Sponge Guide

UNCW National Science Foundation Valdosta State University Universidad Nacional de Colombia

Observed Characteristics:


  • black
  • purple-violet


  • encrusting


  • soft
  • tough

Sample Locations:

  • Bahamas
  • United States

Iotrochota arenosa

Notes: Thickly encrusting, irregular outline, deep purple to black, but somewhat transparent, usually partly buried on sediments; it produces abundant mucus which stains the fingers. Material from the Bahamas does not have birotule microsclere spicules, and megaslclere spicules are thin, curved to straight strongyles, often with a slight swelling at one or both ends. The lack of style spicules and birotules in Bahamian material, parallel what is found in local populations of Iotrochota birolulata (Higgin, 1877), also included here, which Rützler et al. (2007) named I. atra (Whitfield, 1901). A specimen from the Florida Keys had the usual megasclere spicule complement of the species (curved styles and strongyles, some oxeote; straight strongyles), and also lacked birotula microsclere spicules. This species is thicker than Artemisina melana van Soest, 1984, also pictured here, with it which may be confused in the field. Encrusting reef deep wall specimens with a brightly colored green skin, pictured in this catalogue, were assigned tentatively to I. birotulata, pending detailed examination of the spicules.

Author Reference: Rützler, Maldonado, Piantoni & Riesgo, 2007


Link: World Porifera Database