Borojevia croatica sp. nov.

urn:lsid:zoobank.org:act: A9F84084-E033-43A9-AB71-83670090C7C1

Fig. 5; Table 5

Etymology

From the type locality.

Material examined

Holotype

ADRIATIC SEA: near the Island of Čiovo, 43°28'58.5" N, 16°21'25.6" E, 5 m, collected by B. Pleše and V. Nikolić, 5 Nov. 2010 (PMR-13740 = UFRJPOR 6864, in ethanol).

Paratype

ADRIATIC SEA: same data as holotype (PMR-13741 = UFRJPOR 6865, in ethanol).

Colour

White in life and in ethanol.

Description

Cormus composed of regular and tightly anastomosed tubes (Fig. 5A). Water-collecting tubes are present and form a single apical osculum. The skeleton is composed of tripods, triactines and rare tetractines. It has no special organisation (Fig. 5B).

Spicules (Table 5)

TRIPODS. Regular (equiangular and equiradiate) or sagittal. Some of them have an elevated centre, but most appear like large regular triactines. Actines are conical, straight, with sharp tips (Fig. 5C). Size: 102.6/ 11.9 µm.

TRIACTINES. Regular (equiangular and equiradiate).Actines are conical, straight, with sharp tips (Fig. 5D). Size: 66.6/ 7.5 µm.

with spines. TETRACTINES. Regular (equiangular and equiradiate). Actines are conical, straight, with sharp tips (Fig. 5E). The apical actine has very short and abundant spines organised in parallel rows. These spines cover the first 2/3 of the apical actine (Fig. 5F). Size: 70.0/ 8.3 µm (basal actine); 20.0/5.0 µm (apical actine).

Ecology

Specimens were collected on a shaded, vertical, hard limestone bottom.

Remarks

The genus Borojevia is currently composed of five species: B. aspina (Klautau, Solé-Cava & Borojević, 1994), B. brasiliensis, B. cerebrum, B. paracerebrum (Austin, 1996) and B. tetrapodifera (Klautau & Valentine, 2003) . All of them show a very well defined cormus, with regular and tightly anastomosed tubes and water-collecting tubes. The skeleton is always composed of tripods, triactines and tetractines with spines on the apical actines. Tetrapods may also be present ( B. tetrapodifera). The sixth species of the genus, B. croatica sp. nov., is closer to B. cf. aspina in our ITS tree (Fig. 16). Both species have short spines; however, B. croatica sp. nov. has numerous spines, while in B. cf. aspina there are few.

Given that B. cerebrum is also present in the Adriatic Sea, the best way to differentiate it from B. croatica sp. nov. is by the shape and location of spines. They are shorter, more abundant and distributed along most of the actine length in B. croatica sp. nov., and larger, fewer and scattered only near the tip of the apical actine in B. cerebrum .