Ostracoda (Myodocopa) from Anchialine Caves and Ocean Blue Holes
Author
Kornicker, Louis S.
Author
Iliffe, Thomas M.
Author
Harrison-Nelson, Elizabeth
text
Zootaxa
2007
2007-08-31
1565
1
1
151
https://biotaxa.org/Zootaxa/article/view/zootaxa.1565.1.1
journal article
10.11646/zootaxa.1565.1.1
11755334
5095810
A2CDD9CB-CA5E-418B-A471-9EEFDC5CCF16
Pseudophilomedes ferulanus
Kornicker 1958
Figs. 46
,
47
Pseudophilomedes ferulana
Kornicker 1958: 235
, figs. 46: 1a,b, 2a,b: 56A–D.
Pseudophilomedes ferulanus
.—Kornicker 1989: 8.
Pseudophilomedes ferulana
.—
Darby 1965: 64–70
,
Fig. 10
, pls. 11,12.
Not
Pseudophilomedes ferulanus
.—
Kornicker 1967: 8
, figs. 1–6, pl. 1.—1969: 119, figs. 3, 4, pl. 11.—1977: 792.— 1984: 33, figs. 14–16.
Holotype
.
USNM 113287
, adult female on slides.
Type locality.
Bimini
,
Bahamas
, Great Bahama Bank.
Material.
Great Bahama Bank
,
Exuma
Cays
,
Great
Exuma
,
Stocking Island
(Bottomly’s Blue Hole),
Sta
99-065:
USNM 10214561
,
1 specimen
on slide and in alcohol
.
Distribution.
See
Kornicker (1984: 33)
. Herein, Great Bahama Bank, Stocking Island (Bottomly’s Blue Hole).
Description of instar II
(sex unknown) (
Figs. 46
,
47
). Carapace elongate with projecting caudal process (
Fig. 46
a,c,e
); incisure forming obtuse-angle (
Fig. 46
a,b,d
).
Ornamentation
(
Fig. 46
b–e
): Surface with widely distributed long and medium length bristles; long bristles with broad triangular basal part. Outer edge of rostrum with small nodes (
Fig. 46
b,d
). Ribs, punctations, and reticulations absent on USNM 1021461.
Infold:
Rostral infold broad with 4 long bristles forming row, and 1 minute bristle near ventral end of rostrum (
Fig. 46
d
). Infold of caudal process broad, with 2 indistinct bristles (
Fig. 46
e
). Narrow infold along anteroventral, ventral and posterior margins of valve. Anteroventral infold without bristles or parallel striations.
FIGURE 46.
Pseudophilomedes ferulanus
Kornicker 1958
, USNM 1021461, instar II, sex unknown:
a,
complete specimen from right side, length 0.69 mm;
b,
anterior of left valve, ov;
c,
posterior of left valve; ov;
d,
anterior left valve, iv;
e,
posterior left valve, iv;
f,
left first antenna drawn on body, lv;
g,
right second antenna, mv;
h,
left mandible, maxilla, and fifth limb drawn on body, lv;
i,
right mandible, mv;
j,
right maxilla, lv;
k,
left lamella of furca, lv;
l,
left lateral eye, protopod left second antenna, Bellonci Organ;
m,
Bellonci Organ and medial eye;
n,
posterior of body showing left Ysclerite, ventral end of girdle, and dorsal end of furca. Scale equals 0.05 mm (
b–n
).
FIGURE 47.
Pseudophilomedes ferulanus
Kornicker 1958
, USNM 1021461, instar II, sex unknown:
a,
left fifth limb, av;
b–e,
right fifth limb, pv;
f,
left sixth limb, lv;
g,
posterior of body showing Y-sclerite, girdle, and posterior end of furca. Scale equals 0.05 mm (
a,f,g)
and 0.02 mm (
b–e
).
Selvage:
Narrow fringed lamellar prolongation along anterior and ventral margins of valve. Prolongation not divided at incisure.
Central adductor muscle attachments:
Indistinct on USNM 10214561.
Carapace size
(length, height in mm): USNM 10214561, 0.69, 0.41.
