On a new marine podocopid genus and species (Ostracoda: Hemicytheridae) from Brazil
Author
Coimbra, João Carlos
Author
De Morais, Anderson L. M.
text
Zootaxa
2016
4193
1
167
176
journal article
37826
10.11646/zootaxa.4193.1.8
7d6ba2f2-5132-4f2b-a8fe-dc07c28ba1ce
1175-5326
166659
05CA72B0-2D74-44D5-B93C-DEA4155F18E9
Bulbocythere calida
sp. nov.
Fig. 3
: 1−18
1992
Echinocythereis
? sp.—Coimbra
et al
., p. 98–102, pl. 2, fig. 12, tabs. 1–4.
2008 Gen. et sp. indet.—Machado, p. 184–186, pl. 8, figs. 12–14, tabs. 4, 6 and 9.
Type
series.
Holotype
: MP-O-1396, adult female, LV.
Paratypes
: MP-O-2584, juvenile female, C; MP-O-2585, juvenile male, C; MP-O-2586, juvenile female; MP-O-2587, juvenile male, C; MP-O-2588, adult male, RV.
Type
locality.
Tamandaré Bay
(
8°45’S
,
35°06’W
),
Pernambuco
State, Northeastern
Brazil
.
Etymology.
Latin origin,
calidus
= warm, because of its distribution being restricted to warm waters.
Material.
33 carapaces and 17 valves, of which only two well-preserved valves and one eroded carapace are from adults.
Dimensions.
See table 2.
Description.
Carapace medium sized, thick-shelled and subrectangular in lateral view. Posterior cardinal angle conspicuous, mainly in LV. Maximum height anteriorly. In dorsal view, inflated-ovate. Maximum width just behind mid-length. Anterior margin rounded, with an antero-dorsal flange in LV. Posterior margin dorsally concave and convex ventrally, forming a gentle caudal process, more developed in RV. Few small blunt spines bordering both, the anterior and postero-ventral margins. Dorsal and ventral margins nearly straight and slightly converging towards the posterior end. Antero-median concavity hidden by swelling of the valves. Surface ornamented by numerous blunt tubercles with different sizes and forms, mostly of them aligned in poorly defined rows. Anteriorly, two rows run parallel to the margin converging to the prominent eye tubercle. A quite short tuberculate or undivided rib, larger in RV, extends behind the eye tubercle. Posteriorly, two almost inconspicuous short rows extend subparallel to the margin. Two anterior and three to four posterior rows radiating from the weakly developed subcentral tubercle. The tuberculate ornamentation shows a relatively high degree of variability, either between the sexes or between valves of the same sex. Normal pore canals quite numerous, scattered, very likely provided with a less conspicuous sieve structure hidden in the depth of the pore. Internally, hinge holamphidont. RV hinge has a well-developed anterior tooth and a deep post-adjacent socket with a median smooth groove ending in a bilobate subrectangular posterior tooth. Adductor muscle pattern an oblique row of four scars, the middle two subdivided. Frontal scar split in two scars, the upper one more rounded. Inner lamella moderately well developed. Line of concrescence and inner margin slightly separated anteriorly, leaving a narrow vestibule. Radial pore canals straight, simple and numerous. Sexual dimorphism pronounced. Males more elongate and slightly narrower than the females and with a relatively weakly developed ornamentation.
TABLE 1
. Occurrence of
Bulbocythere calida
gen. nov.
et sp. nov.
in the study area. Abbreviations and symbols: TQS—terrigenous quartzose sand; BS—biodetritical sand; TMS—terrigenous muddy sand; TS+CG—terrigenous sand with carbonate sand; TCS—terrigenous coarse sand; * adult; + juvenile. TAB-62 corresponds to the holotype.
