Heterospio Ehlers 1874
- Dataset
- A new species of Heterospio (Annelida, Longosomatidae) from the Indian Ocean
- Rank
- GENUS
Classification
- kingdom
- Animalia
- phylum
- Annelida
- class
- Polychaeta
- order
- Spionida
- family
- Longosomatidae
- genus
- Heterospio
discussion
Remarks According to the relative size of anterior segments, Heterospio indica sp. nov. most closely resembles H. longissima (both the nominal species and H. longissima sensu Hartman 1965), H. catalinensis, H. peruana and H. sinica. In these species, the first elongated chaetiger is CH 9 while in H. mediterranea, H. reducta, H. angolana, Heterospio sp. A sensu Uebelacker 1984 and Heterospio sp. 1 sensu Borowski 1994, it corresponds to either CH 7 or CH 8 (see figs 5 and 6 in Parapar et al. 2014). In Heterospio indica sp. nov., H. longissima sensu Hartman 1965, H. peruana and H. sinica, CH 9 is about three times longer than any anterior segment (CH 1 – CH 8). By contrast, CH 9 is about as long as all anterior segments altogether in H. longissima Ehlers, 1874; H. catalinensis has a CH 9 which is slightly longer than CH 1 – CH 8 and bears acicular chaetae in the neuropodium of CH 1. Heterospio peruana only bears four pairs of branchiae while H. indica sp. nov., H. longissima sensu Hartman 1965 and H. sinica bear eight pairs instead. The flattened distal end of the capillary chaetae in the elongated segments in H. indica sp. nov. clearly distinguishes the new species from H. longissima sensu Hartman 1965 and H. sinica; in the former, both type of capillary chaetae are greatly different in size and shape while H. sinica bears aristate chaetae which are not found in the new species. The COI and 18 S SSU rDNA sequences from H. indica sp. nov. are publically available on GenBank and can be used as a reference for future molecular taxonomic and phylogenetic studies. They are the first DNA sequences published for any species of Longosomatidae.