Bryopesanser ascendosolaris Tilbrook, 2012

Yang, Ho Jin, Seo, Ji Eun & Gordon, Dennis P., 2018, Sixteen new generic records of Korean Bryozoa from southern coastal waters and Jeju Island, East China Sea: evidence of tropical affinities, Zootaxa 4422 (4), pp. 493-518 : 504-505

Bryopesanser ascendosolaris Tilbrook, 2012

(Figs 19–21)

Escharina pesanseris: Harmer 1957: 998 (part).

Bryopesanser ascendosolaris Tilbrook, 2012: 53 , figs 32–34. Material examined. One colony (NIBRIV00000805888), Munseom Island , Jeju, 20 m, collected by Ho Jin Yang.

Description. Colony encrusting, multiserial, unilaminar, white, up to 7 mm across. Autozooids variably subelongate-rectangular, widening or narrowing proximally, with distinct boundaries. Frontal shield opaque, imperforate in older zooids owing to thin layer of secondary calcification; neanic zooids at margin evenly and densely perforated by 100 or more tiny pseudopores. Orifice very much longer than wide, distally arched, parallelsided, proximal rim straight with right-angled proximolateral corners; long, narrow, ridged condyles occupy entire rim either side of deep, narrow sinus. Seven oral spines.

Avicularia always paired, each adjacent to latero-oral spines, incurved, with triangular rostrum and complete crossbar. Mandible with V-shaped sclerite; one arm may have short branch between the two longer arms.

Ooecium relatively short, set somewhat distally such that entire orifice can be seen, skeletal surface smooth with crescentic flattened area proximofrontally. Six oral spines present in ovicellate zooids.

Interzooidal communication via mural septula. Ancestrula not seen.

Measurements. ZL 440–633 (552) µm; ZW 311–477 (375) µm; OrL 43–74 (56) µm; OrW 54–73 (61) µm; AvL 50–77 (62) µm; AvW 30–45 (40) µm; OoL 91–127 (105) µm; OoW 171–192 (183) µm.

Remarks. This species has been seen only once before. Tilbrook (2012) separated it from material examined by Harmer (1957) from an indeterminate locality in Japan. The sole specimen (holotype) comprises only nine zooids (some not whole), but the characters are distinctive and the present specimen accords with Tilbrook’s description. It remains to be seen if Mastigophora dutertrei var. japonica Ortmann, 1890 from Sagami Bay is conspecific with B. ascendosolaris or represents a second species from Japan. It also has seven oral spines.

Distribution. Japan: locality uncertain. Korea: Jeju Island, 20 m depth.