Paralophaster Fisher 1940
Paralophaster versus Lophaster Mah & Foltz (2011b) included three Paralophaster species, P. antarcticus , P. godfroyi , and P. lorioli in their molecular phylogenetic overview of the Valvatida. Although these three species clustered together on both two-gene and three-gene trees, as part of a si...
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| Format: | Other/Unknown Material |
| Language: | unknown |
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Zenodo
2023
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| Online Access: | https://doi.org/10.5281/zenodo.8092150 http://treatment.plazi.org/id/03C387E86606FFDBFF68E538838EF965 |
| Summary: | Paralophaster versus Lophaster Mah & Foltz (2011b) included three Paralophaster species, P. antarcticus , P. godfroyi , and P. lorioli in their molecular phylogenetic overview of the Valvatida. Although these three species clustered together on both two-gene and three-gene trees, as part of a single lineage, Lophaster densus was also supported. This has resulted in further study of the diagnostic characters that separate Lophaster and Paralophaster. Lophaster has been historically characterized by the possession of distinct, more elongate, and larger marginal paxillae (i.e., marginal plates that are paxillae-like in shape), especially the superomarginal paxillae, which are clearly distinguished from the abactinal paxillae in Lophaster . This is contrasted with Paralophaster that was originally characterized by Fisher (1940: 175) as simply having “undifferentiated” superomarginals but has undergone redefinition to being similar in size or more precisely as being “…hardly if at all, larger than the abactinal paxillae” (e.g.,A.M. Clark 1962: 80). Fisher (1940) also described the genus Myoraster to accommodate Lophaster antarcticus which he argued was distinctive based on actinolateral muscle bands, in comparison to Lophaster densus which was lacking Myoraster ’s muscle bands. A.M. Clark (1962) synonymized the genus Myoraster transferring Lophaster antarcticus to Paralophaster. Paralophaster has been reported from further occurrence (e.g., Presler & Figielska 1997) and environmental accounts (e.g., McClintock et al . 2011) with no further taxonomic/systematic overviews other than the recently described Paralophaster from deep-sea North Pacific settings near Japan (Mah & Fujita 2020). Phylogenetic analysis of the Valvatacea (Mah & Foltz 2011b), included three Paralophaster species, P. godfroyi, P. lorioli , and P. antarcticus as well as the Antarctic Lophaster densus. All four taxa were supported on a single clade, supporting the Solasteridae, by two-gene and three-gene trees. The key diagnostic ... |
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