A new species of Polygordius (Polychaeta: Polygordiidae): from the inner continental shelf and in bays and harbours of the north-eastern United States

Abstract

A new species of Polygordiidae, Polygordius jouinae sp. nov., along with its distribution, habitat, and reproduction is described. Polygordius jouinae sp. nov., the first North American Polygordius, is a dominant member of macrofaunal communities on the inner continental shelf, and in bays and harbours from Massachusetts to southern New Jersey. It is distinguished from most other Polygordius species by its non-inflated, heavily ciliated pygidium, absence of pygidial glands, and a conical (rather than rounded) prostomium. The 18S SSU rDNA from P. jouinae sp. nov. was sequenced and represents the first named Polygordius species with a DNA reference in GenBank. Spearman rank correlation of sediment grain size with density of P. jouinae sp. nov. at a New Jersey site showed that density was significantly (P<0.05; N=92) positively correlated with the proportion of medium to very coarse sand and negatively correlated with the fine sand fractions. Ecologically, P. jouinae sp. nov. is an important macrofaunal species given its widespread distribution and its fidelity for coarse sand habitats. Thus, its relative abundance may be useful as an indicator of changing sedimentary conditions.

Cellular Identity of a Novel Small Subunit rDNA Sequence Clade of Apicomplexans: Description of the Marine Parasite Rhytidocystis polygordiae n. sp. (Host: Polygordius sp., Polychaeta)

“…were isolated from the intestinal epithelium of the polychaete Polygordius sp. Ramey, 2006. Host worms were collected during the spring and summer months of 2004/05 by SCU-BA divers near Station 9 at the LEO-15 research site on Beach Haven Ridge, NJ (39128 0 N, 74115 0 W) (Ramey et al 2006;Von Alt and Grassle 1992).…”

“…Rhytidocystis comprises three species, all of which were collected from polychaetes in European waters of the eastern Atlantic Ocean (de Beauchamp 1913;Porchet-Hennere 1972). Here we describe a new rhytidocystid species that parasitizes Polygordius, a meiofaunal polychaete from North American waters of the western Atlantic Ocean (Ramey, Fiege, and Leander 2006). Our ultrastructural and molecular phylogenetic data help clarify the cellular identity of Rhytidocystis, and a poorly understood parasite of the giant clam Tridacna crocea.…”

More Knot Worms: Four New Polygordius (Annelida) Species from the Pacific and Caribbean

“…Their long, cylindrical bodies appear relatively similar to one another under visual inspection, and the distinguishing features useful for morphology-based discrimination of species are small, requiring examination under scanning electron microscopy [3]. Even annelid species with larger and more conspicuous external features may be difficult to describe based on morphological methods alone [11], and species richness and diversity within Annelida in general and Polygordius specifically are likely much greater than is presently documented due to such challenges [10,12]. Molecular data can reveal both synonymous and cryptic species [5] and, combined with morphology-based techniques, provides a powerful tool for delineating species with greater accuracy.…”

New Polygordiidae (Polychaeta) from the Australian region

“…Polygordiidae, however, have not previously been recorded from Australian waters (Paxton, 2000), although they are known from elsewhere in the Pacific region: New Caledonia (Jouin, 1970), Japan (Izuka, 1903;Uchida, 1935) and the Galapagos (Schmidt & Westheide, 1977). The Polygordiidae comprises a single genus, Polygordius, with 16 species (Ramey et al, 2006). A second genus, Chaetogordius, for Chaetogordius canaliculatus Moore, 1904 is based on fragments and is regarded as an invalid taxon (Rota & Carchini, 1999;Westheide, 1990).…”

“…More complete descriptions of the family are Rouse & Pleijel (2001) and Glasby & Fauchald, 2002). The most current taxonomic reviews of species of Polygordiidae are Rota and Carchini (1999) and Ramey et al (2006).…”