(Haeckel, 1870)
Species Overview
Amphoriscus oviparus (Haeckel, 1870) is a stalked tubular brownish white calcareous sponge, originally described from Florida but reported from deeper water in the Roscoff area and off Plymouth. The tubes are rather smooth and apparently do not have a fringe of longer spicules around the apical oscule. The status of this species is uncertain.
Taxonomic Description
Colour: In life unknown, but in alcohol it is brownish.
Shape, size, surface and consistency: Stalked, thin tubes of a few cm in length. Surface smooth, even, non-hispid. Apical oscule not provided with a fringe of longer spicules. Consistency unknown.
Spicules: Calcareous. Triactines and tetractines.
Triactines sagittal, in a single category, found only in the ectosome: basal ray 300-500 x 10-25 µm and paired rays 200-400 x 10-25 µm.
Tetractines in three categories: (1) sagittal subectosomal with basal ray 600-800 x 40-60 µm, paired rays 400-600 x 40-60 µm and apical ray 800-1200 x 40-60 µm; (2) sagittal subchoanosomal with basal ray 500-600 x 20-30 µm, paired rays 200-300 x 20-30 µm, and apical ray 200-300 x 20-30 µm; (3) equal-rayed gastral tetractines with rays of the basal triactine system 200-300 x 20-30 µm and apical ray 30-60 x 20-30 µm.
Skeleton: No articulate choanosomal skeleton. Choanosomal chambers are supported by the basal rays of subectosomal and subchoanosomal tetractines. The ectosomal skeleton consists of a tangential layer of triactines, supported by the paired rays of the subectosomal tetractines. Gastral cavity lined by several layers of equal-rayed tetractines.
Reproduction: July-August.
Ecology: Deeper water.
Distribution: Brittanny, Plymouth, Florida.
Type specimen information: No type material in BMNH.
Remarks
The status of this species needs to be clarified. It is unlikely that the Florida specimen and the European specimens are conspecific. Both the Roscoff and the Plymouth records have not been substantiated by a description, and in faunal lists (Burton, 1957; Borojevic et al., 1968), the name chrysalis Schmidt (1864) was used.
Source: Burton, 1963.