Recent Brachiopoda from the Mozambique-Madagascar area, western Indian Ocean
Author
Bitner, Maria Aleksandra
Institute of Paleobiology, Polish Academy of Sciences, ul. Twarda 51 / 55, 00 - 818 Warszaw (Poland) bitner @ twarda. pan. pl
bitner@twarda.pan.pl
Author
Logan, Alan
Centre for Coastal Studies, University of New Brunswick, Saint John, N. B., E 2 L 4 L 5 (Canada) logan @ unbsj. ca Published on 25 March 2016
logan@unbsj.ca
text
Zoosystema
2016
2016-03-31
38
1
5
41
http://dx.doi.org/10.5252/z2016n1a1
journal article
10.5252/z2016n1a1
1638-9387
4578148
urn:lsid:zoobank.org:pub:96BFE594-1B39-4541-9441-181617BD4CF9
Macandrevia emigi
n. sp.
(
Fig. 12
;
Table 11
)
TYPE MATERIAL
. —
Mozambique
Channel
. MAINBAZA, stn
CC 3170
,
holotype
(
MNHN
IB-2013-71
;
Fig. 12
J-Q). — Same data, stn CP 3139, three
paratypes
(
MNHN
IB-2013-72
-
74
;
Fig. 12
D-I)
.
TYPE
LOCALITY
. —
Mozambique
Channel,
Maputo
transect,
MAIN- BAZA
, stn
CC
3170,
25°58’S
,
34°47’E
,
949-
952 m
.
ETYMOLOGY. — Named in honour of Christian C. Emig (BrachNet, Marseille,
France
), a prodigious worker in the field of inarticulated brachiopods.
MATERIAL
EXAMINED. —
Mozambique
Channel
. MAINBAZA, stn CP 3139, 1 bivalved specimen. — Stn
CC
3170, 1 bivalved specimen.
South
Madagascar
.
ATIMO VATAE
, stn CP 3589, 35 bivalved immature specimens.
DESCRIPTION
Shell of medium size (maximum observed length 12.6 mm), thin, translucent, elongate oval to rounded while young to subpentagonal in adult, ventribiconvex. Shell surface smooth with numerous growth lines. Lateral commissures straight, anterior commissure rectimarginate to incipiently sulcate. Hinge line short, slightly curved. Beak suberect to erect. Foramen large, oval, permesothyrid, deltidial plates rudimentary. Ventral valve interior with small teeth supported by divergent dental plates united by a callus closely applied to the valve floor (
Fig. 12H, N
). Dorsal valve interior with small cardinal process and high inner socket ridges. Inner hinge plates attached directly to the valve floor. Low, short median septum present in early stages of ontogeny (
Fig. 12
D-F), in adults median septum absent (
Fig. 12O, P
). Loop long with narrow descending and ascending branches, transverse band moderately broad with short projections, and short spines anteriorly (
Fig. 12Q
).
REMARKS
The superfamily
Zeillerioidea
comprises 10 extant species belonging to a single genus,
Macandrevia
(
Logan 2007
)
. Species of the genus have previously been recorded virtually from pole to pole and usually from cold deep waters (
Cooper 1975
) but not from the Indian
Ocean
or western and central Pacific. This description of a new species, based mainly on
35 specimens
from South
Madagascar
, is thus the first record of the genus from the Indian
Ocean
. Most species of
Macandrevia
are eurybathic, with
M. tenera
extending down to
4600 m
but the depth range of
M. emigi
n. sp.
is much less. The new species is comparable in size to the northern Atlantic species,
M. novangliae
Cooper, 1977
and
M. tenera
(Jeffreys, 1876)
(
Cooper 1975
,
1977
,
1981b
), other species are much larger. However, the species from the
Madagascar
region differs from all hitherto described species in its triangular outline.