ARPHA Preprints, doi: 10.3897/arphapreprints.e63082
Redescription of Gnorimosphaeroma oregonense (Dana, 1853) (Crustacea: Isopoda: Sphaeromatidae), designation of neotype, and 16S-rDNA molecular phylogeny of the north-eastern Pacific species
Regina Wetzer‡, Adam Wall‡, Niel Bruce§‡ Natural History Museum of Los Angeles County, Los Angeles, United States of America§ Museum of Tropical Queensland, Townsville, Queensland, Australia
Corresponding author: Regina Wetzer ( rwetzer@nhm.org ) © Regina Wetzer, Adam Wall, Niel Bruce. This is an open access preprint distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Citation:
Wetzer R, Wall A, Bruce N (2021) Redescription of Gnorimosphaeroma oregonense (Dana, 1853) (Crustacea: Isopoda: Sphaeromatidae), designation of neotype, and 16S-rDNA molecular phylogeny of the north-eastern Pacific species. ARPHA Preprints. https://doi.org/10.3897/arphapreprints.e63082 |  |
Abstract
Gnorimosphaeroma oregonense (Dana, 1852) is revised, a male neotype is designated, photographed, and illustrated; the species occurs from Vancouver British Columbia to the central California coast. 16S-rDNA sequences (~650 bp) for all available ethanol preserved species of Gnorimosphaeroma were used to hypothesize their relationships. Our analyses revealed a sister taxon relationship between the fully marine G. oregonense and the brackish to freshwater species, G. noblei. The oyster associated and introduced G. rayi is sister to a previously not recognized or identified, but genetically distinct, Gnorimosphaeroma sp. collected at two sites in San Francisco Bay. Gnorimosphaeroma sp. is probably also a western Pacific species based on its genetic relationship to G. rayi. Photographic comparisons are offered for G. oregonense (marine), G. noblei (freshwater), G. rayi (introduced), G. sp. (presumably introduced), and G. insulare (San Nicolas Island). Records of the holdings at the Los Angeles County Museum of Natural History are summarized. Without material available north of Vancouver through Alaska, the range of G. oregonense could not be genetically verified. This review includes a diagnosis and description of the genus Gnorimosphaeroma Menzes, 1954.
Keywords
Isopoda, Sphaeromatidae, Gnorimosphaeroma, Washington, San Francisco Bay, Tomales Bay, East Pacific, intertidal, freshwater, brackish, California