Parantipathes Brook, 1889

Opresko, Dennis M. & Molodtsova, Tina N., 2021, New species of deep-sea Antipatharians from the North Pacific (Cnidaria: Anthozoa: Antipatharia), Part 2, Zootaxa 4999 (5), pp. 401-422 : 415-416

Parantipathes Brook, 1889

partim Parantipathes Brook, 1889: 141 ; van Pesch 1914: 96.

Parantipathes, Opresko 2002: 435–437 ; Pasternak 1977: 160–161; Molodtsova & Pasternak 2005: 170; Molodtsova 2006: 142; Brugler et al. 2013: 318; Bo et. al. 2014: 115; Opresko 2015: 157.

partim Bathypathes, Pasternak 1958: 187 .

not Bathypathes Brook, 1889: 151 .

Diagnosis. Corallum monopodial to sparsely branched, stem and branches pinnulate. Pinnules simple, arranged in at least six axial rows, and in alternating semispiral groups of three or more on either side of the axis. Spines usually simple (rarely with apical lobes), triangular or conical, acute, and often laterally compressed. Polyps mostly 1.6 to about 3 mm in transverse diameter.

Type species. Antipathes larix Esper, 1790

Remarks. The genus Parantipathes is very close morphologically to Lillipathes in that species in both genera have simple pinnules arranged bilaterally in axial rows, and also in alternating groups in which the members of the group are slightly offset such that they follow a semispiral pattern. The main difference between the two genera is that in Parantipathes there are typically three or more pinnules per group, which is equivalent to three or more axial rows on each side of the stem and branches (when present); whereas in Lillipathes there are no more than two pinnules per group, equivalent to a maximum of four rows of pinnules (two on each side). However, in species of Parantipathes there are only four rows of pinnules on the lower parts of the corallum, increasing to six or more rows (groups of three or more) on the upper parts. This means that if a juvenile colony or if only a developing branch of a colony is collected that has only four rows of pinnules, it could easily be misidentified as Lillipathes . Currently there is no other taxonomic character that clearly separates these two genera. In DNA sequencing studies using the mt gene regions nad5-nad1 and cox3-cox1 the two genera were not separable ( Brugler et al. 2013); however, additional mitochondrial and nuclear markers need to be evaluated.

Species assigned to the genus. Parantipathes dodecasticha Opresko, 2015 , Bathypathes euantha Pasternak, 1958 , Parantipathes helicosticha Opresko, 1999 , Parantipathes hirondelle Molodtsova, 2006 , Parantipathes laricides van Pesch, 1914 , Antipathes larix Esper, 1790 , Parantipathes robusta Opresko, 2015 ; Antipathes tetrasticha Pourtalès, 1868 , Parantipathes wolffi Pasternak, 1977 , and Parantipathes pluma n. sp.

Distribution. The genus has been found in the Atlantic, Pacific and Indian Ocean at depths of 120–1872 m; however, recent genetic studies conducted on samples from both the Pacific and Atlantic indicate that, based on mt cox3-cox1 and nad5-nad, the species in the two ocean basins fall into two separate clades ( Chery et al. 2018).