Tanacetipathes thamnea ( Warner, 1981 )

Assis, José Eriberto De, de Souza, José Roberto B., de Lima, Manuela M., de Lima, Gislaine V., Cordeiro, Ralf T. S. & Pérez, Carlos D., 2019, Association between deep-water scale-worms (Annelida: Polynoidae) and black corals (Cnidaria: Antipatharia) in the Southwestern Atlantic, Zoologia (e 28714) 36, pp. 1-13 : 9

Tanacetipathes thamnea ( Warner, 1981)

Figs 25–27

Antipathes thamnea Warner, 1981: 148–151 , figs. 2–4. Tanacetipathes paula Perez, Costa and Opresko, 2005:8–12 , figs 5–8.

Description. Colonies 8–25 cm long, in bottlebrush pattern, monopodial, with branches absent or branching to second order, near colony base ( Fig. 25). Primary pinnules usually arranged in four rows. Primary posterior pinnules 10–18 mm long (more common 14–16 mm), larger than the anterior ones (3–12 mm long, varying in juvenile colonies). Secondary pinnules tipping toward distal end of primary pinnule. 7–20 (more commonly 10–15) secondary pinnules per posterior primary pinnule ( Fig. 26), 2–12 mm long. Tertiary pinnules scarce, usually more abundant on abpolipar side of posterior primary pinnule, 1–4 per posterior secondary pinnule. Angle between posterior and anterior primary pinnule (polypar and abpolypar sides, respectively) 55º–70°. Angle between two anterior or two posterior primary pinnules (polypar/polypar sides or abpolypar/ abpolypar, respectively) 115–130°. Abpolypar side of posterior primary pinnules with more secondary pinnules than polypar side. Spines smooth, with few ornaments, slightly inclined toward distal end of pinnule or branch ( Fig. 27). Distance between spines mainly 0.12–0.18 mm. Polypar spines 0.1–0.2 mm long; Abpolypar spines 0.036 –0.084 mm long. Polyps not seen (lost tissue).

Material examined. MOUFPE-CNI 350, 04°44”31’S; 36°26’ 19”W, 101–108 m (Potiguar Basin).

Distribution. Boca de Navios, NW Trinidad ( Warner 1981), Gulf of México ( Opresko 2009), and Brazilian coast ( Loiola and Castro 2005, present study), 30 to 108 m depth. This is the first record of the species for the Potiguar Basin, Brazil.

Remarks. Our specimens differ from the syntype described by Warner (1981) in some characters. They were slightly shorter (up to 25 cm long versus 20–40 cm long). Some colonies had posterior primary pinnules more elongated and with more secondary pinnules than that described by Loiola and Castro (2005). Warner (1981) also noted that there may be 5–10 secondary pinnules per posterior primary in a 10 mm primary pinnule, considering that a pinnule may reach up to 25 mm. Moreover, Loiola and Castro (2005) found 1–2 tertiary posterior pinnules per posterior secondary whereas our specimens had 1–4. Also, Warner (1981) mentioned a few distally inclined tertiary pinnules. Outnumber primary pinnules may occur especially in the more distal regions of the colonies as well as in larger colonies. Warner (1981) mentioned the presence of errant polychaetes in almost all colonies, living in a kind of tube formed by pinnules on the side of the colony turned toward the sea current.