Ircinia Nardo, 1833

Kelly, Joseph B. & Thacker, Robert W., 2021, New shallow water species of Caribbean Ircinia Nardo, 1833 (Porifera: Irciniidae), Zootaxa 5072 (4), pp. 301-323 : 304

Genus Ircinia Nardo, 1833

Diagnosis. The proteinaceous skeleton of irciniids is composed of primary fibers that are meshed together in fascicles. A system of secondary fibers intersect, often perpendicularly, with the fascicles and can differ in the degree of coring and fiber widths relative to the primary fibers. The networks of interconnecting secondary and fascicular primary fibers are reinforced by nearly transparent, thin fibers (termed irciniid filaments) that can be tightly packed in pleatlike layers or arranged in tracts, making the bodies of many irciniids compressible though difficult to tear. Ircinia are distinguishable from Psammocinia Lendenfeld, 1889 by the former’s absence of a thick outer layer of sediment that forms a cortical armor. The dermis of Ircinia is conulated and often clear of epibiont growth. Ircinia display a wide range of intraspecific variation in morphological characters at the macro- and microscopic level. Modified from Hooper & van Soest (2002); see Discussion for remarks on secondary fiber coring.