Antipathes cf. griggi Opresko, 2009

Bacharo, Kurt Bryant B. & Sotto, Filipina B., 2020, A new distributional record of the black coral Antipathes cf. griggi in Mactan Island, Philippines, Zootaxa 4759 (1), pp. 143-146 : 143-145

Antipathes cf. griggi Opresko, 2009

Material Examined: USCBM 2674 , Agus , Mactan Island, 10° 16′ 26.06″ N, 123° 59′ 37.34″ E , SCUBA, 13 m depth, A. Ayop, N. Uy, P. Abella, February 2017 .

Description: The bushy colony ( Fig. 1 ) examined in-situ has a measured length of 21 cm. It has a colony growth of vertically directed branchlets that can be branched or unbranched themselves. The endpoint of each sub-branches diverges into two, resembling a fork having two tines ( Fig. 2a ). The brownish to brick-reddish polyps at the terminal branchlets of the colony are arranged in a single series ( Fig. 2b ) with a transverse diameter of 1.01 mm (0.88–1.3 mm) and are spaced 1.12 mm (0.96–1.35 mm) apart, with 8–10 polyps per centimeter. Length of the sagittal and lateral tentacles measured 0.36 mm (0.27–0.46 mm) and 0.34 mm (0.28–0.44 mm) respectively. The skeletal branch diameter ( Fig. 3 ) without spines measured 0.73 mm (0.72–0.74 mm). Polypar spines measured 0.19 mm (0.18–0.20 mm) in height while the abpolypar spines measured 0.11 mm (0.10–11 mm) and are spaced 0.52 mm (0.50–0.53 mm). The examined primary spines ( Fig.

4a-c) vary in morphology, being laterally compressed and blunt, or multilobed, or with papillae. Additionally, the skeletal surface bears secondary spines ( Fig. 4 d-e) which measured 0.02 mm (0.01–0.03 mm).

ticosa and the Hawaiian species A. griggi . These species have similar branching pattern, spine morphology and size, and secondary spines, but differ in the density of the primary spines, density and size of secondary spines, and surface features of the skeletal spines from the different portions of the branch depending on the diameter ( Opresko 2009). The examined specimen closely resembles A. griggi in terms of size and height of the secondary spines, which are less than 0.04 mm, compared to those of A. fruticosa which reaches 0.05 mm. The density of the secondary spines in the examined specimen are more similar to those of A. griggi than those of A. fruticosa , as A. griggi has 2–3 spines per 0.01 mm 2. Though there are similarities with the original description of the holotype of A. griggi there are also differences: the examined specimen’s branching pattern is less dense and not as uniserial and its spines are much blunter. The slight morphological differences reveal that there is much uncertainty in the taxa that warrants the use of molecular tools for verification and confirmation.

Distribution: A. griggi has only been documented from the Hawaiian archipelago at 10–110 m ( Opresko 2009; Wagner 2015). Wagner (2015) suggested that colonies found in the Indo-Pacific that are identified with the Mediterranean species A. dichotoma were misidentified, since the Indo-Pacific is outside the distribution range of A. dichotoma . The result of this taxonomic investigation is the first record of the species outside the Hawaiian Archipelago and further provides support to the claim of Wagner (2015).

Figures

FIGURE 1. Antipathes cf. griggi colony in-situ in the locality area of Barangay Agus, Mactan Island, Philippines. Photo courtesy of Antonio Ayop.

FIGURE 2. Polyps of Antipathes cf. griggi on the terminal branch when viewed under stereoscope. Scale bars: 1 mm (a, b). Remarks: The gross morphology of the examined A. cf. griggi specimen is similar to the New Zealand species A. fru-

FIGURE 3. Skeletal branch diameter of Antipathes cf. griggi on the terminal branch when viewed under SEM. Scale bar: 0.2 mm.

FIGURE 4. Close-up view of the primary spines (a-c) and secondary spines (d-e) of Antipathes cf. griggi when viewed under SEM. Scale bars: 0.01 mm (a, e), 0.02 mm (b, c, d).