Oxygen Consumption and Ammonia Excretion of Marphysa sanguinea (Polychaeta: Eunicidae) in Relation to Body Mass and Temperature

(1) Background: Marphysa sanguinea is a polychaete with high economic value and ecological importance. Information on metabolism is important to understand the physiological action of organisms. (2) Methods: The rates of oxygen consumption (R) and ammonia excretion (U) were measured using different temperatures (T) and body mass (M) levels. The activation energy (E) was calculated using the universal temperature dependence theory. (3) Results: Oxygen consumption presented a curve with an upward trend first, and then a downward trend, and ammonia excretion displayed a “U” curve. The effects of temperature and body size on oxygen consumption and ammonia excretion rates were extremely significant. Small individuals had higher metabolic rates than large polychaetes at the same temperature. The relationship between oxygen consumption, ammonia excretion, and M was expressed as Y = a·Mb, bR = 0.56 ± 0.09, and bU = 0.35 ± 0.30. The oxygen consumption activation energy was ER = 0.68 eV, and the ammonia excretion activation energy was EU = 0.53 eV. The O:N ratio at different temperatures and body sizes was in the range of 3.55–56.44. (4) Conclusions: The results not only provide basic data on the metabolism of M. sanguinea but also insights to understand the relationship between animal metabolism and ecological factors from different perspectives.

First record of Marphysa chirigota (Annelida: Eunicidae) in the Mediterranean Sea (Gulf of Tunis)

To date, the genus Marphysa is represented by only three species, Marphysa sanguinea, Marphysa aegypti and Marphysa birgeri in the Mediterranean Sea. Combining morphological, molecular data (16S rRNA and cytochrome c oxidase subunit I mitochondrial loci) and environmental information, we are here presenting the first Mediterranean report of Marphysa chirigota, based on the specimens collected at Radès Station (Gulf of Tunis, western Mediterranean). The current information on the distribution of of the Marphysa species strongly supports that M. sanguinea inhabits hard bottoms and has a restricted distribution close to its type location (south English coast and nearby NE European Atlantic). The specimens from Radès Station, as well as all those reported as M. sanguinea along the Tunisian coast, were found in the shallow water soft bottoms. Therefore, we suggest that the presence of M. sanguinea in Tunisia seems is doubtful, and all Marphysa species reports from Tunisia might correspond to M. chirigota.

I know who you are, but do others know? Why correct scientific names are so important for the biological sciences

Researchers are continuing to identify polychaetes using inappropriate references and failing to appreciate that many if not most species have restricted distributions. Using Marphysa sanguinea (Montagu, 1813) as a case example, we discuss the loss of valuable data by misidentifying a species. We suggest ways in which this problem can be addressed by both taxonomists, ecologists and other researchers. Furthermore, this situation is not unique to polychaetes but applies to many other groups of marine invertebrates.

Morphological and molecular systematic review of Marphysa Quatrefages, 1865 (Annelida: Eunicidae) species from South Africa

A vast polychaete fauna is hidden behind complexes of cryptic and pseudo-cryptic species, which has greatly hindered our understanding of species diversity in several regions worldwide. Among the eunicids, Marphysa sanguinea Montagu, 1813 is a typical example, recorded in three oceans and with various species considered its junior synonyms. In South Africa, specimens previously misidentified as M. sanguinea are now known as Marphysa elityeni Lewis & Karageorgopoulos, 2008. Of the six Marphysa Quatrefages, 1865a species recorded from the same region, three have their distributions restricted to South Africa while the others are considered to have worldwide distributions. Here, we evaluated the taxonomic status of the indigenous M. elityeni and investigated the presence of the widespread species Marphysa macintoshi Crossland, 1903 and Marphysa depressa Schmarda, 1861 in South Africa using morphological and molecular data. Our results reveal that M. elityeni is a junior synonym of Marphysa haemasoma, a species previously described from South Africa which is herein reinstated as a valid species. Both M. macintoshi and M. depressa are not present in South Africa and their status as being distributed worldwide deserves further investigation. Marphysa durbanensis Day, 1934 and the new species described here, M. sherlockae n. sp., had been misidentified as M. macintoshi and M. depressa respectively. Thus, the number of Marphysa species with distributions restricted to South Africa increased from three to five. This study reiterates the importance of implementing an integrated taxonomic framework to unravel local biodiversity.

A new species of the sanguinea-group Quatrefages, 1866 (Annelida: Eunicidae: Marphysa) from the Philippines

A new species of the Marphysa sanguinea group, M. iloiloensis n. sp. (Annelida: Eunicida: Eunicidae), is described from the Marine Annelids Hatchery of the Southeast Asian Fisheries Development Center, Aquaculture Department (SEAFDEC- AQD), Iloilo Province, Philippines. It represents the first record of this group in the Philippines. The new species is most similar morphologically to M. hongkongensa Wang, Zhang & Qiu, 2018, but can be distinguished from it by having fewer branchial filaments, a pair of faint eyes (absent in M. hongkongensa), and in slight differences in jaw morphology and chaetation. The embryos of the new species develop inside a jelly cocoon attached to the entrance of the adult burrow; this is the first time that egg-containing cocoons have been found in any species of the sanguinea-group. Phylogenetic analysis based on the mitochondrial gene cytochrome c oxidase subunit I (COI) revealed that Marphysa iloiloensis n. sp. is genetically distinct from all other analysed Marphysa species and forms a sister group to M. hongkongensa. A revised identification key to members of the sanguinea-group in Southeast Asia is provided.

Guess who? On the importance of using appropriate name: case study of Marphysa sanguinea (Montagu, 1813)

The common bait wormMarphysasanguinea(Montagu, 1813), originally described from the south coast of England, is the type species of the genus. This species has been widely reported from all around the world and has been considered as cosmopolitan until recently. This is partly because the original description was very brief and poorly illustrated, and also because all species superficially look similar. In order to clarify the situation,M.sanguineawas redescribed and a neotype was designated by Hutchings and Karageorgpoulos in 2003. Recently, specimens from Cornwall, close to the type locality, were sampled, examined morphologically, and used to obtain COI gene sequences for this species. Molecular results permitted us to confirm the identity and presence ofM.sanguineaalong the French coasts and to highlight the presence of inaccurate sequences of this species on GenBank. Use of this “false” cosmopolitan species at a worldwide scale by many biologists is also discussed in this paper.