Chalinula Schmidt, 1868

Bispo, André, Willenz, Philippe & Hajdu, Eduardo, 2022, Diving into the unknown: fourteen new species of haplosclerid sponges (Demospongiae: Haplosclerida) revealed along the Peruvian coast (Southeastern Pacific), Zootaxa 5087 (2), pp. 201-252 : 205

Genus Chalinula Schmidt, 1868

Definition. Choanosomal skeleton with secondary lines one or more spicules long. The skeleton might also be more isotropic, however it always has a few discernible primary and secondary lines. No ectosomal skeleton. Spongin scarce to abundant (modified from de Weerdt 2002).

Remarks. The definition of Chalinula is based on the number of spicules in the secondary lines of the choanosomal skeleton. Nevertheless, the skeletal architecture in the species of this genus is remarkably variable, as well as the amount of spongin ( de Weerdt 2000).

For instance, the type species C. renieroides Schmidt, 1868 might bear secondary lines 1–4 spicules long, though in type material they have predominantly 1–2 spicules ( de Weerdt 2000). In turn, C. zeae de Weerdt, 2000 also has secondary lines 1–2 spicules long. On the other hand, variability in the skeleton of C. molitba (de Laubenfels, 1949) is extreme, a species that can develop (1) isotropic reticulation of spongin fibres cored by oxeas, (2) anisotropic reticulation with secondary lines 1–3 spicules long and intermediate amounts of spongin, (3) isotropic and unispicular reticulation of oxeas with scarce spongin ( de Weerdt 2000). The presence of several intermediate forms between these distinct skeletal arrangements of C. molitba preclude their designation as different species ( de Weerdt 2000). Thus, in order to cover the variability in skeletal features, including the number of spicules in secondary lines and amount of spongin, we made a small amendment on the definition of Chalinula .