Taxonomic notes on Hydroidomedusae (Cnidaria) from South China Sea I: Family Eucodoniidae (Anthomedusae)
Author
Mao Lin
Author
Zhenzu Xu
Author
Jiaqi Huang
Author
Donghui Guo
Author
Chunguang Wang
text
Zoological Systematics
2016
41
1
48
53
journal article
54615
10.11865/zs.201602
f00fc1d9-829c-4bc9-85a5-1bdc61fe805c
269256
urn:lsid:zoobank.org:pub:CE49B180-42B8-437F-89C2-77C56BBD352B
Eucodonium brevistyle
Xu, Huang & Lin, sp. nov.
(
Figs 2
,
7–8
)
Material examined.
Holotype
(
TIO 009
),
Beibu Bay of South China Sea, Station H
11
(
18
°
17
'N
,
109
°06'E
), depth
20 m
,
6
August
2006
, coll.
Donghui Guo
.
Paratype
.
Three specimens
(
TIO 010–012
), same data as holotype;
two specimens
(
TIO 020–021
),
East China Sea, Station
332
and
338
,
August
2002
.
Diagnosis. Unbrella nearly hemisphaerical, with slight rounded apical projection; gastric peduncle short and broad, shorter than the length of manubrium, manubrium cylindrical, oral tube short, about 1/2 length of manubrium, mouth quadrangular, with 4 inconspicuous perradial lips, each containing a row of numerous nematocysts; 2 opposite perradial marginal tentacles, short and thin, with ring nematocysts and a small terminal knob, marginal bulbs spherical-like, inside swelling, without ocelli, but containing red-brown pigment granules, and other 2 opposite marginal bulbs without tentacles.
Description. Umbrella nearly hemisphaerical, bell 0.9–1.0 mm in height, 0.4–0.8 mm in width, with slight rounded apical projection; jelly fairly thin; gastric peduncle very short and broad, shorter than the length of manubrium; manubrium large on broad gastric peduncle, oral tube short, about 1/2 of the length of manubrium; manubrium cylindrical, about 1/3 as long as bell cavity; mouth quadrangular, with 4 inconspicuous perradial lips, each containing a row of numerous nematocysts; medusa buds arise from interradial region of stomach; 4 very narrow radial canals and circular canal present; 2 opposite perradial marginal tentacles, short and thin, thread-like, extending to 1/3 the height of umbrella, with ring nematocysts and a small terminal knob containing nematocysts; marginal bulbs spherical-like, inside swelling, without ocelli, but containing red-brown pigment granules, and other 2 opposite perradial marginal bulbs without tentacles; velum narrow.
Distribution. Northern South China Sea (Beibu Bay), East China Sea.
Etymology. The specific name is from the Latin
brevistyle
, meaning brevi-style, referring to the short peduncle, which is shorter than the length of manubrium.
Figures 4–9.
Eucodonium
spp. 4–6.
E. bitentaculatum
Xu, Huang & Guo,
sp. nov.
7–8.
E. brevistyle
Xu, Huang & Lin,
sp. nov.
9.
E. longitentaculatum
Xu, Huang & Wang,
sp. nov.
4, 7, 9. Lateral view. 5, 8. Gonads, dorsal view. 6. Gonads, lateral view. Scale bars = 0.5 mm.
Remarks. This new species is close to
E. bitentaculatum
Xu, Huang & Guo,
sp. nov.
, but differs from the latter by following: 1) a gastric peduncle shorter than the length of the manubrium; 2) two opposite perradial marginal tentacles short and thin, thread like, terminal knob without terminates in a thin fibrous appendage; 3) oral tube short, about 1/2 length of manubrium.