Ostracods (Crustacea) associated with microbialites across the Permian-Triassic boundary in Dajiang (Guizhou Province, South China)
Author
Forel, Marie-Béatrice
text
European Journal of Taxonomy
2012
2012-08-01
19
1
34
journal article
21834
10.5852/ejt.2012.19
9a19c75e-a62b-4143-adda-28789a95da5c
2118-9773
3857896
893DB151-7B86-485C-932F-A01C57B20316
Bairdia jeromei
sp. nov.
Fig. 4
G-P
Diagnosis
Massive and subrectangular species of
Bairdia
, with DB and VB subparallel, long DB (~ 60% of Lmax), rhombic dorsal view.
Etymology
Personal dedication to Jérôme Cougoul.
Material examined
Holotype
One carapace (
Fig. 4G
), sample 05PAJ43, collection number
P6M2945
.
Paratype
One carapace (
Fig. 4J
), sample 05PAJ43, collection number P6M2948.
Other material
10 carapaces, several fragments. The species is known from its
type
locality only.
Type locality
Wujiaping and Daye Formations (samples 05PAJ23, 25, 26, 28, 32, 42, 43), Dajiang section (
25°33’56’’N-
106°39’41’’E
),
Guizhou Province
, South
China
, Changhsingian and Griesbachian, Late Permian and Early Triassic.
Measurements (
Fig. 6
)
L = 722 – 1024 μm; H = 410 – 597 μm; H/L = 0.56 – 0.64.
Description
Carapace massive, elongated and subrectangular in lateral view; surface smooth; LV larger than RV, overlapping at dorsum and VB; bairdian beaks at AB and PB poorly expressed; PDB, DB and ADB distinct at both valves; PDB steeply bent backward, long (~ 65% of Hmax) and slightly convex; DB long (~60% of Lmax) and gently convex; ADB slightly concave at RV, shorter than PDB; ventral part rounded; VB long, convex at LV, concave at RV; AVB and PVB rounded, AVB longer than PVB; carapace slightly postplete to amplete; Lmax below mid-H; dorsal view rhombic with LV’s Wmax in posterior 1/3 of Lmax, in anterior 1/3 at RV.
Fig. 6.
Height/length diagram of
Bairdia jeromei
sp. nov.
Remarks
In lateral view,
Bairdia jeromei
sp. nov.
is similar to
Orthobairdia
sp.1
sensu
Crasquin
et al.
, 2010
from the Permian of the Meishan section,
Zhejiang Province
, South
China
(
Crasquin
et al.
2010
) but here the dorsal view clearly precludes the generic attribution to
Orthobairdia
.