Cristobó, 2002
Species Overview
Tedania (Tedania) urgorri Cristobó (2002) has characteristic external crateriform appearance with its lateral wall from 2 to 7 cm in height, thickness decreasing from the base to the upper border. Stelliform ostia on the external face of the crater and oscula of 1 mm in diameter in the wide atrium. Skeleton composed of reticulated tracts of choanosomal styles and ectosomal stylotornotes arranged in a palisade and bouquets. The microscleres are onychaetes of two size classes. Orange in colour.
Taxonomic Description
Colour: Orange.
Shape, size, surface and consistency: Massive, crateriform, with irregular bases but with a tendency to be circular or elliptical. Large open atrium, ovoid or circular in form. Cuneiform lateral walls from 2 to 7 cm in height, thickness decreasing from the base (15 mm) to the upper border (2 mm). Sometimes several craters of different sizes can be seen, anastomosed at their bases. Stelliform ostia on the external face (inhalant) of the crater where swollen areas of the wall may lead to increased solidity of the sponge. Oscula of 1 mm in diameter easily visible in the wide atrium. Even, smooth and velvety surface. Consistency in vivo slightly compressible, but fragile in alcohol.
Spicules: Megascleres: Styles entirely smooth, strong, slightly curved. Isodiametric choanosomal with evenly rounded bases without tyles and with a hastate point, 220.6-416.9 x 4.3-11.4 µm. Stylotornotes smooth, straight or slightly curved ectosomal, isodiametric in the shaft and unequal swelling at each end, one with rounded tylote or subtylote bases and the other with mucronate or arrow-like pointed end that in SEM micrographs shows a nipple-like point, 166.6-333.9 x 2.8-8.9 µm. Microscleres: Onychaetes, clearly differentiated into two size categories: I, 193-272 x 0.7-2.5 µm and II, 58-130 x 0.3-1.1 µm. Small onychaetes are straight, entirely spined with spines directed towards the same apex. Unequal ends. Onychaetes I are straight or slightly curved and entirely spined.
Skeleton: Typical of the genus. The choanosomal skeleton consists of paucispicular tracts of 10-20 styles without differences in the primary and secondary ones, from the base to the surface. Plumoreticulate appearance. Ectosomal skeleton multispicular with a continuous palisade of stylotornotes in brushes or bouquets perpendicular to the surface. Onychaetes of two size classes in the ectosome and choanosome.
Distribution: So far known only from Galicia, NW Spain.
Ecology: The specimens were collected on a rocky bottom of granite at depths of 37-45 m. It lives on vertical or inclined walls and often on horizontal areas of granitic rocks.
Etymology: Named after the malacologist Dr Victoriano Urgorri Carrasco from Ferrol.
Type specimen information: Holotype: Museo Nacional de Ciencias Naturales of Madrid N° MNCN 1.01/186, from As Merloeiras (43°26'24"N 08°19' 4"W) 37.5 m, 17 August 1991.
Remarks
T. urgorrii is most similar, with respect to external aspect, to T. infundibuliformis Ridley & Dendy, 1887, although it is easy to establish clear differences in its habitus, colour, size and form of the spicules. The sympatric T. pillariosae is similar in spiculation, but differs clearly in habit.
Source: Cristobó, 2002. |