Sample |
Latitude (S) |
Longitude (W) |
Depth (m) |
Sediments |
N° of valves and carapace |
TAB-62 |
08°45’ |
35°06’ |
7 |
BS |
3v (1*) |
L7-3759 |
08°03,5’ |
34°36’ |
50 |
BS |
1c (+) |
L7-3761 |
08°23’ |
34°41’ |
43 |
BS |
2v, 3c (+) |
L7-3763 |
08°32’ |
34°56’ |
25 |
BS |
1c (+) |
L7-3764 |
08°40’ |
35°00’ |
26 |
BS |
3c (+) |
L7-3767 |
09°19.5’ |
35°03’ |
44 |
BS |
4c (+) |
L7-3777 |
10°01’ |
35°54’ |
18 |
BS |
2c (+) |
L7-3778 |
10°12’ |
36°00’ |
22 |
BS |
1v, 3c (+) |
L7-3779 |
10°20’ |
36°04’ |
24 |
BS |
1v, 3c (+) |
L7-3786 |
11°17’ |
37°12’ |
22 |
TQS |
2v, 2c (+) |
L7-3787 |
11°25’ |
37°16’ |
15 |
TMS |
1v (+) |
L7-3788 |
11°38’ |
37°23’ |
18 |
TS+CG |
1v, 9c (1*) |
L7-3808 |
15°13’ |
38°54’ |
24 |
TS+CG |
1v (+) |
L7-3892 |
17°59’ |
38°01’ |
49 |
BS |
1v (+) |
L7-3906 |
18°26’ |
39°20’ |
24 |
TCS |
2v (1*) |
L7-3927 |
21°54’ |
40°11’ |
59 |
TMS |
1c (+) |
L7-3936 |
21°12.5’ |
40°35’ |
16 |
BS |
1v, 1c (+) |
FIGURE 3
.
Bulbocythere calida
gen. et sp. nov.
1–2 (MP-O-1396, female, holotype). 1—LV, 2—LV, internal view. 3–6 (MP- O-2584, female, paratype) 3—LV, 4—RV, 5—LV, internal view, 6—RV, internal view. 9–12 (MP-O-2585, male, paratype) 9— LV, 10—RV, 11—LV, internal view, 12—RV, internal view. 7–8 (MP-O-2584, female, paratype) 7—LV, central muscle scars, 8—RV, central muscle scars. 13–14 (MP-O-2585, male, paratype) 13—RV, central muscle scars, 14—LV, central muscle scars. 15 (MP-O-2586, female, paratype) carapace, dorsal view. 16 (MP-O-2587, male, paratype) carapace, dorsal view. 17 (MP-O- 2588, male, paratype) anterior and posterior marginal pore-canals, not to scale. Scale bars: 1–6, 9–12, 15–16 (100 µm); 7–8 (20 µm); 13–14 (50 µm).
TABLE 2
. Dimensions, sex and ontogenetic stage of the type-material of
Bulbocythere calida
gen. et sp. nov.
Material |
Sex/stage |
Length (mm) |
Height (mm) |
Width (mm) |
MP-O-2585 (opened c) |
Male/juvenile |
LV—0.79 RV—0.78 |
LV—0.37 RV—0.36 |
- |
MP-O-2587 (closed c) |
Male/juvenile |
LV—0.80 |
LV—0.39 |
0.40 |
MP-O-2588 (valve) |
Male/adult |
RV—0.85 |
RV—0.43 |
- |
MP-O-1396 (valve) |
Female/adult |
LV—0.78 |
LV—0.42 |
- |
MP-O-2584 (opened c) |
Female/juvenile |
LV—0.72 RV—0.71 |
LV—0.39 RV—0.36 |
- |
MP-O-2586 (closed c) |
Female/juvenile |
LV—0.69 |
LV—0.37 |
0.41 |
Remarks.
Bulbocythere calida
gen. et sp. nov.
is a peculiar hemicytherid. No similar species occurs in the Atlantic Ocean. Although we have analyzed more than one thousand samples, the larger female specimen (
holotype
) of this rare species is smaller (
0.78 mm
length) than we expected for a
Hemicytheridae
when compared with the adult male (
0.85 mm
length) of the same species. However, this is not so strange since other South Atlantic hemicytherid ostracods, such as
Ruggiericythere
Aiello, Coimbra & Barra, 2004
and some species of
Caudites
Coryell & Fields, 1973
(see
Coimbra & Ornellas 1987
) possess the same sex-size relationship.
Occurrence and distribution.
Bulbocythere calida
gen. et sp. nov.
was recorded only in 16 shallow-shelf samples and in the Tamandaré Bay. On the Brazilian shelf, this rare species occurs scattered along the Eastern and Northeastern warm regions, mainly on biodetritic bottoms (
Fig. 1
,
Tab. 1
). However, in the Tamandaré Bay it is relatively more abundant, as shown in
Table 1
of
Coimbra
et al.
(1992
, see
Echinocythereis
? sp.).