New species of Bairdioidea (Crustacea, Ostracoda) from the Southern Ocean and discussions on Bairdoppilata simplex (Brady, 1880),? Bairdoppilata labiata (Müller, 1908) and Bythopussella aculeata (Müller, 1908) *
Author
Brandão, Simone N.
text
Zootaxa
2008
1866
373
452
journal article
10.5281/zenodo.183820
287b1420-5c7c-4a05-ae95-e4c9121b51a6
11755326
183820
Bythocypris richarddinglei
sp. nov.
(
Figs. 18
,
37
,
38
)
Etymology.
In honour of Dr. Richard V. Dingle for his important contribution to the knowledge of deepsea fossil and recent Ostracoda, especially from the southeastern Atlantic.
Material
: 5 live specimens.
Holotype
: 1 A F (SNB 0253), ANDEEP III, # 16–11,
ZMH
K
41289.
Paratypes
:
1 A F (SNB 0095), ANDEEP III, # 16–11,
ZMH
K
41290; 1 A F (SNB 0093), ANDEEP III, # 16–7,
ZMH
K
41291; 1 A F (SNB 0250), 1 (A1) (SNB 0252), ANDEEP III, # 16–10–S,
ZMH
K
41292.
Distribution.
Cape Basin, Southeastern Atlantic,
4686 to 4723m
.
Measurements (
Fig. 18
)
.
Holotype
, LV–L
1.27mm
, H
0.73mm
; RV–L
1.26mm
, H
0.64mm
.
Paratypes
, LV–A F L
1.21–1.26mm
, H
0.70–0.72mm
; (A1) L
1.02mm
, H
0.60mm
.
Diagnosis.
LV outline subrectangular, with smoothly arched dorsal margin, maximum height posterior to midlength. RV subtrapezoidal with fairly straight anterodorsal margin and highly arched posterodorsal margin. LV and RV with slightly concave ventral margin and obtuse posterior angle. Podomere VI of AII wider than long, with 1 long and 1 mediumsized claws, 2 mediumsized setae and 1 tiny seta. MxI with 7 strahlen and 24 or 25 feathered setae. Vibratory plate of ApV with 4 or 5 strahlen and 10 setae. Fu with 2 short, 1 mediumsized and 2 long feathered setae. Genital lobe suboval with tubular internal process.
FIGURE 37.
Bythocypris richarddinglei
sp. nov.
Legend:
A–F
, holotype, A F (ZMH K41289, SNB 0253).
A
, RV ev,
B
, LV ev,
C
, AI,
D
, AII,
E
, Md,
F
, MxI. Scale bars:
A–B
, 500µm;
C–F
, 100 µm.
FIGURE 38.
Bythocypris richarddinglei
sp. nov.
Legend:
A–C, E, G
, holotype, A F (ZMH K41289, SNB 0253);
D, F, H
, paratype, A F (ZMH K41290, SNB 0095);
I
, paratype, A F (ZMH K41292, SNB 0250).
A–B
, ApV;
C
, ApVI;
D–E,
Fu;
F–I
, genital lobe. Scale bars: 100µm.
Description.
LV outline subrectangular; with smoothly arched dorsal margin; steep posterodorsal margin; broadly rounded anterior margin; slightly concave ventral margin; maximum height posterior to midlength. RV subtrapezoidal; with fairly straight anterodorsal margin; sinuate posterodorsal margin; truncate anterior margin; concave ventral margin; maximum height at midlength. LV and RV with obtuse posterior angle. Maximum length inferior to midheight. Calcified inner lamella fairly narrow; zone of concrescence very narrow, with numerous straight marginal pore canals. Adductor muscle scars bythocypridid, occupying less than 1/3 of valve height.
AI very robust; with relatively short and very strongly sclerotized setae; podomeres II and III fused; chaetotaxy 1(0/0), 2(0/.1)+3(0/.2), 4(1/0), 5(.2/.3), 6(.2/.3), 7(0/0:5). AII stout; with short podomeres III, IV and VI; exopodite with 2 long and 1 tiny setae; podomere VI wider than long, with 1 long and 1 mediumsized claws, 1 tiny seta, and 2 mediumsized setae; chaetotaxy 1(0/0:
2i
), 2(.1/0:
1i
), 3(0/.2.1.1), 4(0/.2r.2), 5(.1.1c./.1.1), 6(0/0:1r,1c,2,1c). Md with 3 feathered setae on the exopodite; masticatory process with 1 or 2 bifurcate and 3 or 4 trifurcate teeth and several short setae; chaetotaxy of palp 1(.1/.1:
1i
), 2(.1./.1:
1i
), 3(.5./.1:2
3
i), 4(.2./0:34). MxI with 7 strahlen and 24 or 25 feathered setae; ventral endite with 2 ventral setae and several broad, feathered, distal claws; other endites with 1 ventral seta each plus several simple distal setae; all setae of palp not feathered; palp chaetotaxy (.1.1.1./.2.:1c). Vibratory plate of ApV with 4 or 5 long strahlen and 10 mediumsized setae; podomeres of ApV to ApVII robust, with long and feathered terminal claws; exopodite of ApVI and VII without or with 1 tiny seta; chaetotaxy of ApVVII ApV1(.1.1.02/0:
1i
,1), ApVIVII 1(.1.1.1/0:
1i
), ApVVII2(.2/0), 3(.1/0), 4(.1/0), (0/0:2,1c). Fu with 2 short, 1 mediumsized, and 2 long feathered setae; one tiny seta between Fu rods. Genital lobe suboval with tubular internal process.
Remarks.
The valves of
Bythocypris richarddinglei
sp. nov.
differ from
Bythocypris reniformis
Brady, 1880
sensu
Puri and Hulings
(1976: Pl. 2.7–10,
Fig. 1
) and
B. praerenis
sp. nov.
by the more rounded outline, greater height in relation to length, and larger size (LV L:
1.21 to 1.27mm
, instead of
1.09mm
) of the former species. The valves of
Bythocypris
[sic]
reniformis
recorded by
Maddocks (1969,
Fig. 45
.J–M)
from the southwestern Atlantic (
Albatross
, #2763,
24°17’S
,
42°48’30’’W
,
1227m
) are larger (LV L:
1.52–1.61mm
), and more subtriangular than those of the new species described herein, with the maximum height of LV and RV at midlength, instead of posterior to it.
Bythocypris
[sic]
reniformis
recorded by
Maddocks (1969,
Fig. 45
.N–U)
from the
Mozambique
Channel, Southwestern Indian Ocean (R. V.
Anton Bruun
, cruises 7 and 8, #365D,
23°20’S
, 43°33E, 695
475m
) present more similar, rectilinear outline to
B. richarddinglei
sp. nov.
, but a more arcuate LV dorsal margin, and more rounded RV dorsal margin.
B. eltanina
Maddocks, 1969
,
B. spiriscutica
Maddocks, 1969
,
B. promoza
Maddocks, 1973
,
Bythocypris mozambiquensis
Maddocks, 1969
, and
B. polarsterni
sp. nov.
are more subtriangular than
Bythocypris richarddinglei
sp. nov.
Bythocypris elongata
Brady, 1880
,
Bythocypris prolata
Maddocks, 1969
are more elongated than
B. richarddinglei
sp. nov.
Bythocypris affins affins
Brady, 1886 (
sensu
Brady & Norman 1889
: 242)
is smaller and more elongate, with a more smoothly rounded posterior angle.
Bythocypris affins madagascarensis
Maddocks, 1969
is higher in relation to length and with the maximum height of LV at midlength instead of conspicuously posterior to it.