Holthuis, 1952 and Eupontonia Bruce, 1971, embedded within these genera, whereas some free-living taxa were found in different parts of the tree. These two studies, as well as molecular analyses by Gan et al [21] and Kou et al [22,28,29], using different datasets, show that numerous taxonomic changes, including redefinitions of larger genera and descriptions of new genera, are expected in the Palaemonidae.…”

Ecomorphological convergence in the walking leg dactyli of two clades of ascidian‐ and mollusc‐associated shrimps (Decapoda: Caridea: Palaemonidae)

“…Most of these associations have evolved with fellow coral reef inhabitants, including species of the phyla Porifera, Cnidaria, Mollusca, Echinodermata and Chordata (Bruce, 1995 ; Chow et al., 2021 ; Horká et al., 2016 ). In addition, so‐called ‘inquilinistic or inquiline forms’ of palaemonid shrimps have evolved to share a burrow with pistol shrimps (Caridea: Alpheidae), opisthognath fish or echiurids (Frolová et al., 2022 ). This above‐mentioned host range is presumably an incomplete record, as many other symbiotic interactions have not been identified yet, and more associations are still being discovered (Anker & De Grave, 2021 ; de Gier & Fransen, 2018 ; Fransen et al., 2021 , 2022 ; Komai et al., 2023 ; Rauch et al., 2019 ).…”