Taxonomic applications of the esophageal flapper valve in the Genus Neonesidea (Bairdioidea, Podocopida, Ostracoda), including descriptions of new and poorly known species from the Caribbean and Gulf of Mexico
Author
Maddocks, Rosalie F.
text
Zootaxa
2021
2021-01-11
4903
4
451
492
journal article
8977
10.11646/zootaxa.4903.4.1
ec5ab0d0-05d0-493b-9359-2fbe1265656f
1175-5326
4431228
D8AA9035-EB27-4F50-9246-B5450D71F3E2
Neonesidea longisetosa
(
Brady, 1902
)
(
Figure 11
-I–P, 12A–S; Graph 4)
1902
Bairdia longisetosa
sp. nov.
: Brady: 197, Pl. 25, figs. 8–9.
1966
Bairdia longisetosa
Brady—Bold
, p. 45, Pl. 2, figs. 7a–b.
1968
Bairdia longisetosa
Brady—Bold
, p. 48, Pl. 2, figs. 3a–b.
partim 1969
Neonesidea gerda
(Benson & Coleman), 1964
—Maddocks, p. 24,
Figs. 7
A–K.
1975
Bairdia longisetosa
Brady—Bold
pp. 585, 586, 589, 590, 593.
1975
Neonesidea longisetosa
(Brady), 1902
—Teeter, p. 417,
Figs. 3a
,
4a
.
1978
Bairdia longisetosa
Brady—Bold
, Table 9.
1982
Neonesidea longisetosa
(Brady)
—Breman, Pl. 3, fig. E.
non 1982
Neonesidea longisetosa
(Brady)
—Krutak, Pl. 5, figs. 1–5 [=
N. gerda
].
? 1983
Neonesidea longisetosa
(Brady)
—Palacios-Fest
et al
., Pl. 1, fig. 16 (only, not fig. 17).
1988
Bairdia longisetosa
Brady—Bold
, p. 22.
non 1990
Bairdia
cf.
B. longisetosa
Brady—Machain-Castillo Table 2, p. 122 [=
N. gerda
].
? 1992
Bairdia longisetosa
Brady—Machain-Castillo & Gío-Argáez (1992), Appendix I, p. 22 [part, may include
N. gerda
]
partim 1993
Neonesidea longisetosa
(Brady)
—Machain Castillo & Gío-Argáez, p. 258 [part, also includes
N. gerda
].
1994
Neonesidea longisetosa
(
Brady, 1902
)
—Krutak & Gío-Argáez, p. 200, Pl. 2, figs. 1–6.
1999
Neonesidea longisetosa
(
Brady, 1902
)
—Coimbra
et al
., Pl. 3, fig. 4.
non 2000
Neonesidea longisetosa
(
Brady 1902
)
—Keyser & Scĥning, Pl. 2, fig. 19 [=
N. omnivaga
]
2002
Neonesidea longisetosa
(
Brady, 1902
)
—Coimbra & Carreño, p. 193, Pl. 2, figs. 21–22.
partim 2009
Neonesidea longisetosa
(Brady)
—Maddocks
et al
., p. 888 [part, also includes
N. gerda
].
non 2014a
Neonesidea longisetosa
(
Brady, 1902
)
—Meireles
et al
., p. 16, Pl. 1, fig. a; Pl. 2, figs. a–l [= a species of the
N. tenera
species-group].
non 2014b
Neonesidea longisetosa
(
Brady, 1902
)
—Meireles
et al
.,
Figs. 2–9
.
Material:
Three dry male carapaces with fragmentary soft parts from
Belize
; one fragmentary living male from
the Bahamas
; numerous empty carapaces and valves from shallow-water carbonate sediments of
the Bahamas
,
Belize
,
Cuba
, the Florida Keys, Grand Cayman Island,
Jamaica
, and the
U.S. Virgin Islands
.
FIGURE 11
.
Neonesidea gerda
(Benson and Coleman)
; A–D, specimen
2397F
, from SW Florida; E–G,
4041W
; H, specimen
4043W
; both from Florida Keys.
Neonesidea longisetosa
(Brady)
; I, specimen
4046W
; J–P, specimen
4045M
; both from Belize. A–B, fragmentary RV and LV exteriors in TL; C, posteroventral flange and sensilla of RV; D, posteroventral marginal denticles and sensilla of LV, but no terminal spine is visible; E–F, RV exterior in TL; G, interior of RV in RL, with fragments of dry appendages and two food balls (f) in domicilium; H–I, DV in RL; J–K, interiors of LV and RV in RL, with fragments of appendages (brown) and two food balls (f); L–M, RV and LV exteriors in TL with fragments of appendages (brown) and two food balls (f); N, posteroventral fringe and terminal spine of RV in TL, with dry food ball (f), hemipenis (h), plate of EV (p), and limb fragments; O, posteroventral region of LV, with marginal denticles, opaque spot, and food ball (f), but no terminal spine is visible; P, interior of posterior region of RV in TL, after removing food ball, showing terminal spine, hemipenis (h), and a limb fragment. Scale bar = 50 µm.
