Ceramaster Verrill, 1899

Mah, Christopher L., 2024, New genera and species of deep-sea Goniasteridae (Asteroidea) from the North Pacific, Zootaxa 5543 (4), pp. 451-500 : 461-462

Ceramaster Verrill, 1899

Tosia (Ceramaster) Verrill, 1899: 161

Ceramaster Fisher, 1906: 1054 ; 1911: 162, 204; Verrill, 1914: 289; Koehler, 1924: 173; Mortensen 1927: 80; Djakonov, 1950: 38; Tortonese & A.M. Clark, 1956: 347; Halpern, 1970b: 62; 1970a: 212; Downey, 1973: 49; McKnight, 1973: 178; Downey, 1973: 49; A.M. Clark & Courtman-Stock, 1976: 61; Clark & Downey, 1992: 231; Downey in Clark & Downey, 1992: 231; Mah, 2011:5, 2016: 112.

Philonaster Koehler, 1909: 78 [type species Pentagonaster (Philonaster) mortenseni Koehler, 1909 ].

Tosiaster Verrill, 1914: 1054 .

Diagnosis (Modified from Clark & Downey 1992; Mah in review)

Body outline pentagonal in most (i.e., R/r=1.1–1.5) with some becoming more stellate.Abactinal plates strongly tabulate, granules present on abactinal plates, marginals, actinal plates. Fasciolar grooves well developed, present among abactinal, and marginal plates. Bare “patch” on dorsal facing of superomarginal plates.

Comments

Ceramaster includes 16 accepted extant and 4 fossil species ( Mah 2024b), which occur throughout all of the world’s oceans, including several in the North Pacific ( Fisher 1911). The most recent of these, Ceramaster vorax was described from Johnston Atoll ( Mah 2020).

The diagnosis follows a current account of Ceramaster and related genera (Mah, in press). The taxonomic difficulties in Ceramaster and related genera, such as Peltaster and Sphaeriodiscus have been outlined elsewhere (e.g. Mah 2018, and MS in press). For the purposes of species described herein, the definition is restricted to those taxa which most closely resemble the typological Ceramaster granularis , specifically including Ceramaster patagonicus . The use of Ceramaster here specifies a combination of characters shared by C. granularis , the related C. patagonicus , and other similar Ceramaster species, but excluding Ceramaster grenadensis and related species, such as Ceramaster pointsurae Mah 2016 which are assigned to a new genus, currently in description. Thus, treatment herein disagrees with the assignment of Ceramaster patagonicus as a subspecies of Ceramaster grenadensis as outlined by Clark & Downey (1992).

Observed species, such as C. vorax , which is similar to C. patagonicus , have been observed in situ as predators on sponges ( Mah 2022) and/or feeding on encrusting organisms or detritus on the substratum. This is similarly observed in the Atlantic Ceramaster granulari s ( Gale et al. 2013).