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
Clytia gigantea
(
Hincks, 1866
)
Figs. 46
, 47
Campanularia gigantea
Hincks, 1866: 297
.—
Jäderholm, 1909: 69
, pl. 7, figs. 1–3.
FIGURE 46.
Clytia gigantea
: two hydrothecae, ROMIZ B3917. Scale equals 0.5 mm.
FIGURE 47.
Clytia gigantea
: gonotheca, ROMIZ B3917. Scale equals 0.5 mm.
Type
locality.
UK
: Scotland,
Lamlash Bay
(
Hincks 1866: 297
)
.
Museum material.
Kosterhavet,
58°53.093’N
,
11°05.668’E
,
20–30 m
,
09.ix.2010
, biological dredge,
R
/
V
Nereus
, on tube of polychaete, one colony, up to 2.2 cm high, with gonothecae,
ROMIZ
B3917
.
Remarks.
This nominal species has sometimes been combined with
Clytia hemisphaerica
(
Linnaeus, 1767
)
.
Cornelius (1982)
considered them identical, and a number of recent authors, including me (
Calder, 1991
;
Cairns
et al
. 2002
), adopted that opinion. After examining the material above, however,
Clytia gigantea
(
Hincks, 1866
)
is upheld as a valid species based on a combination of characters including its strikingly robust colony form, sparingly branched pedicels, and exceptionally large, elongate, gradually tapered hydrothecae. Moreover, hydrothecal cusps in
C.
gigantea
are linguiform (
Fig. 46
) rather than wavy as in
C. hemisphaerica
. Specimens studied here were much like those reported earlier from Bohuslän by
Jaderholm (1909
: pl. 7, figs. 1–3). In reporting the species from the Oslofjord,
Norway
,
Christiansen (1972)
noted that some hydrothecae in his material reached
3 mm
long. Ones exceeding
2 mm
in length were observed on the hydroid colony reported herein from Kosterhavet.
Reports of
Clytia gigantea
from the Mediterranean, and from the Atlantic and Pacific coasts of North America (see below), need confirmation. The species, or a variant of it, has also been reported from
Chile
(
Leloup 1974
;
Galea
et al
. 2009
).
FIGURE 48.
Clytia hemisphaerica
: part of colony with hydrotheca and gonotheca, ROMIZ B3930. Scale equals 0.5 mm.
FIGURE 49.
Gonothyraea loveni
: part of colony with two hydrothecae, ROMIZ B3885. Scale equals 0.5 mm.
Gonophores of this species, examined here (Fig. 47), are previously unknown in Europe. Those of the variant form from
Chile
have been described and illustrated by
Leloup (1974)
and
Galea
et al.
(2009)
.
Reported distribution.
West coast of
Sweden
.—Bohuslän (
Jäderholm 1909
, as
Campanularia gigantea
).
Elsewhere.—Boreal waters of the North Atlantic from
Norway
to
Great Britain
in Europe (
Hincks 1868
;
Christiansen 1972
), and from Newfoundland to Cape Cod in North America (
Fraser 1944
); questionable records exist from the Mediterranean (e.g.,
Pieper 1884
;
Babić 1904
), the Queen Charlotte Islands in the northeast Pacific (
Fraser 1937
, as
Campanularia gigantea
), and
Chile
(
Leloup 1974
;
Galea
et al
. 2009
).