FIGURE 12
.
Neonesidea longisetosa
(Brady)
. A–O, subfossil specimen
4045M
from Belize; P–Q, specimen
1652M
from the Bahamas; S, subfossil specimen
4053W
from Jamaica. A. A–D, hemipenis, with distal details; E, corner tooth of plate; F–G, VV of plate at high and low focus; H, interior of posteroventral region of RV, showing dry fragments of plate and ring; I–L, diagonal view of plate standing upright within RV interior, from high focus to low focus; M–N, edge view of posterior margin of same plate after removal from valve, showing pyramidal teeth and row of ventral setules, the dorsal surface is up (concave); P–R, hemipenis, with distal details; S, VV of EV with ring and plate. Scale bar = 50 µm.
Dimensions:
Specimen 4045M, LVL
1.061 mm
, LVH
0.614 mm
. Brady reported L
1.1 mm
. See also Graph 4.
Supplemental Description:
Most of the characteristics described by Brady are typical for most species of the
N. schulzi
species-group, including the subtly subrhomboidal but streamlined carapace with equant valves, obliquely subtruncate anteroventral margin, caudate posterior angle, and conspicuous carapace sensilla. The lateral outline is elongate-ovate, with smoothly arched dorsal margin, indistinct posterodorsal angle, caudate posterior end, tripartite ventral margin with upswung anteroventral and posteroventral segments, and rounded anterior margin. The acute, caudate posterior angle of the LV is located at approximately 33% of height. Well-conserved specimens have a tiny terminal spine at the caudal angle of each valve, conspicuous anteromarginal and posteromarginal denticles on the LV, and narrow anteromarginal and posteromarginal frills on the RV. The patch pattern consists of a large central oval spot, small spots in the anterior and posterior angles, and less distinct spots or streaks at the anterodorsal and posterodorsal angles. The dorsal spots are most easily seen in dorsal views of a whole carapace.
The hemipenis of
N. longisetosa
has a moderately long, arcuate copulatory tube, which arises near the base of the median segment. Distally, the tube is contained within a hollow, obliquely-curved, well-sclerotized, claw-like projection. At its end the copulatory tube splits into two or three threads. The terminal segment of the hemipenis is a hood-like plate, the inner surface of which is densely corrugated with wavy chitin threads, which rise above the surface as setules or tiny thorns. At the base of this segment is a well-sclerotized, obliquely-wrinkled ridge with one sharp tooth, the end of which articulates against the base of the clawlike projection.
The esophageal plate is a rather broadly flaring triangle. The curved posterior edge has a large, sharply triangular to subpyramidal tooth on either side of the medial gap, followed by about four smaller teeth of equal or diminishing sizes, subconical to subpyramidal in shape, and a prominent cluster of multilobate teeth at the corner. The U- to V-shaped ventral bracket has long diagonal horns directed outward and down, triangular lateral walls, and a row of tubercles along the anterior edge.
Remarks:
N. longisetosa
is significantly larger than
N. gerda
but has similar carapace proportions. The lateral outline usually has a more up-curved posterior angle and more conspicuous marginal denticles on the LV. In dorsal view, as compared to
N. gerda
, it has more curved contours with more rounded anterior and posterior ends. In fresh specimens the central opaque spot of the patch pattern is larger than that of
N. gerda
and approximately oval rather than oblong. The single posterodorsal opaque spot easily distinguishes
N. longisetosa
from
N. gerda
, which has no spot at this location. This mark is also convenient for quickly separating adult and juvenile valves of
N. longisetosa
from
Bairdoppilata cushmani
(
Tressler, 1949
)
, which consistently has two opaque spots at this posterodorsal location, and which occurs abundantly in the same subfossil assemblages.
The setulose, quarter-spherical hood and asymmetrical serrate ridge of the distal segment of the hemipenis of
N. longisetosa
are easily distinguished from the smooth, half-cylindrical lamellae and aesthetasc of
N. gerda
.
The three specimens illustrated as
N. gerda
by
Maddocks (1969
,
Figs. 7
A–K) from
Tortugas
(Florida Keys) and Bimini and Andros (Bahama Islands) all belong to
N. longisetosa
. Her drawing of the hemipenis (
Fig. 7D
) shows the setulose distal texture characteristic of that species. Her drawings of the valve exteriors (
Figs. 7
H–K) show the distinct posterodorsal opaque spot, which is characteristic of
N. longisetosa
. The measurements cited by
Maddocks (1969
, p. 24) for these three males are among the smallest known for the species.
The specimens illustrated as
N. longisetosa
by
Krutak (1982)
from reefs off Vera Cruz are smaller, more angular in outline, and more triangular in shape. It is likely that they are
N. gerda
.
The specimen illustrated as
N. longisetosa
from
Bermuda
by Keyser & Scĥning (2000) is
N. omnivaga
.
N. longisetosa
has not been seen in sediment samples from the
Bermuda
Platform.
N. longisetosa
resembles
N. caraionae
n. sp.
in carapace form and outline, but it is smaller. The hemipenis has a much shorter copulatory tube and a hood-like, textured terminal segment, easily distinguished from the extraordinarily long tube and discoidal terminal segment of
N. caraionae
.
