Bathypathes galatheae Pasternak, 1977

Lima, Manuela M., Cordeiro, Ralf T. S. & Perez, Carlos D., 2019, Black Corals (Anthozoa: Antipatharia) from the Southwestern Atlantic, Zootaxa 4692 (1), pp. 1-67 : 38-40

Bathypathes galatheae Pasternak, 1977

Figs 19 , 20

Bathypathes galatheae Pasternak, 1977: 159–160 ; fig: 2;

Bathypathes galatheae: Opresko, 2002: 416 .

Type and type locality. Institute of Oceanology (specimen not traced), Russian Academy of Sciences, Moscow, Rússia; Panamá, 5º43’58.8”N, 79º19’58.8”W, 2950–3190 m .

Material examined. Brazil, Bacia de Campos; Zona 24 K . Depth.: 755 m. Alcohol 95%, on Enallopsammia rostrata and with associated ophiuroid. Date: 18/03/2006; Col.: T. Conqueror. Projet: Cap. B.C. Barracuda ( MNRJ 7934 , 1 specimen) .

Diagnosis. Corallum monopodial and robust. Pinnules straight and arranged bilaterally and suboppositely on the stem. Distance between the pairs of pinnules increases towards the top of the corallum. Spines triangular, slightly compressed laterally, sharp and smooth. Longest spines situated on the polyp-bearing surface and up to 0.26 mm tall. Abpolypar spines 0.08–0.15 mm tall. Mutual distance between spines of one row extremely variable, from 0.4–1.1 mm. Polyps large, elongated in the direction of the axis of stem and branches (4.5–7 mm in transverse diameter), with a prominent oral cone (adapted from Pasternak, 1977).

Description of Brazilian specimen. Corallum monopodial, unbranched and pinnulate, with two rows of pinnules arising on the stem in subopposition ( Fig. 19 a–b). Colony 17.13 cm high, 21.69 cm wide, with pinnules appearing at 2.75 cm from the base. Stem thickness of 1.68 mm. Length of pinnules up to 130 mm. Distance between pinnules of the same row 5.5–8.5 mm, but more common about 6 mm, along the entire length of the corallum. Basal diameter of the pinnules between 0.65 and 0.9 mm. Angle between pinnules of opposite rows between 70° and 110°. Spines on the pinnules in approximately 6 rows ( Fig. 19c ). Spines triangular, acute, smooth ( Fig. 19d ), occasionally with bifurcated apex. Polypar spines on the pinnules 0.090 –0.180 mm high, but more common about 0.12–0.16 mm; abpolypar spines 0.067 –0.100 mm. Width at the base of the spines between 0.077 and 0.200 mm, most common being close to 0.097 mm. Distance between spines in the same row from 0.3 to 0.8 mm, with a density of 2 to 4 spines per millimeter in each row. Polyps 5–6.5 mm in transverse diameter.

Remarks. According to Pasternak (1977), B. galatheae differs from all species contained in the genus mainly due to its large spines, reaching up to 0.26 mm. Although the spines of the specimen studied here reach up to 0.18 mm, this value is already considered high for the other species of Bathypathes ( Brook, 1889; Opresko, 2002; Opresko, 2005). Besides having larger spines, the specimen described here differs from B. platycaulus Totton, 1923 by having subopposite pinnules., and it differs from B. patula Brook, 1889 by having longer pinnules [up to 13 cm vs. 7.5 cm in the type of B. patula ), and larger spines (up to 0.18 mm vs. ≤ 0.07 mm). Our specimen of B. galatheae also differs from B. bayeri Opresko, 2001 in the shape of spines. In present study, the samples show triangular and simple spines, whereas in B. bayeri they are multiply knobbed at the apex ( Opresko, 2005). Pasternak (1977) describes abpolypar spines in the type of B. galatheae with sizes between 0.08 and 0.15 mm, similar to that observed here (0.067 to 0.1 mm). The type material, according to Pasternak (1977), was quite damaged, with no apical portion and no basal disc, and with broken pinnules, except for one 130 mm long and another 142 mm long. In relation to the abnormally large polypar spines in the type described by Pasternak (1977) (up to 0.26 mm), the holotype is a colony with fractured pinnules followed by regenerations. According to Molodtsova (2016), regeneration may cause spines on the remaining axis to grow abnormally large as new layers of sclerenchyme are added. Thus, it is possible to infer that the smaller spines of the material studied here fall within the intraspecific variation of the taxon. Here is the first record of the species Bathypathes galatheae for the South Atlantic, and the first record of the genus for the continental slope of Brazil.

Distribution. Gulf of Panamá (Pasternak, 1997) and Southwestern Atlantic, Brazil, Bacia de Campos (this work) ( Fig. 20 ); from 755 m (this work) to 3190 m ( Pasternak, 1977).

Figures

FIGURE 19. MNRJ 7934: Bathypathes galatheae Pasternak, 1977. a—Corallum morphology; b—Pinnulation pattern; c—Organization of spines; d—Spines magnified.

FIGURE 20. Geographic distribution of Bathypathes galatheae Pasternak, 1977. Yellow circles: records extracted from the literature (Pasternak, 1977) and based on Ocean Biogeographic Information System (OBIS). Red circle: record made in the present work.