Lophaster furcilliger Fisher, 1905

Mah, Christopher L. & Fujita, Toshihiko, 2020, New species and occurrence records of Japanese Solasteridae and Ganeriidae including a new species of Paralophaster from the North Pacific with an overview of Hyalinothrix, Zootaxa 4750 (1), pp. 67-100 : 73

Lophaster furcilliger Fisher, 1905

Lophaster furcilliger Fisher, 1905: 312 ; 1911: 334; Djakonov 1950: 64; Alton 1966: 1706; Oguro in Imaoka et al. 1991: 91; Kogure & Hayashi 1998: Lambert 2000: 79; Lamb & Hamby 2005: 329; Lee & Shin 2009: 331.

Lophaster furcilliger vexator Fisher, 1910: 574 ; Fisher 1911: 334; Djakonov 1968: 55.

Lophaster furcilliger vaxator (sic): Baranova 1957: 163.

Sarkaster validus Ludwig, 1905: 185 .

Diagnosis. Lophaster displaying two to five (mostly four or five) furrow spines, up to 20 spinelets per paxillae. Large size with specimens up to R=9.2.

Comments. Lophaster furcilliger is a widely occurring species along the Pacific coast of North America, extending from the Galapagos to Japan and Korea. This species was first recorded from the Sea of Japan by Oguro in Imaoka et al. (1991) with subsequent occurrence in the Sado Strait recorded by Kogure and Hayashi (1998).

Based on the relatively few spinelets on each paxillar spine, the elongate arms and the bathymetric range, species observed herein are most consistent with the type species Lophaster furcilliger rather than the “shallow water” subspecies L. furcilliger vexator . Fisher (1910,1911) designated this subspecies, L. furcilliger vexator based on larger disk, thicker rays, (and thus smaller R/r), stouter abactinal and marginal paxillae, each with six to ten fine points instead of two to four, heavier adambulacral spines and more closely placed adambulacral plates. Baranova (1957) and Djakonov (1968) regard L. furcilliger vexator as a forma of L. furcilliger and intermediate in form between the Pacific L. furcilliger and the Arctic/Atlantic L. furcifer . Fisher’s (1911: 340) account of this species refers to it as being present in “lesser depths” with distribution from the southern Bering Sea to northern California. Lambert (2000) and Lamb & Hanby (2005) have both indicated L. furcilliger vexator as the “shallow-water” subspecies. However, details as to the extent or specific occurrence are vague. Based on the case presented in the literature, L. furcilliger vexator ’s character differences are best interpreted as phenotypic variation. However, some characters such as “thicker rays” and “closely placed adambulacrals” could result from post-mortem deformation, such as in Ceramaster which shows a swollen abactinal surface in situ versus those in preserved specimens (Mah 2015).

Occurrence: Japan (Sagami Bay, Sea of Japan), Korea, Bering Sea, Okhotsk Sea, Aleutian Islands, California to Baja California and Galapagos region, 86 to 4200 m.

Material Examined. Japan. NSMT E-11363, Off Iwaki, Fukushima Prefecture, Japan, 37˚26.65′N, 142˚18.10′E– 37˚27.32′N, 142˚18.59′E, 840–866 m, Coll . R / V Soyo-maru, St. 8, 2 August 2012, 1 wet spec ., R =10.9 r=2.8; NSMT E-11340, Off Iwaki, Fukushima Prefecture, 37˚35.0′N, 142˚23.4′E–37˚37′N, 142˚23.4′E, 901–923 m, Coll . R / V Soyo-maru, St. C5-B, 21 July 2008. 9 wet spec ., R =7.5 r=2.2, R =4.6 r=0.9, R =9.6 r=2.5, R =9.2 r=2.4, R =6.4 r=2.0, R =6.5 r=1.6, R =3.0 r=4.0, R =2.3 r=0.6, R =2.4 r=0.4; NSMT E-11311, Off Soma, Fukushima Prefecture, 37˚59.21′N, 142˚33.00′E, 1165 m, Coll . R / V Soyo-maru, St. 10, 19 July 2012, 1 spec. , R =5.2 r=1.0; NSMT E-11305, Off Soma, Fukushima Prefecture, 37˚59.21′N, 142˚33.00′E, 1165 m, Coll . R / V Soyo-maru, (probably) St. 10, 19 July 2012, 9 spec. , R =7.5 r=1.7, R =7.0 r=0.9, R =5.9 r=1.2, R =3.7 r=0.9, R =4.0 r=0.9, R =4.2 r=0.6, R =5.8 r=1.2, Two specimens with all arms damaged .