Bowerbank, 1864
Species Overview
Ciocalypta penicillus Bowerbank, 1864 is a very characteristic sponge with its massive base buried in the substrate (sand or gravel) and half a dozen or more conical, erect and firm fistules protruding above it. Colour white or cream, somewhat transparent.
Taxonomic Description
Colour: White-cream to cream-yellow to grey, both cushions and papillae.
Shape, size, surface and consistency: Very characteristic. The sponge consists of a basal cushion of up to 10 cm in diameter buried in sand or gravel, from which project large conical, translucent, ridged, thick walled, non-contractile fistules, normally up to about 5-9 cm high, 0.5-0.6 mm in diameter. The surface of the fistule has a glassy, translucent appearance, through which vertical spicule fibres can be seen with the unaided eye (Ciocalypta penicillus MCS2). These are responsible for the vertical ridges. Oscules are on top of some of the fistules (which are therefore exhalant processes). The oscules can be seen only when the sponge is undisturbed—underwater. Consistency: basal cushions are moderately firm, moderately elastic. Most of the fistules can be bent through 180 degrees without breaking, although some do break. Contraction not noticeable.
Spicules: (Ciocalypta penicillus spics) The spiculation is simple, consisting of large and small slender styles and occasional oxeas. These are incompletely differentiated into two size categories, averaging between 200 and 630 µm long. There are no microscleres. The spicules frequently have telescoped or distorted extremities, and it is possible that the oxeas are none other than modified styles. No microscleres.
Skeleton: (Ciocalypta penicillus skel) The main skeleton is an irregular, confused reticulation consisting mostly of larger spicules, with a tendency to form ascending fibres. In the fistules there is a central condensation with radially arranged ascending fibres. The ectosomal skeleton is a tangential reticulation (sometimes very diffuse), with smaller spicules predominant. There may be sub-surface spaces. Spongin is scarce.
Ecology: In clear water. Always with basal cushion buried in sand or gravel (never mud), which may be covered by a layer of silt. The usual habitat of clean coarse sand with some gravel indicates a preference for a degree of exposure to wave action.
Distribution: European seaboard of Atlantic from Helgoland south to Spain, Portugal Mediterranean, etc. Recorded in the British Isles from Coll/Tiree (W coast of Scotland) and Lundy (Ciocalypta penicillus BandW). Record from Holland is erroneous.
Etymology: Penicillus (Latin) = painter's brush or tuft, referring to the shape of the fistules in dried condition.
Type specimen information: Holotype BMNH 1877:5:21:1069 (Ciocalypta penicillus Type). Bowerbank's (1874) figured specimen: BMNH 1930:7:3:28 (Ciocalypta Bowerbank); MCS voucher: BELUM Mc548.
Remarks
May perhaps be confused with Polymastia spp. and other papillate genera. The larger size and thick ridged walls of the conical fistules some of which break if bent, and their glassy look, are very helpful features once learned. Also the fistules of Ciocalypta do not appear to contract or collapse as do those of Polymastia spp. In Polymastia mamillaris a network of spicule fibres can often be seen underwater in the papillae. The spicule fibres in the fistules of Ciocalypta are mainly vertical and do not form an obvious net. A related and somewhat similar species is Axinyssa digitata (Cabioch, 1968 as Pseudaxinyssa) , but this has an irregular habit and predominantly oxeas.
Source: Ackers et al., 1985 (Editors: S.M. Stone and D. Moss), 1992.