Myriopathes cf. ulex ( Ellis & Solander, 1786 )

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 : 46-48

Myriopathes cf. ulex ( Ellis & Solander, 1786)

Fig. 26

Antipathes ulex Ellis & Solander 1786, p. 100 , figs. 7–8

Euantipathes ulex van Pesch 1914, p. 79 , fig. 62

Myriopathes ulex Opresko 2001, p. 349

Material examined. Toliara, 19 m. Distal branches, specimen INV.131356 .

Depth range. 15–30 m.

Description. The colony is branched and measures about 50 cm in height ( Fig. 26 , a). The individual fronds of the colony are planar and flabellate, and the colony appears dark brown ( Fig. 26 , a, b). The primary pinnules measure up to 1 cm, after which they become incipient branches, and are regularly inclined 30–45° to the branch; they are mainly biserial alternate ( Fig. 26 , b, c). In each row the primary pinnules are 1.0–2.0 mm apart, with an average of 1.5 mm. There are generally 10–12 primary pinnules occurring along one cm of branch, counting those in both lateral rows. Up to four secondary pinnules can be found but not on all primary pinnules. Secondary pinnules are usually uniserial but a biserial arrangement is sometimes found ( Fig. 25 , c). They measure 1.5–4.0 mm long and are inclined 30–45° with respect to the primary pinnule bearing them. Tertiary pinnules are usually not present, but one can be rarely found. The polyps are located on a single side of the pinnules, but on thicker branches they can be spaced irregularly all around the axis. Polyps are slightly elongated in transversal direction and measure 0.4–0.9 mm in transverse diameter. Polyps are spaced 0.08–0.44 mm apart for about 10–12 per cm. The tentacles are short, thick and rounded at the apex. The spines on the pinnules are conical to horn-shaped, slightly papillose with the papillae elongated towards the tip of the spine ( Fig. 26 , d–f). They are longer on the polypar side although it is not always the case on small subpinnules. On a secondary pinnule measuring 0.12 mm in diameter, 3–4 longitudinal rows of spines are seen ( Fig. 26 , d). The polypar and abpolypar spines are not differing in size on such pinnules ( Fig. 26 , h), both measuring up to 0.17 mm in height with mutual distances of 0.1–0.19 mm and 0.1–0.22 mm, respectively. On a primary pinnule measuring 0.14 mm ( Fig. 26 , e), 4–5 longitudinal rows are seen where the polypar spines measure up to 0.17 mm ( Fig. 26 , i) and the abpolypar spines up to 0.16 mm, with mutual distances of 0.1–0.19 mm and 0.1–0.26 mm, respectively. All these spines are inclined upwards. The spines become more numerous and cylindrical as the axis gets thicker, with the longitudinal rows being lost ( Fig. 26 , f, g, j). They tend to become perpendicular to the corallum. On branches with diameters of 0.34–1.8 mm the spines are needle-like and slightly papillose, with the papillae elongated towards the tip of the spine ( Fig. 26 , j). Bifid or antler-shaped spines are also found ( Fig. 26 , k). On these branches there is no distinction between polypar and abpolypar spines. They measure 0.1–0.26 mm in height, and the mutual distance cannot be calculated as the arrangement in longitudinal rows is lost.

Taxonomic remarks. The type specimen originally described by Ellis & Sollander (1786) is lost. It was very succinctly described as being “very much branched, with loose, spread, very rough and pointed branches”. The drawings show small primary pinnules, with sparse small single secondaries pinnules. Later descriptions were made by Brook (1889) and van Pesch (1914). Brook (1889) stated that the pinnules were subalternate, directed anteriorly, occasionally simple but usually alternately pinnate or bipinnate, and measuring 1.8 to 2.5 cm in length. Van Pesch (1914) reported branches from 0.5 to 2.5 cm long inserted with an angle of 60°. Tertiary pinnules are absent and fusions do not occur. Based on the recent revision of Opresko (2001), this species groups in the flabellate Myriopathes , together with M. ulex , M. panamensis , M. stechowi , M. spinosa , M. rugosa and M. myriophylla . It can be provisionally separated from the other species, based on a less dense pinnulation due to a lower number of subpinnules with a more planar arrangement. In the typical M. ulex , secondary pinnules are rather sparse and usually only one is found per primary pinnule, while there are usually no tertiaries. Due to the differences in the number of secondaries, the name M. cf. ulex is attributed here.

Distribution. Indonesia (type locality, Ellis & Solander 1786), Indian Ocean ( Lamouroux 1816), Philippines ( Gray 1857), Korea ( Moon & Song 2008), Hawaii ( Wagner 2015a), Madagascar (present study).

Figures

FIGURE 25. Myriopathes cf. stechowi (Pax, 1932) INV.131335. (a) Entire colony in situ. (b) Close-up view of the branching pattern in situ. (c) Detailed view of the pinnulation. (d) Section of subpinnule 0.1 mm in diameter, polypar side is on the right. (e) Section of primary pinnule 0.14 mm in diameter, polypar side is on the right. (f) Section of a branch 1.1 mm in diameter, showing numerous antler-shaped spines. (g) Polypar spine on primary pinnule. (h) Abpolypar spine on primary pinnule. (i) Antler-shaped spine on a branch. (j) Detailed view of the numerous bifid and antler-spines of a branch.

FIGURE 26. Myriopathes cf. ulex (Ellis & Solander, 1786) INV.131356. (a) In situ picture of the entire colony. (b) In situ close-up view of a branch and the primary pinnules. (c) Close-up view showing the pinnulation in details. (d) Section of secondary pinnule 0.12 mm in diameter. The polypar side is on the right. (e) Section of primary pinnule 0.14 mm in diameter. The polypar side is on the right. (f) Section of distal fragment of the main branch bearing primary pinnules and measuring 0.25 mm in diameter. (g) Section of thicker branch 0.34 mm in diameter and bearing primary pinnules. (h) Polypar spine from secondary pinnule. (i) Polypar spine from primary pinnule. (j) Tall, needle-like spine of a branch. (k) Branched, bifid or antler-like spines occurring on a branch measuring 1.8 mm in diameter.