Cycloperiella Canu & Bassler, 1923

Larré, Igor R. N. M., Almeida, Ana C. S. & Vieira, Leandro M., 2024, On some colorful bryozoans from Brazil: reevaluation of Aptonella violacea Canu & Bassler, 1928 and a new species of Cosciniopsis Canu & Bassler, 1927, Zootaxa 5506 (2), pp. 245-260 : 248

Genus Cycloperiella Canu & Bassler, 1923

Type species. Cycloperiella rubra Canu & Bassler, 1923

Aptonella Canu & Bassler, 1928 (n. syn.). Type species: Aptonella violacea Canu & Bassler, 1928 .

Diagnosis. Encrusting colonies with reddish-pigmented cystids. Zooids exhibit quincuncial growth. Frontal shield granular or nodular, with small pseudopores except around the orifice; marginal pores distinctly larger, sometimes elongate. Primary orifice with a semicircular distal margin, a broad proximal margin, and a pair of proximolateral condyles. Adventitious avicularia may be present, small, and typically positioned near the orifice with different orientations. Spines absent. Ovicelled zooids with raised peristome with a proximal pseudosinus. Ovicell hyperstomial, acleithral, with a cormidial ooecium, ectooecium with the same morphology as the frontal wall.

Remarks. Cycloperiella was first mentioned as a nomen nudum by Canu & Bassler (1920), with a formal description followed in Canu & Bassler (1923) ( Di Martino et al. 2019). However, this description lacked diagnostic characteristics for an accurate classification. The type specimen of Cy. rubra was illustrated by Di Martino et al. (2019, p. 42, fig. 35), who also reported the species from the Pliocene (Piacenzian) Tamiami Formation in Florida. The type material features zooids with a pseudoporous frontal wall (except around the orifice), cormidial ovicells having the same morphology as the frontal wall, orifices sometimes cormidial and with lunules, and peristomes forming a U-shaped pseudosinus in ovicelled zooids. These characteristics, along with the acleithral ovicells, led us to consider Aptonella Canu & Bassler, 1928 as a junior synonym of Cycloperiella Canu & Bassler, 1923 . Specimens of Cy. rubra reported by Di Martino et al. (2019) exhibit some differences from the type species, such as more and larger pseudopores on the frontal wall (30–40 compared to around 20 in the type specimen), and the presence of latero-oral avicularia (not observed in the type specimen), suggesting they may represent a distinct species.

The most recent reference that mentioned Cy. violacea n. comb. (as Aptonella violacea or Cosciniopsis violacea as a senior synonym) has placed it within Gigantoporidae , characterized by the presence of a membranous ectooecium ( Martha et al. 2020). However, an examination of Cycloperiella type materials revealed a calcified, pseudoporous, and cormidial ectooecium, making such classification unlikely. Additionally, Cycloperiella is morphologically distinct from other gigantoporids due to the absence of a tubular peristome and spiramen, features found in Gigantopora , Gephyrophora , and Barbadiopsis .

Currently, Cycloperiella is classified within Stomachetosellidae Canu & Bassler, 1917 ( Bock 2024; Di Martino et al. 2019), a taxon considered heterogeneous ( Dick et al. 2006; Zágoršek & Gordon 2013). Cycloperiella species, including Cy. violacea n. comb., exhibit characteristics that allow for classification within Stomachetosellidae , particularly based on the broad family diagnosis provided by Canu & Bassler (1917) and Martha et al. (2020). However, some diagnostic characters found in Cycloperiella species, such as the presence of latero-oral avicularia, condyles, and acleithral ovicells, appear to be lacking in Stomachetosella crassicollis Canu & Bassler, 1917 , the type species of Stomachetosella Canu & Bassler, 1917 ( Zágoršek & Gordon 2013). Furthermore, the presence of a calcified ectooecium and endooecium is a distinctive characteristic of the superfamily Smittinoidea Levinsen, 1909 [lepralielliform ovicell sensu Ostrovsky (2013)], in contrast to the partially or entirely membranous ectooecium found in Schizoporelloidea Jullien, 1883 [microporelliform ovicell sensu Ostrovsky (2013)], where Stomachetosellidae is currently classified.

The presence of lunula and cormidial ovicells found in Cycloperiella are characteristics observed in other families of Smittinoidea , such as Lanceoporidae Harmer, 1957 (1927) (e.g., Calyptotheca Harmer, 1957 and Stephanotheca Reverter-Gil, Souto & Fernández-Pulpeiro, 2012 ). However, species in this family have cleithral or subcleithral ovicells ( Martha et al. 2020) and lack the peristome in ovicelled zooids, which is characteristic of Cycloperiella . Another family with genera similar to Cycloperiella is Bitectiporidae MacGillivray, 1895 , diagnosed by the presence of a pseudoporous lepralioid frontal wall, an orifice with condyles but lacking lyrula and spines, and acleithral ovicells with a calcified ectooecium and endooecium ( Martha et al. 2020). Thus, here we propose transferring Cycloperiella to Bitectiporidae .