Revision of the genus Crepis Jullien (Bryozoa: Cheilostomata) with description of a new genus and family and notes on Chlidoniidae
Author
Reverter-Gil, Oscar
Author
Souto, Javier
Author
Fernández-Pulpeiro, Eugenio
text
Zootaxa
2011
2993
1
22
journal article
10.5281/zenodo.203919
2af3e798-9a86-4a06-b094-009841e06894
1175-5326
203919
Crepis harmelini
n. sp.
(
Figs 5–11
;
Tables 2
,
3
)
Crepis longipes
:
Harmelin & d’Hondt 1992
: 39
, pl. 3, figs C, D.
Material examined.
Holotype
:
MNHN
IB-
2009-1473,
Balgim
Stn DR152,
35º56.7’ N
,
05º34.7’ W
,
550 m
.
Paratype
# 1:
MNHN
IB-
2009-1474,
Balgim
Stn DR153,
35º55.8’ N
,
05º35.3’ W
,
580 m
, one ovicelled zooid.
Paratype
# 2:
MNHN
IB-
2009-1475, E. Atlantic Ocean, M.O.
Noroit-Campagne Seamount 1
, Stn CP79,
33º49.0’ N
,
14º22.6’ W
,
242–260 m
,
10/10/1987
, Banc Seine, collected by J.-G. Harmelin, one colony with ovicells.
Etymology.
Named after our appreciated colleague and collector of the specimens, Jean-Georges Harmelin.
Description.
Colony adnate, delicate, composed of branching uniserial series. Autozooids comprising a pyriform dilatation and slender cauda of variable length; lateral walls vertical, especially in distal half of dilatation, with smooth exterior-walled (gymnocystal) calcification; 2–4 pairs of short basal lobes fixing the zooid to the substratum. Gymnocyst mostly reduced to the proximal cauda. Dilatation with extensive area of membranous frontal wall attached to granular oval rim that is higher distally. Underlying cryptocyst flat, granular, merging into marginal rim at its proximal end where the rim is barely evident. Opesia semi-oval, occupying about one third of frontal area, its proximal margin straight, slightly concave, or occasionally convex in the centre; lateral borders projecting inwards at level of operculum which occupies two thirds of opesia.
Zooidal branching frequent; autozooid giving rise to two lateral buds from the distal half of dilatation; caudae of daughter zooids at right angles to parent zooid. Ovicell independent, prominent, quite large, not closed by operculum, recumbent upon and concealing part of the cauda; ectooecium mostly membranous, a proximal band calcified, smooth, forming the rim that overarches the orifice, continuous laterally with concealed cauda of distal zooid, flanked by two series of longitudinal fine creases; endooecium uniformly granular. Spines and heterozooids absent. Ancestrula unknown.
Remarks.
Harmelin & d’Hondt (1992)
reported
C. longipes
based on material collected from three stations in the Strait of
Gibraltar
area, at
362–580 m
depth. We have been able to examine two samples of this material sent by Dr J.-G. Harmelin — one colony from station DR152 and an ovicelled zooid from station DR153. The rest of the material reported in their paper seems to have been lost. We also examined a colony collected
242–260 m
depth from a seamount northeast of Madeira, sent by Dr Harmelin (
Figs 8–11
).
This material exhibits a series of important differences compared to
C
.
longipes
as described herein: autozooids of
C. harmelini
n. sp.
are smaller and more pyriform and the lateral walls are more vertical and more projected frontally in the distal part of the autozooid; in
C. longipes
the zooids are regularly oval and larger, with sloping lateral walls.
Crepis harmelini
has several basal lobes abutting upon the substratum that do not occur in
C. longipes
.
The opesia is also smaller and shows a slight constriction at the level of the hinge of the operculum; the cauda is wider and its diameter is not constant as in
C. longipes
, but it gradually increases distally so that the limit between the cauda and the distal portion of the zooid is poorly defined. The branches in
C. harmelini
are usually placed in a more distal position. According to the description by
Harmelin & d’Hondt (1992)
, although the species is creeping, the cauda can cross gaps in the substratum, a feature not seen in the material of
C. longipes
. Finally,
C. harmelini
is the only species in the genus in which ovicells have so far been seen, previously described by
Harmelin & d’Hondt (1992
, as
C. longipes
).
FIGURES 5–11.
Crepis harmelini
n. sp.
5
, several autozooids (MNHN IB-2009-1473, holotype);
6
, same, detail of an autozooid);
7
, ovicelled zooid (MNHN IB-2009-1474, paratype);
8
, view of a colony (MNHN IB-2009-1475, paratype);
9
, same, detail of an autozooid;
10
, same, ovicelled zooid;
11
, same, ovicelled zooid joined to the distal autozooid.
The material collected from Madeira differs from that from the Strait of
Gibraltar
by exhibiting shorter caudae; however, the distal dilatation is similar in both of them (see
Figs 6, 9
). Only one ovicell was observed in the material from the Strait of
Gibraltar
, whereas that from Madeira presents several ovicells; all of them are also similar (see
Figs 7, 10
). Thus, we consider that the material from both localities belongs to the same species. A single ovicell of the material from Madeira so completely conceals the proximal end of the distal zooid that the granular endooecial surface is continuous with its cryptocyst (
Fig. 11
).
TABLE 2.
Measurements (in mm) of
Crepis harmelini
n. sp.
(MNHN IB-2009-1473, holotype)
Mean SD Minimum Maximum N Frontal surface length 0.410 0.0301 0.367 0.458 11 Frontal surface width 0.225 0.0166 0.193 0.247 11 Opesia length 0.124 0.0155 0.096 0.157 11 Opesia width 0.114 0.0126 0.090 0.133 11 Opesia L/Zooid L 30.3 % 26.2 % 34.2 %
Cauda length 0.851 0.1396 0.657 1.029 9 Cauda width 0.049 0.0084 0.036 0.061 15
SD, Standard deviation; N, number of measurements.
TABLE 3.
Measurements (in mm) of
Crepis harmelini
n. sp.
(MNHN IB-2009-1475, paratype)
Mean |
SD |
Minimum |
Maximum |
N |
Frontal surface length |
0.391 |
0.0187 |
0.354 |
0.433 |
19 |
Frontal surface width |
0.222 |
0.0105 |
0.205 |
0.239 |
19 |
Opesia length |
0.117 |
0.0090 |
0.101 |
0.134 |
19 |
Opesia width |
0.124 |
0.0089 |
0.105 |
0.142 |
19 |
Opesia L/Zooid L |
30.0 % |
28.5 % |
30.9 % |
Cauda length |
0.324 |
0.0606 |
0.183 |
0.452 |
20 |
Cauda width |
0.043 |
0.0049 |
0.031 |
0.053 |
20 |
Ovicell length |
0.146 |
0.0139 |
0.132 |
0.165 |
4 |
Ovicell width |
0.206 |
0.0114 |
0.198 |
0.223 |
4 |
SD, Standard deviation; N, number of measurements.