New Genus and species of Heteroxyidae from Brazil (Axinellida: Demospongiae: Porifera), with a revised identification key for the family Author Santos, George Garcia Author Pinheiro, Ulisses Author Hajdu, Eduardo Author Soest, Rob Van text Zootaxa 2016 4158 1 105 116 journal article 10.11646/zootaxa.4158.1.6 c7cca607-f29d-4b54-9bd3-479da952a9a6 1175-5326 261459 5AC8AC88-0AD2-4D70-AE0B-7FE4770DE159 Genus Alveospongia gen. nov. Diagnosis. Heteroxyidae with saccular or alveolar shape, with rugose-microhispid surface. Ectosomal skeleton a thick crust of tangentially placed styles/strongyles. Choanosomal skeleton a confused arrangement of single styles/ strongyles, or widely spaced reticulate bundles of these megascleres with little spongin. Megascleres are a single category of styles/strongyles. Microscleres sinuous acanthomicrostrongyles stewn at random. Type species. Alveospongia sinuosclera sp. nov. (designation herein). Etymology. The generic name, Alveospongia is used as a noun, derived from the Latin alveos (cavity, trough, pit, hollow, channel), in reference to the saccular morphology of the holotype of the species described below. Remarks. Table 1 summarizes the main morphological characters of all genera currently assigned to Heteroxyidae according to van Soest et al. (2016) , and contrasts these to the characters observed in Alveospongia gen. nov. No other genus in the family has a saccular-alveolar growth form and sinuous acanthomicrostrongyles, but the (para)tangential ectosomal architecture is shared with Julavis and Parahigginsia ; the vague choanosomal reticulation is also present in Desmoxya , Julavis , Microxistyla and Negombo ; and styles occur in every genus, except Didiscus , Heteroxya and Parahigginsia . This combination of characters makes us confident that assignment of Alveospongia gen. nov. to Heteroxyidae is the best allocation in the current classification, at the same time recognizing that a new genus is also warranted. A revised identification key for genera of Heteroxyidae is provided below, including the new genus proposed here, as well as Alloscleria and Desmoxya , absent from the key proposed by Hooper (2002), when both were considered junior synonyms of Halicnemia Bowerbank, 1864 and Higginsia Higgin, 1877 , respectively.