Guancha blanca

Miklucho-Maclay, 1868

Species Overview

Guancha blanca Miklucho-Maclay, 1868 is an easily recognizable calcareous sponge because of its globular body on a thin stalk, making it resemble a balloon on a string. It is whitish in colour. It is often overlooked because of its small size. There is a second stalked similar sponge, G . lacunosa which differs in having oxeas next to to the triradiate spicules (microscopical examination).

Taxonomic Description

Colour: Whitish.
Shape, size, surface and consistency: Stipitate, small, consisting of a tightly interlocked mass of tubules. Seldom exceeding 3 mm in height. Apical oscule. Consistency fragile.
Spicules: (Guancha blanca spics) Calcareous. Triactines only, equiangular or sagittal, basal rays: 75-90 µm long, paired rays: 30-45 µm.
Skeleton: Ascon-type arrangement.
Ecology: From the Laminaria-zone to 830 m.
Distribution: Arctic, Norway, Baltic, Atlantic; also reported from the Mediterranean and the Indian and Pacific Ocean.
Type specimen information: No type material in BMNH.

Remarks

This species differs from the closely similar G . lacunosa in the absence of oxeas. Originally it was recorded from the Arctic, but subsequently from other parts of the world. These subsequent records need confirmation.
Source: Burton, 1963.