Cyclacanthia mzimayiensis, Samaai, Toufiek, Govender, Vasha & Kelly, Michelle, 2004

Samaai, Toufiek, Govender, Vasha & Kelly, Michelle, 2004, Cyclacanthia n. g. (Demospongiae: Poecilosclerida: Latrunculiidae incertea sedis), a new genus of marine sponges from South African waters, and description of two new species, Zootaxa 725, pp. 1-18 : 12-13

publication ID	https://doi.org/ 10.5281/zenodo.169508
DOI	https://doi.org/10.5281/zenodo.5662343
persistent identifier	https://treatment.plazi.org/id/BA3D8786-5927-FFA5-FEB5-F9A1FDB0F8BC
treatment provided by	Plazi
scientific name	Cyclacanthia mzimayiensis
status	sp. nov.

Treatment

Cyclacanthia mzimayiensis View in CoL sp. nov.

( Figs. 2 View FIGURE 2 G, H, 3C, D, 4C, F, 4D, G, 5C, D, E, F)

Holotype material. SAM H 5082: Mzimayi reef, Sizela, south of Durban, east coast of South Africa, 30° 37 137 'S, 31° 16 112 'E, 29 m, collected by T. Samaai and C. Lawrence, EKZN, 16 October 2003.

Paratype material. SAM H 5081: Umkomaas, Aliwal Shoal, east coast of South Africa, 30° 26 202 'S, 32° 0 2 558 'E, 18 m, collected by T. Samaai, 4 September 2003. Description. Thinly encrusting sponge, 2–3 mm thick, forming a patch c. 28 mm x 35 mm diameter, incorporating sand, pebbles, barnacles, and other foreign material ( Fig. 3 View FIGURE 3. A C, D). Surface smooth, with low volcano shape oscules, 3 mm high x 2 mm wide at base, 1 mm at apex, and a few nodular truncate areolate porefields, 2 mm high x 2 mm wide. Texture is incompressible and crumbly due to incorporation of substrate. Ectosome readily separable from the underlying choanosome. Colour in life lime green, in preservative dark green.

Spicules. Megascleres— Styles: Smooth, straight, occasionally wavy, occasionally centrally thickened, narrow proximal region, fusiform: 268 (182–363) x 5 µm ( Fig. 4 View FIGURE 4. A D, G). Paratype ( SAM H 5081) style length; 276 (315–200) x 5 µm ( Fig 4 View FIGURE 4. A C, F). Microscleres— isospinodiscorhabds: The apical whorl has 3 groups of 3 spines radiating obliquely from the shaft away from the median whorl, each with several additional spines. The apex is armoured with a single irregular spike that may be irregularly spined. The manubrium is identical to the apical whorl, the apex is also armoured with a single irregular spike that may be irregularly spined. The median whorl is equidistant from both apical whorl and manubrium; 4 groups of 2 spines are directed horizontally from the shaft: 39 (30–48) µm (Holotype) ( Fig. 2 View FIGURE 2 G), 35 (30–44) µm (Paratype) ( Fig. 2 View FIGURE 2 H).

Skeleton. Thick tracts 196–245 µm emanate from the deep choanosome and diverge towards the surface forming plumose tracts 274–392 µm wide The upper choanosome has an irregular polygonalmeshed reticulation formed by wispy tracts of smooth styles ( Fig. 5 View FIGURE 5 E, C). Interstitial megascleres and microscleres are abundant, as are sand particles and other foreign materials. The ectosome is a thin paratangential layer of megascleres, c. 98 µm thick, and is aligned with an irregular palisade of isospinodiscorhabds ( Fig. 5 View FIGURE 5 F, D).

Ecology. The holotype was collected at Mzimayi reef, on a flat rocky ledge at the edge of the vertical section of the reef, at 29 m depth. This species is cryptic, accounting for its apparent rarity, and appears to grow where there is strong current flow. The paratype was found at Aliwal Shoal, on the southern edge of the reef complex, in a small crevice on a boulder, at 17 m depth. The sponge was barely visible, being covered with sand, and only the areolate porefields were visible.

Etymology. Named after the type locality, Mzimayi Reef, south of Durban

Remarks. C. mzimayiensis sp. nov. is clearly differentiated from C. bellae (Samaai & Kelly) and C. cloverlyae sp. nov. in habit; the sponge is very thinly encrusting over sandy pebbles, and it incorporates much foreign material. C. mzimayiensis sp. nov. is also lime green, as unusual colour for any latrunculiid sponge, and it is hard, and incompressible, while C. cloverlyae sp. nov. is relatively fleshy. The morphology of the microscleres further differentiates these species; the microscleres of C. mzimayiensis sp. nov. are more irregularly ornamented, compared to those of C. cloverlyae sp. nov., in particular, and they are medium in overall dimensions compared to those of both species ( Table 1 View TABLE 1 ). C. cloverlyae sp. nov and C. mzimayiensis sp. nov. are separated by habitat, the former is found in a turbid, sandy reef environment and the latter in deeper waters on a rocky platforms associated with hard coral and algae.