N. longisetosa
has sometimes been confused with
Neonesidea crosskeiana
(
Brady, 1866
)
, which lives in the eastern Mediterranean; see
Titterton
et al
. (2001)
for redescription and clarification of that species.
The population from the Azores, which was misidentified as
N. longisetosa
by
Meireles
et al
. (2014a
,
2014b
), represents a species of the
N. tenera
species-group (informal). Their illustrations of the ovate lateral outline show a nearly symmetrical, high-arched dorsum and a much less caudate posterior end. It shows similarities to Mediterranean species, such as
N. decipiens
or
N. mediterranea
, well as to the West African species, “
Paranesidea
” multiforma
Witte, 1993
.
Meireles
et al
. (2014a
, p. 16) attempted to synonymize
N. gerda
and
N. omnivaga
with
N. longisetosa
, but their justification was vague (“The collected specimens are identical to
N. longisetosa
, considering the carapace morphology. The morphology of the soft parts is comparable to the figures that
Maddocks (1969)
gave for
Neonesidea gerda
….”
). Although they recovered hundreds of living and subfossil specimens, Meireles
et al
. did not provide carapace dimensions, did not describe or illustrate soft parts, and did not say whether they examined actual specimens from
Bermuda
and Caribbean localities. The species living in the Azores is certainly not conspecific with the material examined here for
N. caraionae
,
N. gerda
,
N. longisetosa
, and
N. omnivaga
. Indeed, the wave-dominated rocky slopes of the Azores, washed by the cold Canaries Current (14
oC
), are unlikely to share species in common with the carbonate platform assemblages of the tropical Caribbean and
Bermuda
.
Distribution:
N. longisetosa
was originally described by Brady from St. Thomas,
U.S. Virgin Islands
. In the samples examined for this study, it is abundant in shallow-water carbonate sands of
Belize
,
Jamaica
and Grand Cayman Island; and it is less common or rare in samples from
the Bahamas
, the Florida Keys, and Hopetown Harbour,
U.S. Virgin Islands
. It is not represented in collections from
Bermuda
.
GRAPH 5
. H/L scatter plot for LV and RV of
N. gerda
from four geographic localities: Florida Keys, Stetson Bank,
Guantanamo
Bay (
Cuba
), and an OGMEX sample from the Bay of Campeche, southern Gulf of Mexico. As usual, LV are slightly higher than RV but about the same length. Known females plot in the upper right of the adult cluster, and known males plot in the lower left.
GRAPH 6
. H/L scatter plot for LV (only) of
N. caraionae
and
N. longisetosa
. The specimens of
N. longisetosa
were collected from five localities:
Belize
, the Florida Keys, the Bahama Islands,
Guantanamo
Bay (
Cuba
), and the
U.S. Virgin Islands
. As usual, known females plot in the upper right of the adult cluster, and known males plot in the lower left. The two male specimens of
N. caraionae
(open circles) are slightly longer than females of
N. longisetosa
, though about the same height.
N. longisetosa
has been reported from Alacran Reef on the northwestern
Yucatan
platform, northeastern
Yucatan
, and the Caribbean coast of
Mexico
;
Belize
; Buccoo Reef,
Tobago
;
Nicaragua
;
Colon
Harbour,
Panama
; the Gulf of
Venezuela
; the Brazilian equatorial shelf; and the Neogene of
Jamaica
and
the Dominican
Republic (
Breman 1982
;
Bold 1966
,
1968
,
1989
;
Teeter 1975
;
Palacios-Fest
et al
. 1983
,
Krutak & Gío-Argáez 1994
,
Coimbra & Carreño 2002
). On Alacran Reef it was said to be consistently restricted to a particular facies: “Shallow, agitated environment, e.g., windward reef flat, shallow patchreefs, leeward sandflats” (
Bold 1989
, p. 145, Table 1). In northeastern
Yucatan
it was described as abundant in modern carbonate grainstones, but less common in lagoonal sediments (
Krutak & Gío-Argáez 1994
). Reported occurrences on the western platform of
Yucatan
and at localities in the central and southern Caribbean are plausible but cannot be verified without illustrations and dimensions (
Machain-Castillo & Gío-Argáez 1992
Appendix I;
Bold 1977
, Table 3; 1988, p. 22). The identifications under this name from the Veracruz-Anton Lizardo reefs by
Krutak (1982)
apply to
N. gerda
. Reported occurrences in the Bay of
Campeche
(
Machain-Castillo 1990
) probably apply to
N. gerda
. In the checklist by
Maddocks
et al
. (2009
, p. 888), the distribution of this species should be restricted to exclude occurrences in the northwestern and southwestern Gulf of
Mexico
, which apply to
N. gerda
.
Fossil specimens have been reported from the Upper Miocene to Recent of
Venezuela
,
Panama
,
the Dominican
Republic,
Jamaica
, and other Caribbean localities (
Bold, 1966
,
1968
,
1975
,
1978
,
1988
).