On a collection of hydroids (Cnidaria, Hydrozoa, Hydroidolina) from the west coast of Sweden, with a checklist of species from the region 3171
Author
Calder, Dale R.
text
Zootaxa
2012
2012-01-24
3171
1
1
77
https://biotaxa.org/Zootaxa/article/view/zootaxa.3171.1.1
journal article
10.11646/zootaxa.3171.1.1
11755334
5247704
Racemoramus panicula
(G.O.
Sars, 1874
)
,
comb. nov.
Fig. 24
Campanulina panicula
G.O.
Sars, 1874: 121
, pl. 5, figs. 9–13.—
Kramp, 1941: 4
, fig. 5.—
Rees & Rowe 1969: 17
.—
Jägerskiöld, 1971: 61
.—
Cornelius, 1995a: 192
, fig. 43D.
Type
locality.
Norway
:
Oslofjord
, 50–60 fm (
91–110 m
) (G.O.
Sars 1874: 121
)
.
Museum material.
Kosterhavet,
58°53.093’N
,
11°05.668’E
,
20–30 m
,
09.ix.2010
, biological dredge,
R
/
V
Nereus
, two colonies or colony fragments, each with many hydrocauli, up to 3.8 cm high, on polychaete tubes and ascidians, without gonophores,
ROMIZ
B3916
.
Remarks.
Kramp (1941)
provided a thorough description of
Opercularella panicula
(G.O.
Sars, 1874
)
based on specimens from
Norway
and
Sweden
, and remarked on its similarity to
Campanulina denticulata
Clarke, 1907
from deep waters of the eastern tropical Pacific (
Clarke 1907
) and Sagami Bay,
Japan
(
Stechow 1913
).
Leloup (1974)
discounted seeming differences between the two as ecologically induced and regarded them as conspecific.
Vervoort (1966)
referred
Campanulina indivisa
Fraser, 1948
, from bathyal depths off California, to the synonymy of
O. denticulata
.
Subsequent authors have mostly agreed that these are all synonyms. Nevertheless, their combined range is so extensive that it raises doubts whether a single species is represented. In addition to records in the eastern Atlantic (e.g.,
Cornelius 1995a
, as
Campanulina panicula
), similar hydroids have been reported from deep waters in the western Pacific (
Stechow 1913
: as
Campanulina denticulata
;
Hirohito 1995
: as
Opercularella panicula
;
Schuchert 2003
: as
Campanulina panicula
), the eastern Pacific (
Clarke 1907
: as
Campanulina denticulata
;
Fraser 1948
: as
Campanulina
(?)
indivisa
;
Leloup 1974
: as
Opercularella panicula
), and the Indian Ocean (
Vervoort 1966
: as?
Opercularella denticulata
).
Schuchert (2003)
reported that materials from
Indonesia
were indistinguishable from those examined earlier from
Iceland
(
Schuchert 2001a
), supporting the hypothesis that a single species is represented. Its bathymetric range is also reported as being astoundingly wide, from
20–30 m
(this study) to
5200 m
(
Stechow 1913
, as
Campanulina denticulata
). As noted above, I prefer on zoogeographic grounds to keep the Atlantic
R. panicula
distinct from the Indo-Pacific
R. denticulata
.
This hydroid seems to be quite frequent in the Oslofjord, its
type
locality, having been collected at 12 stations there by
Christiansen (1972)
. Records of
R. panicula
from Swedish waters are all from the Skagerrak (see Checklist). It was not recorded in Danish waters by
Kramp (1935b)
. Of five figures of the species in the paper by
Kramp (1941)
, only one (
Fig. 5
) was based on material from
Sweden
.
Reported distribution.
West coast of
Sweden
.—Säcken Reef (
Rees & Rowe 1969
, as
Campanulina panicula
) to Skagerrak off Grebbestad (
Kramp 1941
, as
Campanulina panicula
).
Elsewhere.—Northeast Atlantic from Trondheimfjord,
Norway
(
Storm 1882
, as
Campanulina panicula
), and
Iceland
(
Schuchert 2000
,
2001a
, as
Campanulina panicula
), to
Morocco
and southern Africa (
Ramil & Iglesias 1988
, as
Opercularella panicula
;
Cornelius 1995a
, as
Campanulina panicula
).