Tsitsikamma pedunculata Samaai, Gibbons, Kelly & Davies-Coleman, 2003

Parker-Nance, Shirley, Hilliar, Storm, Waterworth, Samantha, Walmsley, Tara & Dorrington, Rosemary, 2019, New species in the sponge genus Tsitsikamma (Poecilosclerida, Latrunculiidae) from South Africa, ZooKeys 874, pp. 101-126 : 106-109

Tsitsikamma pedunculata Samaai, Gibbons, Kelly & Davies-Coleman, 2003 Figure 2 a–l

Tsitsikamma pedunculata Samaai, Gibbons, Kelly and Davies-Coleman, 2003: 19.

Type locality.

Holotype. - NHMUK 2003.1.10.2 (CASIZ 300661): Thunderbolt Reef off Cape Recife, St. Francis Bay, Eastern Cape Province, -34.05233, 25.68933, 40 m depth, 25 February 1999, collected by P.L. Colin, CRRF (after Samaai et al. 2003).

Material examined.

SAIAB 207194: St. Francis Bay, 5 November 2002, specific collection site unknown; SAIAB 207195, SAIAB 207196: Evans Peak, Algoa Bay, Eastern Cape Province, -33.84418, 25.81522, 34-38 m depth, 30 October 2015, collected by Ryan Palmer and Shirley-Parker-Nance, ROV from the coastal Research Vessel uKwabelana; SAIAB 207197, SAIAB 207198, SAIAB 207199, SAIAB 207200: Evans Peak, Algoa Bay, Eastern Cape Province, -33.84548, 25.81663, 30-34 m depth, 12 November 2015, collected by Ryan Palmer and Shirley-Parker-Nance, ROV from the coastal Research Vessel uKwabelana

Diagnosis

(emended from Samaai et al. 2003). Characteristic dirty pink, pink-brown pedunculate species with well-defined, ball-shaped head, up to 7 cm in diameter, on a narrow stalk, 1-3 cm wide and up to 7 cm long ( Fig. 2a, b ). Living sponges appear dirty pink although this is often obscured by epibionts, especially the yellow encrusting Mycale (Mycale) sponge also found growing on other members of this genus ( Fig. 2 a–c ). Freshly collected material is a dusty pink to pink-brown to dark purple while preserved material has an olive green, cream to tan colour ( Fig. 2c ). Small well-spaced cone-shaped oscula 1.5-2 mm high and 1.5-3 mm in diameter are present over the upper part of the head gradually replaced by small to bigger elevated circular fungiform areolate porefields, 1-4.5 mm high and 2-7.5 mm in diameter, toward the base where the stalk is attached ( Fig. 2a ). In preserved specimens the oscula retain their shape but the upper border of the porefields contracts inwards giving it a button like appearance. A tough, resistant leathery ectosome surrounds a much softer choanosome. The sponge is resilient, but compressible. Salmon pink to pinkish brown between the oscula and dark pink between the areolate porefields.

Skeleton.. Microscleres are abundant throughout the choanosome and form an irregular palisade of oblique or erect microscleres over the dense feltwork of tangential and paratangential styles together forming the ectosome (Table 2 , Fig. 2e ) The resistant ectosome encapsulate soft choanosome with delicate tracts ( Samaai et al. 2003) ( Fig. 2d ). The stalk consists of densely arranged spicules and has longitudinal cavities filled with soft choanosome tissue distributed regularly along the axis of the reinforced stalk ( Fig. 2c, f ).

Spicules. Megascleres consist of two size classes of styles; (i) slightly sinuous, robust centrally thickened, acerate, conical, hastate or somewhat blunt even mucronate styles, and (ii) thin conspicuously sinuous and sometimes conspicuously centrally thickened styles (Table 2 , Fig. 2g, h ). Microscleres. Isochiadiscorhabds with only two whorls of cylindrical, conical tubercles acanthose on apex, arranged on the ends of a short shaft ( Samaai et al. 2003). The large manubrium is easily distinguishable from the conspicuously smaller apex with terminally acanthose tubercles arranged in a pincushion-like way to form the apex whorl of the microsclere (Table 2 , Fig. 2 i–l ).

Distribution.

Algoa Bay and St. Francis Bay

Substrate, depth range and ecology.

Abundant on deep reef systems between 34-40 m. All specimens collected were attached to rock on the sides of medium profile reef adjacent to sandy gullies. A thin delicate light yellow Mycale (Mycale) species is commonly found growing on the globular head surface around the oscula and porefields.

Remarks.

The shape of the sponge, the long peduncle, round head, colour and the shape of the microscleres set this species well apart from any other species in this genus.

No intraspecific genetic diversity was found for the 28S rRNA gene sequence of specimens of T. pedunculata included in this study. An interspecific genetic diversity of 0.32-0.65 % for the 28S rRNA gene sequence was found between T. pedunculata and T. favus (Suppl. material 1: Table S1).

Figures

Figure 2. Tsitsikamma pedunculata a, b in situ c collected specimens showing vascular stalk and covered with sponge epibiont Mycale (Mycale) sp. SAIAB 207196 d section of ectosome with underlying choanosome SAIAB 207166 e outer section of ectosome with chiadiscorhabds in a dense layer externally SAIAB 207166 f section through the stalk showing lumen of vascular-interior SAIAB 207166 g, h various sinuous styles i, j collection of SEM images of chiadiscorhabds k, l light microscope image of chiadiscorhabds. Scale bars 6 cm (b); 1 cm (d); 100 µm (g, h); 20 µm (i-l).