Borojevia trispinata Azevedo, Padua, Moraes, Rossi, Muricy & Klautau, 2017

Borojevia trispinata Azevedo, Padua, Moraes, Rossi, Muricy & Klautau, 2017 View in CoL

( Fig 8 View FIGURE 8 ; Table 5 View TABLE 5 )

Synonyms: Clathrina aspina, Azevedo & Klautau 2007: 4 , Klautau et al. 2013: 448. Clathrina aff. aspina, Rossi et al. 2011: 1028 . Borojevia aspina, Imesek et al. 2014: 22 , Lanna & Klautau 2015: 3, Azevedo et al. 2015: 792. Borojevia cf. aspina, Klautau et al. 2016: 5 . Borojevia trispinata, Azevedo et al. 2017: 313 , Fonseca et al. 2023: 67.

Material examined: UFRJPOR 8802 , UFRJPOR 8804 , UFRJPOR 8820 , UFRJPOR 8821 , UFRJPOR 8826 , UFRJPOR 8922 , Escalvada Island , 7.6–15 m depth, 29.iii.2017 – 04.iv.2017, colls. A. Padua and C. Leal. UFRJPOR 8923 , Marine Artificial Reef Victory 8B , 22 m depth, 30.iii.2017, colls. A. Padua and C. Leal .

Diagnosis: “ Borojevia with triactines, tetractines and tripods. There are only three spines radially disposed in one row on the apical actine of the tetractines” ( Azevedo et al. 2017).

Description: Cormus formed by thin, regular and tightly anastomosed tubes. Water-collecting tubes present. Colour white alive and in ethanol ( Figs 8A, B View FIGURE 8 ). Consistency soft and compressible. Tubes smooth. Aquiferous system asconoid.

Skeleton composed of tripods, triactines and tetractines ( Fig 8C View FIGURE 8 ). Tetractines are the most abundant spicules and their apical actine can have a single row with three spines or present no spines ( Fig 8D View FIGURE 8 ). Trichoxeas are present.

Spicules ( Figs 8D–G View FIGURE 8 ; Table 5 View TABLE 5 ).

Tripods: Regular to subregular or parasagittal. Actines conical, straight, with sharp tips ( Fig 8E View FIGURE 8 ). Size: 91.1 (± 10.5)/ 12.8 (± 0.7) µm (N = 8).

Triactines: Regular. Actines conical to slightly conical, undulated, with sharp tips ( Fig 8F View FIGURE 8 ). At the oscular region, they become sagittal. Size: 87.3 (± 6.1)/ 11.1 (± 1.0) µm (N = 20).

Tetractines: Basal actines similar to the triactines. Apical actine long, conical, with a slightly curved sharp tip ( Fig 8G View FIGURE 8 ), ornamented with a single row with three spines or without spines ( Fig 8D View FIGURE 8 ). Size: basal actine—88.8 (± 6.7)/ 11.1 (± 1.2) µm (N = 20); apical actine—61.1 (± 8.9)/ 10.1 (± 0.6) µm (N = 20).

Ecology: Preference for shaded habitats, such as crevices, from 1 to 15 m of depth ( Azevedo et al. 2017).

Distribution: São Pedro and São Paulo Islands ecoregion—São Pedro and São Paulo Archipelago (type locality; Azevedo et al. 2017). Eastern Brazil ecoregion— Salvador, Bahia State ( Fonseca et al. 2023); Guarapari, Espírito Santo State (present study); Arraial do Cabo (Forno Beach), Rio de Janeiro State ( Klautau et al. 1994). Southeastern Brazil ecoregion—Angra dos Reis, Rio de Janeiro State ( Azevedo & Klautau 2007; Klautau et al. 2013, 2016).

Taxonomic remarks: Azevedo et al. (2017) described Borojevia trispinata based on specimens from the São Pedro and São Paulo Islands ecoregion. In that work, the authors mentioned that some DNA sequences and specimens previously identified as Borojevia aspina ( Klautau, Solé-Cava & Borojević, 1994) , B. cf. aspina and B. aff. aspina from Angra dos Reis (Southeastern Brazil ecoregion) and Arraial do Cabo (Forno Beach) (Eastern Brazil), both in Rio de Janeiro State, were, in fact, B. trispinata ( Azevedo & Klautau 2007; Klautau et al. 2013), a sympatric species.

Reanalysing the holotypes of B. trispinata and B. aspina , we observed that both species have some tetractines with smooth apical actines and some actines with spines. Nonetheless, in B. trispinata most of the apical actines have three well-developed spines organised in one row, while in B. aspina most of the apical actines have only vestigial spines. Unfortunately, we do not have sequences of B. aspina from the type locality available up to date.