Orbiniella Day 1954
Description
Genus Orbiniella Day, 1954
Type species. Orbiniella minuta Day, 1954
Orbiniella Day, 1954: 22, Fig. 3 G–K.
Falklandiella.— Hartman 1967: 109, Fig. 35.
Orbiniella.— Fauchald 1977: 16; Solís-Weiss & Fauchald 1989: 781; Buzhinskaja 1993: 77, Figs. 1–3; Gillet 1999: 592, Figs. 1–2.
Diagnosis. Body not divided into thorax and abdomen, prostomium rounded. Eyes present or absent. Two peristomial annuli. Chaetigerous segments without branchiae or parapodial lobes; chaetae including crenulated capillaries and simple acicular spines. Noto- and neuropodial capillaries either smooth, with two rows of wide teeth along the margins, or with transverse rows of short spines. Teeth sometimes bearing long hairs at distal tips. Short and thick acicular spines (smooth or barbed) maybe present in both parapodial rami or only in neuropodia. Pygidium with two or four lobes, with or without cirri.
Remarks. Originally, Day (1954) did not provide a diagnosis of the genus Orbiniella, which is later provided by Fauchald (1977) and more recently by Solís-Weiss & Fauchald (1989), Buzhinskaja (1993) and Gillet (1999). The diagnosis followed here is that proposed by Buzhinskaja (1993), which has been slightly modified to avoid ambiguous terms such as “first two segments”; those refer to the two achaetous anterior rings. Furthermore, we consider that the pygidium may be either bilobed (as referred for previously described species) or four-lobed (the new species described herein).
There has also been confusion over the location of the peristomium and first segment in the Orbiniidae in general (Rouse 2002) and in Orbiniella in particular. Thus, genera of the Microrbiniinae Blake, 2000 have two annuli between the prostomium and the first chaetiger. Some authors consider that one of them is an “achaetous segment” (Day 1977; Fauchald 1977; Solís-Weiss & Fauchald 1989); alternatively, the peristomium would be constituted by two rings (Blake 1996). We consider that the latter would be more plausible; however, using the number of peristomial rings for separating genera or species may be not a reliable character (Blake 2000). Furthermore, the division of body into thorax and abdomen through transitional segments and presence of furcate chaetae does not seem appropriate to characterize the genus Orbiniella (Buzhinskaja 1993) and therefore O. drakei should not be included in this genus. Likewise, the presence of branchiae in O. branchiata suggests that this species should be referred to other genus (Blake 2000). Buzhinskaja (1993) also suggests that Falklandiella annulata should be transferred to Orbiniella, according to the original description and drawings by Hartman (1967). Blake (2000) considers it as valid although Fauchald (1977) places this genus as incertidae sedis but still recognising that resembles the orbiniids in chaetal features.
Notes
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Linked records
Additional details
Identifiers
Biodiversity
- Family
- Orbiniidae
- Genus
- Orbiniella
- Kingdom
- Animalia
- Phylum
- Annelida
- Scientific name authorship
- Day
- Taxon rank
- genus
- Taxonomic concept label
- Orbiniella Day, 1954 sec. Parapar, Moreira & Helgason, 2015
References
- Day, J. H. (1954) The Polychaeta of Tristan da Cunha. Results of the Norwegian Scientific Expedition to Tristan da Cunha, 1937 - 1938, 29, 1 - 35.
- Hartman, O. (1967) Polychaetous annelids collected by the USNS Eltanin and Staten Island cruises, chiefly from Antarctic Seas. Allan Hancock Monographs in Marine Biology, 2, 1 - 387. http: // dx. doi. org / 10.1086 / 405769
- Fauchald, K. (1977) The Polychaete worms. Definitions and keys to the Orders Families and Genera. Natural History Museum of Los Angeles County, Science Series, 28, 1 - 188.
- Solis-Weiss, V. & Fauchald, K. (1989) Orbiniidae (Annelida: Polychaeta) from mangrove root-mats in Belize, with a revision of Protoariciin genera. Proceedings of the Biological Society of Washington, 102, 772 - 792.
- Buzhinskaja, G. N. (1993) [Occurrence of Orbiniella plumisetosa sp. n. (Polychaeta: Orbiniidae) in the north-western Pacific Ocean and a key to species of the genus Orbiniella]. Explorations of the Fauna of the Seas, 43, 76 - 81. [in Russian]
- Gillet, P. (1999) A new species of Orbiniella (Orbiniidae: Polychaeta) from Marion Island, Indian Ocean. Proceedings of the Biological Society of Washington, 112, 592 - 597.
- Rouse, G. W. (2002) Orbiniidae. In: Rouse, G. W. & Pleijel, F. (Eds.), Polychaetes. Oxford University Press, Oxford, pp. 57 - 60.
- Blake, J. A. (2000) A new genus and species of polychaete worm (Family Orbiniidae) from methane seeps in the Gulf of Mexico, with a review of the systematics and phylogenetic relationships of the genera of Orbiniidae. Cahiers de Biologie Marine, 41, 435 - 449.
- Day, J. H. (1977) A review of the Australian and New Zealand Orbiniidae (Annelida: Polychaeta). In: Reish, D. J. & Fauchald, K. (Eds.), Essays on Polychaetous Annelids in memory of Dr. Olga Hartman. Allan Hancock Foundation, University of Southern California, pp. 217 - 246.
- Blake, J. A. (1996) Family Orbiniidae Hartman, 1942. In: Blake, J. A., Hilbig, B. & Scott, P. H. (Eds.), Taxonomic Atlas of the benthic fauna of the Santa Maria Basin and western Santa Barbara Channel. Vol. 6. The Annelida Part 3. Polychaeta: Orbiniidae to Cossuridae. Santa Barbara Museum of Natural History, California, pp. 1 - 26.