Anthoptilum lithophilum, Williams, Gary C. & Alderslade, Philip, 2011

Williams, Gary C. & Alderslade, Philip, 2011, Three new species of pennatulacean octocorals with the ability to attach to rocky substrata (Cnidaria: Anthozoa: Pennatulacea), Zootaxa 3001, pp. 33-48: 36-38

publication ID 10.5281/zenodo.200521

persistent identifier

treatment provided by


scientific name

Anthoptilum lithophilum

sp. nov.

Anthoptilum lithophilum   sp. nov.

Figs. 2 –3 View FIGURE 2 , 6 View FIGURE 6 C, 8 D, 10

Material examined. HOLOTYPE: CAS 179453, sample number T 666 -R 10, California, Northeast Bank, Outer California Borderlands, 32.2716305 ° N, 119.6724745 ° W, 669 m depth, 3 May 2004, MBARI, on basaltic lava.

PARATYPE: CAS 179454, sample number T 628 -A 4, California, Rodriguez Seamount, 34.057368 ° N, 121.052983 ° W, 700 m depth, 14 October 2003, MBARI, on volcaniclastic pavement. OTHER: CAS 179456, Anthoptilum   sp. indet., Hawai’i, Niihau, 21 ° 59.250 ’N, 160 ° 12.631 ’ W, Site: NW- 1 c, 368 m depth, 3 May 2010, HURL, one damaged specimen.

Diagnosis. Ratio of total colony length to rachis diameter approximately 50: 1. Autozooids 10–15 mm long, 2– 4 mm wide. Adjacent autozooids closely placed in indistinct, slightly oblique rows. Autozooid walls with minute oval sclerites, each usually less than 0.01 mm in length. Proximal terminus of peduncle modified into a markedly widened structure with a protruding, conical, terminal knob covering the end of the axis.

Description. The holotype ( Fig. 2 View FIGURE 2 A) is 118 mm long with the polyp-bearing rachis occupying 98 mm (or 83 %) of the entire length. Approximately 45 autozooids are arranged along the length of the rachis, which are 9–16 mm long and not readily discernible as biserial, opposite, sub-opposite or alternate, being more randomly placed. In one 10 mm long autozooid, the polyp wall is 7 mm long, while tentacle length is 3 mm. Siphonozooids are conspicuous, approximately 0.3–0.4 mm in diameter, and appear as white hemispherical protuberances arranged in several longitudinal rows on both sides of each longitudinal row of autozooids. Sclerites are scattered, minute oval bodies, less than or equal to 0.01 mm long, present only in the body walls of the autozooids ( Fig. 3). The rachis of the preserved specimen is grayish-white and the autozooids are tan.

Variability. The paratype is 95 mm long with a mauve rachis/peduncle and dark purplish-brown autozooids.

Etymology. The specific epithet lithophilum   is derived from the Greek (lithos —stone) and (philos —loving, fond of, having affinity for), alluding to this species inhabiting rocky substrata.

Distribution. Presently known only from off the coast of California, U.S.A.; 669–700 m in depth ( Fig. 10 View FIGURE 10 ).

Differential diagnosis. Anthoptilum lithophilum   sp. nov. has sclerites in the polyp walls but these are lacking in all other species of the genus. The ratio of colony length to rachis diameter is 50: 1, but the ratio in the other species is as follows: A. grandiflorum   , up to 100: 1; A. murrayi ( Kölliker, 1880)   , 93: 1; A. decipiens   sp. nov., 180: 1; A. gowlettholmesae   sp. nov., up to 30: 1.

Remarks. One damaged, additional specimen collected from Niihau, Hawai’i ( CAS 179456), is considerably laterally compressed and significantly flattened. Although it does show a superficial resemblance to Anthoptilum lithophilum   sp. nov., its identification remains uncertain.


California Academy of Sciences