Cupressopathes cf. pumila ( Brook, 1889 )

Terrana, Lucas, Bo, Marzia, Opresko, Dennis M. & Eeckhaut, Igor, 2020, Shallow-water black corals (Cnidaria: Anthozoa: Hexacorallia: Antipatharia) from SW Madagascar, Zootaxa 4826 (1), pp. 1-62 : 52-54

Cupressopathes cf. pumila ( Brook, 1889)

Figs. 29 , 30

Antipathes pumila Brook 1889 , pl. XI, fig. 17

Cupressopathes pumila Opresko 2001, p. 356 –358.

Material examined. Entire colony, Toliara 24 m INV.131366 .

Depth range. 20–30 m.

Decription. The colony is branched and measures about 40 cm high and 25 cm wide with a basal diameter of 6.5 mm ( Fig. 29 , a). Each branch bears four irregular rows of primary pinnules that reach up to 5 cm in length ( Fig. 29 , b, c). Primary pinnules are inserted at an angle slightly less than 90° to the branch. The arrangement of primary pinnules does not give the typical overall bottle-brush appearance but rather a plumose aspect ( Fig. 29 , a). There are five to seven primary pinnules along one cm of the axis, counting those on all sides ( Fig. 29 , c). These primary pinnules can be pinnuated to 4 th order, some can be more densely pinnulated than the others ( Fig. 29 , d–f). The subpinnules are mostly biserial but they can also be uniserial ( Fig. 29 , e, f). Subpinnules are inserted at an acute angle to the primary pinnules with a general tendency to grow upwards, but this is not the case in many places ( Fig. 29 , c–f). Secondary pinnules are generally less than 2.5 cm in length, but at some places they reach lengths up to 5 cm ( Fig. 29 , e, f). Higher order pinnules are less than 1.5 cm long ( Fig. 29 , c–f). The polyps are slightly elongated transversally; they measure 0.4–1.0 mm in transverse diameter and are spaced 0.15–0.35 mm apart, with ten polyps along one cm. Polyps are located on a single side of the branches, but they can twist around it. On thicker branches, polyps are irregularly distributed.

The spines on pinnules and subpinnules follow the general gradual change seen within this genus, from conical and horn-shaped to acicular, sharp and needle-like ( Fig. 29 , g–n). They are finely papillose over two thirds of their height, with the papillae elongated towards the tip of the spines ( Fig. 29 , m, n). On the subpinnules these papillae tend to appear as faint striations and the spines almost appear smooth ( Fig. 29 , k, l). The spines are inclined upwards, which is more pronounced on abpolypar side, although on thicker branches this inclination is irregular ( Fig. 29 , g–j). On a subpinnule 0.13 mm in diameter, the spines are arranged in five longitudinal rows. The polypar spines measure 0.08–0.10 mm in height and are spaced 0.12–0.20 mm apart, while the abpolypar spines measure 0.07–0.09 mm and are spaced 0.11–0.18 mm apart. On a primary pinnule of 0.28 mm, six longitudinal rows of spines can be seen. The polypar and abpolypar spines measure 0.10–0.14 mm and 0.09–0.13 mm, respectively, and they are spaced 0.10–0.19 mm and 0.10–0.18 mm, respectively. On a thick branch of 1.3 mm in diameter, the longitudinal arrangement is lost, and the spines measure up to 0.26 mm. Bifid spines can also be found on such branches.

Taxonomic remarks. The present species differs from Cupressopathes abies in having a smaller, more flattened corallum with several of the primary pinnules developing into side branches ( Brook 1889, Opresko 2001, Fig. 30 a ). The typical bottle-brushed shape of Cu.abies is not found in this species ( Fig.30 ,a),as there is a tendency for its primary pinnules to have more irregular lengths along the corallum than those of Cu. abies . In general, compared to Cu. abies , Cu. pumila has more branches and a longer, less dense pinnulation, with a greater tendency for the subpinnules to be bilateral. Spines are similar to those of myriopathids ( Fig. 30 , b).

Distribution. India (type locality, Brook 1889), western Pacific (Opresko 2001), Madagascar (present study).

Figures

FIGURE 29. Cupressopathes cf. pumila INV.131366. (a) In situ pictures of the whole colony (b) In situ close-up view of a primary pinnule. (c) Detailed view of the branching pattern and the pinnulation of a distal branch. (d) Cross section of a distal branch showing the arrangement of the primary pinnules in four irregular rows. (e–f) Detailed top views of the pinnulation of two primary pinnules showing the biserial arrangement of the subpinnules and the variation in their density. (g) Section of subpinnule 0.13 mm in diameter, polypar side is on the right. (h) Section of primary pinnule 0.25 mm in diameter, polypar side is on the right. (i–j) Sections of two branches 0.30 mm and 1.30 mm in diameter, respectively. (k) Abpolypar spine of subpinnule. (l) Polypar spine of subpinnule. (m) Polypar spine on primary pinnule. (n) Tall, acicular and needle-like spines occurring on thick branch.

FIGURE 30. Cupressopathes pumila (Brook, 1889) type specimen. (a) Entire colony, holotype Brit. Mus. 83.9.13.15. (b) Schizoholotype USNM 100355 showing different sections of 0.08, 0.11, 0.12 and 0.22 mm in diameter, respectively.