Sixteen new generic records of Korean Bryozoa from southern coastal waters and Jeju Island, East China Sea: evidence of tropical affinities
Author
Yang, Ho Jin
Author
Seo, Ji Eun
Author
Gordon, Dennis P.
text
Zootaxa
2018
4422
4
493
518
journal article
30030
10.11646/zootaxa.4422.4.3
d2c5d8c4-d2e2-44a7-add4-3a94812d2581
1175-5326
1253219
45E16185-7EE6-4768-88DF-6ACA1D29DCE4
Calloporina hayamiae
Arakawa, 1995
(Figs 26, 27)
Calloporina sculpta
:
Nishizawa 1990
: 119
, pl. 4, fig. 3.
Non
Calloporina sculpta
Canu & Bassler, 1929
.
Calloporina hayamiae
Arakawa, 1995
: 98
, fig. 9A.
Material
examined.
Unique
colony (NIBRIV00000805890), from
Hajo Island
,
South Sea
,
30 July
2016
, 33 m, on oyster shell, collected by grab from
RV Kuklipgongwon-yeoungu
1.
Description.
Colony encrusting, multiserial, unilaminar, large, up to
77 mm
across. Autozooids fairly regularly rhomboidal, rounded distally and proximally, more acute laterally, a little longer than wide. Lepralioid frontal shield with 12–17 conspicuous areolar-septular pores around margin, with slight ribbing between pores that converges to low frontal-shield ridges of irregular disposition. Orifice high-arched; weakly concave proximal margin with low, sloping condyles in corners. Oral spines 5–6, stout. Ascopore at some distance from orifice, incised, semi-lunate, very thin, lacking denticles.
Avicularia mostly single, on left or right sides of autozooids, less often paired, rarely absent; rostrum moderately long, acute, directed mostly obliquely distolaterally, tip often projecting just beyond lateral margin, crossbar well developed; half rostral length with palatal shelf, no opesial cryptocyst.
Developing ooecium with extensive membranous area of proximofrontal ectooecium that is calcified around periphery and has apical transverse rimmed cap; endooecium skeletally complex, initially with transverse creases proximofrontally and honeycomb of calcification frontally; as development proceeds, lateral calcification of ectooecium covers most of endooecium, leaving bean-shaped or bifenestrate window showing endooecial pits, distal of which is rimmed ectooecial cap, itself sometimes etched.
Well-developed basal pore-chambers at colony margin, two distolateral, one distal, each subdivided into paired chambers. Ancestrula not seen.
Measurements.
ZL 388–524 (432) µm; ZW 295–551 (378) µm; OrL 87–108 (99) µm; OrW 91–110 (100) µm; AvL 101–158 (138) µm; AvW 39–67 (55) µm; OoL 137–166 (156) µm; OoW 153–186 (172) µm.
Remarks.
Calloporina hayamiae
was previously known only as a Pleistocene fossil from the Boso Peninsula, on the east coast of central Honshu,
Japan
. The characters of our material are identical to that described by
Arakawa (1995)
, especially the distinctive semi-lunate ‘smile-like’ ascopore incised within sloping margins, and the form of the mature ooecium.
Arakawa (1995)
noted a range of 4–6 oral-spine bases.
Calloporina hayamiae
has not yet been reported from modern Japanese waters but it is highly likely that it will be discovered.
Distribution.
Japan
: Pleistocene, east-central Honshu.
Korea
:
Jeju
Island,
20 m
depth.