First antenna
(
Fig. 46
f
): Segment 2 with 1 dorsal bristle. Segment 3 with 2 bristles (1 ventral, 1 dorsal). Segment 4 with 1 dorsal bristle. Long ventral bristle of segment 5 with small proximal filament. Segment 6 with small medial bristle near dorsal margin. Segment 7 with 3 bristles: a-bristle about 3 times length of bristle of 6th segment; b-bristle about twice length of a-bristle; c-bristle long, bare. Segment 8 with 4 long bare bristles.
Second antenna
(
Fig.
46
g
,l
): Protopodite bare; proximal connecting sclerite fairly linear. Endopod with 2 segments, each with 1 bristle. Exopod: Right limb of USNM 10214561 aberrant in having only 7 segments (
Fig.
46
g
); left limb with 9 segments; terminal segment of left limb with 2 bristle, of right limb with 3 bristles. Most bristles with natatory hairs, some also with slender proximal ventral spines; 1st segment with minute terminal medial spine-like bristle; some segments with distal spines forming row.
Mandible
(
Fig. 46
h,i
): Coxa endite bifurcate, spinous. Basis: dorsal margin with 1 distal and 2 terminal bristles; medial surface with 1 or 2 short bristles near ventral margin; ventral margin with 1 bristle near midlength. Exopod elongate with 2 terminal bristles. Endopod: 1st segment with 3 terminal ventral bristles; 2nd segment with 4 or 5 bristles on or near dorsal margin and 2 short distal bristles on ventral margin; 3rd segment with 3 slender bristles and 2 claw-like bristles.
Maxilla
(
Fig. 46
j
): Endite I with 2 terminal bristles and 2 terminal pectinate claws; endite II with 1 proximal bristle, 2 terminal bristles and 2 terminal claws; endite III with 1 long terminal bristle. Basis with 1 short dorsal terminal bristle and 1 long ventral terminal bristle. Exopod with 3 bristles (2 long, 1 short); base of exopod bristles on 1st endopod segment close to distal margin of basis. Endopod: 1st segment with distal dorsal bristle; 2nd segment with 3 short bristles and long terminal finger-like process with annulated narrower distal part.
Fifth limb
(
Fig. 47
a–e
): Epipod with 28 spinous bristles. Exopodite represented by 2 short bristles. Coxa with 2 endites: endite I with 2 short bristles; endite II with tooth with 3 prongs and 3 bristles. Basis with 2 endites: endite I anterior with tooth with 2 prongs (distal tooth with small marginal prong on inner edge); endite II posterior with 1 long posterior proximal bristle and long slender tooth; inner edge of tooth with 2 teeth (proxima1 with 3 prongs, distal single). Exopod represented by two bristles. Endopod: segment 1 represented by single bristle on posterior surface; segment 2 elongate with 4 bristles (1 short proximal, 3 terminal (stout terminal bristle with stout proximal marginal spines)).
Sixth limb
(
Fig. 47
f
): Bilobed with marginal spines and 1 long spinous bristle on smaller lobe.
Seventh limb:
Absent.
Furca
(
Fig. 46
k
): Each lamella with 5 claws decreasing in length and width posteriorly along lamella. A stout spine adjacent to base of posterior edge of claw 5; additional slender spines along lamella following claw 5. Anterior of right lamella with slender spines near base of claw 1. Claw 1 with stout medially tooth proximal to midlength. All claws with proximal teeth along posterior edge.
Bellonci Organ
(
Fig. 46
l,m
): Elongate with rounded tip bearing few spines, and sutures in proximal part.
Eyes:
Medial eye only weekly pigmented and small (
Fig.
46
m
). Lateral eye small, pigmented, and with 3 ommatidia (
Fig. 46
l
).
Y-Sclerite
(
Figs. 46
n
,
47
g
): Branching distally.
Discussion.
The second instar of a species of
Pseudophilomedes
has not been described previously. The specimen from Bottomly’s Blue Hole provided the opportunity to describe instar II of
P. ferulanus
.
The morphology of the first antenna and sixth limb of the species is consistent with members of the
Myodocopina
in that the fourth segment of the first antenna bears only a dorsal bristle, and the sixth limb bears only one bristle (see
Hiruta 1983: 673
). The bristle of the sixth limb of instar II of
P. ferulanus
is unusually long.