Trapania orteai Garcia-Gomez & Cervera, 1989
First Mediterranean record of Trapania orteai, 30 mm
Tirrenian Sea, Sant’Agnello (NA) Italy by Fabio Russo (ScubaBiology.it)
Class: Gastropoda Cuvier, 1797
Subclass: Heterobranchia J.E. Gray, 1840
Clade: Euthyneura Spengel, 1881
Clade: Nudipleura Wägele & Willan, 2000
Order: Nudibranchia Cuvier, 1817
Suborder: Euctenidiacea Tardy, 1970
Infraorder: Doridacea Thiele, 1931
Superfamily: Onchidoridoidea J.E. Gray, 1827
Family: Goniodorididae H. Adams & A. Adams, 1854
Genus: Trapania Pruvot-Fol, 1931
Species: Trapania orteai Garcia-Gomez & Cervera in Cervera & Garcia-Gomez, 1989
Body smooth and elongated, up to 30mm long, limaciform, with the middle of the dorsum higher than the rest of the body, and a tappered posterior end. It is white in color, with generally elongated spots, reddish brown or orange, distributed more densely on the dorsum and scarcely on the flanks, but in the caudal region, which frequently has a spot (yellow in younger specimens) near the edge of the foot. It has two pairs of curved dorsal processes (which give the genus its name), usually tilted backwards and with the distal zone pigmented yellow to slightly more than half its total length (turning gradually to orange or reddish brown in adult specimens): The first pair is placed next to the rhinophores, while the second pair is placed next to the gills. The two oral tentacles, longer and thinner than the dorsal processes, are yellow throughout their length. The foot has two white tentacles in its anterior side, hook shaped and widened by their base. The rhinophores are perfoliated and have between 13 and 17 lamellae. The eyes are located right behind the rhinophores. It has three partially contractile tripinnate gills, arranged around the anus; the central gill leaf is larger (with up to 10 branches in larger specimens) and is located in a more anterior position than the lateral ones. The genital opening is located on the right side of the body, near the base of the extra-branchial process. The dark internal organs can be observed by transparency through the dorsum in the middle zone of the body.
The specimens found in the Mediterranean are usually found on sponges such as Scalarispongia scalaris (Trainito & Doneddu, 2014). It is assumed that, as in the other species of Trapania, it feeds on entoprocts, which usually grow on the surface of the porifera. The spawn consists of a white scalloped ribbon adhered to the substrate by one of its edges. The coloration of Trapania orteai is similar to that of T. maculata, although the general shape of the spots and their number varies. T. maculata usually has a large spot on each flank (not described in British specimens), which does not exist in T. orteai. T. orteai‘s propodial tentacles are white (yellow in T. maculata) and the tentaculiform palaeal processes are significantly shorter than in T. maculata. Another similar species is T. aureopunctata, but the spots on T. orteai are larger and more abundant and have a stronger orange color. In addition, in T. aureopunctata the rhinophores, oral tentacles, gills and tail are white and there are one or two spots in lateral processes.
- Trapania. Bernard Picton considers this derives from Greek drepane meaning “sickle” or “reaping hook”, presumably referred to the appendixes located in the base of rhinophores and gills in the genus Trapania.
- Orteai. Dedicated to Dr. Jesús Ortea Rato, Spanish malacologist of the Department of Zoology of the University of Oviedo, in recognition of his fruitful work in the study of the opisthobranchs.
To date it has only been observed on the Atlantic coast of the Iberian Peninsula, along the coast of the province of Cadiz and Huelva, including the Mediterranean area of Tarifa (Cervera & García Gómez, 1989), as well as in the Algarve (Gavaia et al. Al., 2003). It has been recently observed in the Bay of Naples (Italy) in which it would be the first true reports for the Mediterranean (Fabio Russo, pers., Trainito & Doneddu, 2014).
|: OBIS||: OPK|
|: GROC 2010-2011||: VIMAR|
|: Enric Madrenas||: Manuel Ballesteros.|
|: João Pedro Silva||: M@re Nostrum|
|: Bernard Picton||: Other sources|
|: GBIF.ORG||: Marine Regions|
This chart displays the observation probability for Trapania orteai
based on our own records.
Bibliography based on the works by Steve Long, 2006. Bibliography of Opisthobranchia 1554-2000 and Gary McDonald, 2009. Bibliographia Nudibranchia, with later updates from other resources.