Heterogorgia uatumani Castro, 1990

Breedy, Odalisca & Guzman, Hector M., 2011, A revision of the genus Heterogorgia Verrill, 1868 (Anthozoa: Octocorallia: Plexauridae), Zootaxa 2995, pp. 27-44 : 37-39

Heterogorgia uatumani Castro, 1990

( Figs. 8 , 9 )

Heterogorgia uatumani Castro, 1990: 415 –418; Castro et al. 2010: 776 –779; Breedy & Guzman 2005: 805.

Material examined. Holotype. MNRJ 0 1233, ethanol preserved, off Ponta Grossa do Sítio Forte, Grande Island, Angra dos Reis, RJ, Brazil (26°06.8ʹ S, 44°17.6ʹ W), 8–15 m, C.B. Castro and C.A. Secchin, 21 November 1982. Paratypes. USNM 73432, ethanol preserved, Grande Island, Brazil, 8–15 m, C.B. Castro, 21 November 1982; USNM 73431, two colonies, ethanol preserved, Amendoim Island, Brazil, 9–13 m, C.B. Castro, 6 November 1981; USNM 73569, three colonies, ethanol preserved, Laje dos Moleques Sao Senastiao Channel, Brazil, 6 m, P.S. Young, 4 May 1984.

Description of the holotype. The colony is irregularly branched, up to 11 cm tall. Several stems arise from a common encrusting holdfast and branch several times mostly in a single plane, the diameter of the stems including calyces, reaches up to 4.5–5 mm, and is about the same diameter at the tip. The polyps are bright yellow when alive ( Castro 1990) and distributed all around the branches, not very close together (about 12–20 calyces/cm) and more scarcely distributed on the holdfast and at the base of the branches ( Fig. 8 ). The calyces are prominent, up to 1.5 mm tall and 1.2 mm diameter, with a weak arrangement of thorns on the rim. The anthocodial armature is composed of a strong points of 5 to 6 pairs of spindles arranged en chevron, measuring 0.20–0.33 mm long and 0.02– 0.05 mm wide ( Fig. 9 G), but a collaret is absent. The point sclerites are bent or straight, some with a spiny distal end, and there are sparse spines on the surface. The calicular rim bears one whorl of projecting thorns, 0.25–0.32 mm long and 0.05–0.06 mm wide and the shaft of the thorns tends to be serrated or spiny ( Fig. 9 G). The coenenchymal sclerites comprise: small tuberculate radiates, 0.075–0.085 mm long and 0.05–0.06 mm wide ( Fig. 9 E); warty ovals, 0.09–0.13 mm long and 0.06–0.10 mm wide ( Fig. 9 D); crosses, 0.12–0.20 mm diameter ( Fig. 9 C) and various types of spindles, straight, reaching 0.22–0.32 mm long and 0.07–0.1 mm wide, with acute ends ( Fig. 9 A), and irregularly branched or lobed, 0.18–0.30 mm long and 0.06–0.13 mm wide ( Fig. 9 B). The tentacles bear tuberculate rods, 0.11–0.13 mm long and 0.014–0.03 mm wide ( Fig. 9 H). A complete description of the holotype is given by Castro (1990: 415–420).

The colour is whitish to beige or brownish either in ethanol or dry preserved.

Remarks. There is a lot of variation in sclerite shape among specimens of H. uatumani and even among calyces of the same specimen, especially the "palisade" sclerites (thorns around the calicular rim) (Castro, pers. com.). The absence of a collaret in this species is not consistent with this genus, and, along with other differences given in Table 2 , definitely separates this species from the others. However, another more precise taxonomic allocation for this species in another genus cannot be presently resolved.

Heterogorgia uatumani is the only record for this genus in the Atlantic Ocean so far. It has been reported at various localities off the coast of Brazil, from Amapá State to Santa Catarina State ( Castro et al. 2010), and also from the north-west Caribbean ( Humann 1994), with a depth range of 6– 15 m.

maximum size found for each species. Sclerite ranges represent the average minimum and the maximum size measured in all

the samples. All measures are given in mm.

Species H. hickmani H. papillosa H. tortuosa H. verrucosa H. uatumani Points spindles 0.4–0.5 x 0.04– 0.20–0.35 x 0.02– 0.16–0.34 x 0.02– 0.025–0.51 x 0.04– 0.20–0.41 x 0.02–

0.06 0.04 0.05 0.05 0.05

Figures

FIGURE 8. Heterogorgia uatumani, holotype, MNRJ 01233: (A) colony; (B) detail of a branch.

FIGURE 9. Heterogorgia uatumani, holotype, MNRJ 0 1233, sclerites: (A) spindles; (B) irregularly branched or lobed spindles; (C) crosses; (D) warty ovals; (E) radiates; (F) thorns; (G) point spindles; (H) tentacular rods.

Tables

TABLE 2. Comparative characteristics of the Heterogorgia species. Diameter of branches and calyces represent the average

Max. No. branching	2	4	7	4	4
Stem diameter	12–19	4–4.5	4–6	7–12	4–4.5
Calyces/cm	40–50	25	14	20–24	12–20
Calyx diameter	2.1	0.5	1.6	1.8	1.2
Calyx height	1	1	1	1.2	1.5
Collaret spindles	0.5–0.7 x 0.05– 0.13	0.26–0.43 x 0.03– 0.05	0.27–0.55 x 0.03– 0.08	0.35–0.56 x 0.05– 0.10	absent