Tsitsikamma (Clavicaulis subgen. nov.) pedunculata Samaai & Kelly, 2003

Samaai, Toufiek, Kelly, Michelle, Ngwakum, Benedicta, Payne, Robyn, Teske, Peter R., Janson, Liesl, Kerwath, Sven, Parker, Denham & Gibbons, Mark J., 2020, New Latrunculiidae (Demospongiae, Poecilosclerida) from the Agulhas ecoregion of temperate southern Africa, Zootaxa 4896 (3), pp. 409-442 : 426-427

Tsitsikamma (Clavicaulis subgen. nov.) pedunculata Samaai & Kelly, 2003

( Fig. 11 , Table 1, 4)

Tsitsikamma pedunculata, Samaai, Gibbons, Kelly and Davies-Coleman, 2003: 19–20 , fig. 3G, 4F, 6B.

Tsitsikamma pedunculata, Parker-Nance et al. 2019: 109–112 , figure 2a–l; table 2.

Material examined. Holotype — NHMUK 2003.1 .10.2, Thunderbolt Reef, Cape Recife, St. Francis Bay , 34.053° S, 25.689° E, 40 m, collected by Patrick L. Colin, CRRF, 25 Feb 1999.

Type locality. St. Francis Bay , Algoa Bay, Agulhas ecoregion, South Africa .

Distribution. Algoa Bay, Agulhas ecoregion, South Africa.

Diagnosis. Sponge pedunculate, body 5 cm diameter, up to 8 cm high, stalk 3–4 cm long, surface smooth and crowded with small, button-shaped oscules, 0.5–2 mm wide, 3 mm high and with numerous circular fungiform areolate porefields, 4–5 mm wide, 6 mm high, without membrane ( Fig. 11A ). A very tough leathery purse surrounds a much softer choanosome that pulls away from the outer case upon collection. Sponge is extremely resilient, leathery and compressible; colour in life is salmon pink to pinkish brown; between the oscules and areolate porefields the colour is dark pink ( Fig. 11A ); some specimens might appear as turquoise to dark purple in situ under low light conditions (see Fig. 2 in Parker-Nance et al. 2019); In alcohol, the ectosome is either brown, olive green, cream to tan colour and the choanosome is dark brown or tan. In preservative the ectosome is brown, the choanosome is dark brown ( Fig. 11A ). The choanosome consists of a thick ‘purse’ of tangential megascleres (the ectosome) surrounding a much softer choanosome containing an irregular reticulation of wispy tracts of smaller styles; the choanosome detaches and falls away from the ectosomal purse when bought from the water ( Fig. 11D ). The ectosome is composed of a thick, dense feltwork of tangential and paratangential anisostyles. A single layer of erect isochiadiscorhabds lines the surface of the ectosome. Megascleres ( Tables 1, 4) are styles, in two sizes: (1) slightly curved, thickened centrally 684 (591–728) × 16 μm; (2) thinner slightly curved centrally 536 (500–555) × 11 μm. Microscleres ( Tables 1, 4) are isochiadiscorhabd ( Fig. 11B, C ) with two whorls of cylindrical-conical tubercles, median whorl absent, the apex of each tubercular projection is acanthose: 29 (27–30) × 7 μm. Sponge is found in an exposed coastal bay (Algoa Bay) rooted in sandy substrata, abundant between 34– 40 m. The sponge contains biologically active pyrroloiminoquinone alkaloids, discorhabdin V and discorhabdin derivatives +14-Bromo-3-dihydrodiscorhabdin C that may have pharmacological potential [Cytotoxicity against Human Colon Tumour cell line (HCT 116)] ( Antunes et al. 2004, 2005).

Remarks. Tsitsikamma (C. subgen. nov.) pedunculata was described from a single specimen, the holotype, and was considered rare. Currently, the species is found to be abundant on deep reef systems between 34–40 m (Parker-Nance et al. 2019). Note that the in-situ photographs of turquoise to dark purple specimens, observed by Parker-Nance et al. (2019), are due to low light conditions during the survey period.

Tsitsikamma (T.) favus , T. (T.) amatholensis sp. nov., T. (C. subgen. nov.) pedunculata and T. (C. subgen. nov.) michaeli are sympatric in Algoa Bay, but distinguishable in the field based on colouration and external morphology (see Table 1; Figs 8 , 10E , 11A ): T. (C. subgen. nov.) pedunculata is either salmon pink and stalked; T. (T.) favus is semispherical and dark brown; T. (C. subgen. nov.) michaeli is small olive green purse-like with short stalk-like structure (due to thickening of the ectosome) or sessile (see fig. 4 in Parker-Nance et al. 2019). Tsitsikamma (C. subgen. nov.) pedunculata also have a purse-like ectosome, being very leathery, forming a single chamber as opposed to the numerous honeycomb chambers typical of T. (T.) favus . The key taxonomic differences are the morphology and size of the isochiadiscorhabd; in T. (C. subgen. nov.) pedunculata it is much smaller, has only two cylindrical conical tubercules which is arranged in groups of three and the primary megascleres are slightly smaller and thinner in comparison to T. (C. subgen. nov.) michaeli and T. (T.) favus (see Tables 1, 2 and 4).

Figures

FIGURE 2. Distribution of the two major ocean currents that sweep the coastal regions of South Africa; the warm Agulhas current on the south and east coasts, and the cold Benguela current on the west coast. Green circles indicate areas of coastal upwelling.

FIGURE 8. Variation in in situ morphology and colouration of Tsitsikamma favus Samaai & Kelly, 2002. Specimens collected from (A) Tsitsikamma National Park, (B) St. Francis Bay, (C) Tsitsikamma National Park, (D) Grootbank, Plettenberg Bay, (E) Algoa Bay, (F) St. Francis Bay, (G) Algoa Bay, (H) Jeffreys Bay, (I) Jeffreys Bay.

FIGURE 10. Tsitsikamma (T.) scurra Samaai & Kelly, 2003, holotype NHMUK2003.1.10.3: A. Preserved holotype; B, C. Isospinodiscorhabds from holotype; D. Skeletal architecture from holotype showing the ectosome (dark band) and choanosome of Tsitsikamma (T.) scurra. Tsitsikamma (T.) amatholensis sp. nov.: E. Preserved paratype SAMC-A090877; F–H. Isochiadiscorhabds from paratype; I. Preserved holotype SAMC-A090878; J–L. Isochiadiscorhabds from holotype; M. Skeletal architecture of holotype showing ill-formed, irregular reticulation of anisostyles and a single layer of erect isochiadiscorhabds lines the surface of the ectosome.

FIGURE 11. Tsitsikamma (C.) pedunculata Samaai & Kelly, 2003, holotype NHMUK2003.1.10.2: A. In-situ image of holotype; B, C. Isospinodiscorhabds from holotype; D. Skeletal architecture of holotype showing thick ectosome and ill-formed choanosomal spicule tracts. Tsitsikamma (C.) michaeli Parker-Nance, 2019, specimen SAMC-A090893: E. Preserved specimen; F. Isochiadiscorhabds; G. Skeletal architecture showing ill-formed, irregular reticulation of anisostyles, a thick ectosome and a single layer of erect isochiadiscorhabds lines the surface of the ectosome.