Evolution and phylogeny of glass-sponge-associated zoantharians, with a description of two new genera and three new species
Author
Kise, Hiroki
Author
Montenegro, Javier
Author
Santos, Maria E. A.
Author
Hoeksema, Bert W.
Author
Ekins, Merrick
Author
Ise, Yuji
Author
Higashiji, Takuo
Author
Fernandez-Silva, Iria
Author
Reimer, James D.
text
Zoological Journal of the Linnean Society
2022
2021-09-29
194
323
347
journal article
2865
10.1093/zoolinnean/zlab068
992a1126-487d-4ac6-b5c7-e83590fea7bd
0024-4082
5799592
5CBBACDD-0A2D-4F22-A732-0CD2D5E3D9AD
EPIZOANTHUS
AFF.
ARMATUS
CARLGREN, 1923
(
FIG. 3E
)
Material examined:
MISE-HPD1323 (NSMT-Co 1759),
Kuroshima Island
,
Kagoshima
,
Japan
,
24°13
′
36.1
″
N
,
124°06
′
18.0
″E
, depth
468 m
, ROV, coll.
J. D. Reimer
on RV
Natsushima
,
19 Sep 2011
, fixed in 90% ethanol
.
Description: External morphology
. Circa 80 cylindrical polyps connected by strongly developed light-brownish coenenchyme on stalks of hexactinellid sponges (
Hyalonema
sp.
) in preserved specimen. Colony covered the upper part of the stalks, but not around the spiculous anchor. Contracted preserved polyps well developed and
0.5–4.9 mm
in height,
2.5–7.8 mm
in diameter.Capitulary ridges present but weakly pronounced when contracted,
c
.
14–16 in
number. The numbers of tentacles of each polyp
c.
28–32 and tentacles arranged in two rows.
Internal morphology
. Zooxanthellae absent. Number of mesenteries 28–32, in macrocnemic arrangement. Reticulate mesogleal musculature.
Habitat and distribution:
Off Kuroshima
,
Okinawa
, in the
Ryukyu Archipelago
,
Japan
at a depth of
468 m
.
Epizoanthus armatus
has previously been reported from off
Somalia
in the Indian Ocean (
Carlgren, 1923
).
Figure 3.
Images of preserved
Amphidiscophora
spongesassociated zoantharians. A, B,
Epizoanthus fatuus
collected from Japan; C,
Epizoanthus
aff.
fatuus
collected from Australia; D,
Epizoanthus stellaris
collected from Australia; E,
Epizoanthus
aff.
armatus
collected from Japan. Scales: 10 mm.
Associated host:
Hyalonema
sp.
Remarks:
Polyp dimensions of the examined specimen are larger than those of
E. fatuus
and
E. stellaris
, and this specimen resembles
E. armatus
as described by
Carlgren (1923)
. The morphological characters and dimensions observed in the examined specimen agree well with the original description by
Carlgren (1923)
.
Epizoanthus armatus
was originally described from East Africa (
Carlgren, 1923
).
Kise
et al.
(2018)
reported the existence of
E. planus
Carlgren,
1923
in Japanese waters, and this species was also originally described from East Africa.Therefore, it is possible that
E. armatus
may also be distributed in Japanese waters. However, the collected depths of the examined specimen in this study and the specimens
Carlgren (1923)
examined are different (
468 m
vs.
741–1362 m
deep). We also could not observe internal morphology of the examined specimen due to its poor preserved condition. Therefore, we here preliminarily identified the examined specimen as
Epizoanthus
aff.
armatus
. Examination of additional specimens combined with molecular analyses should help confirm the identity of this specimen.