Systematics and diversity of deep-water Cheilostomata (Bryozoa) from Galicia Bank (NE Atlantic)
Author
Souto, Javier
Author
Berning, Björn
Author
Ostrovsky, Andrew N.
text
Zootaxa
2016
4067
4
401
459
journal article
46900
10.11646/zootaxa.4067.4.1
4d2bf7a6-415a-4fb2-8c8f-12b79f8a400a
1175-5326
257945
1CC5D0E7-0B60-4E62-BACD-9775931ED7F9
Schizomavella fischeri
(Jullien, 1882)
(
Figs 119–125
,
Table 21
)
Schizoporella fischeri
Jullien, 1882: 15
, pl. 14, figs 32, 33; Jullien 1883: 511, pl. 14, figs 32, 33; Calvet 1907: 422.
Schizomavella fischeri
: d’Hondt 1973a: 371
; d’Hondt 1974: 40; Harmelin & d’Hondt 1992: 44, pl. 5, E-F; Reverter-Gil
et al
. 2014: 25.
Material examined.
MNCN
25.03/3981, 3982, locality
V01
;
MNCN
25.03/3983, locality DR10; OLL 2015/921, locality DR05; OLL 2015/922, locality DR10; OLL 2015/923, locality DR09.
FIGURES 119–125.
Schizomavella fischeri
:
119, 120,
parts of colonies with ovicells (respectively MNCN 25.03/3981 and OLL 2015/923);
121,
ancestrula with two distal zooids;
122,
ovicellate zooids (MNCN 25.03/3981);
123, 124,
zooidal orifices, each with a suboral avicularium (MNCN 25.03/3981);
125,
distal part of autozooid with ovicell and suboral avicularium (OLL 2015/923).
Remarks.
The description of this species was originally based on a single specimen from
1068 m
depth from the Iberian continental slope south of Galicia Bank (Jullien 1882). We have recently studied the
type
material of
S. fischeri
, as well as several additional specimens from different areas, within the scope of a revision of NE Atlantic deep-water
Schizomavella
species. A thorough description of the species has very recently been published elsewhere (Reverter-Gil
et al
. 2015). Although the morphology of the different populations varies to some extent (e.g. number of oral spines, sinus width, frontal shield ornamentation), a clear line cannot be drawn between any of these populations based on morphology alone. The Galicia Bank specimens, for instance, deviate slightly from the
type
in having a frontal shield with a more pronounced reticulate pattern of fine ridges, while in the
type
the surface is only faintly rugose, whereas all other characters coincide. Genetic studies will certainly be needed to distinguish intra- from interspecific variability.
Schizomavella fischeri
is, at present, considered to occur along the western Iberian shelf and slope to the central Mediterranean Sea at depths of
250–1100 m
. At Galicia Bank the species was found at 13 stations between 685 and
1414 m
.
TABLE 21.
Measurements (in mm) of
Schizomavella fischeri
.
Mean |
SD |
Minimum |
Maximum |
N |
Autozooid length |
0.714 |
0.0728 |
0.574 |
0.869 |
20 |
Autozooid width |
0.634 |
0.1179 |
0.500 |
0.910 |
20 |
Orifice length |
0.133 |
0.0093 |
0.114 |
0.152 |
22 |
Orifice width |
0.143 |
0.0081 |
0.126 |
0.161 |
22 |
Ooecium length |
0.281 |
0.0257 |
0.240 |
0.309 |
12 |
Ooecium width |
0.306 |
0.0109 |
0.289 |
0.327 |
12 |
Avicularium length |
0.065 |
0.0107 |
0.045 |
0.080 |
15 |
Avicularium width |
0.041 |
0.0043 |
0.031 |
0.048 |
15 |
SD, standard deviation; N, number of measurements