Dantya heardi Kornicker 1986

Dantya heardi

ETYMOLOGY.—The species is named for Richard W. Heard, who supplied some specimens.

HOLOTYPE.—USNM 193083, 1 ovigerous female in alcohol.

TYPE-LOCALITY.—Southwest Florida continental shelf, sta 2104.

PARATYPES.—Southwest Florida shelf: sta 37: 1 A–1 male, USNM 158838; 2 juveniles, USNM 193084; 1 female + 2 juveniles, USNM 193085; 1 juvenile male, USNM 193088. Sta 2101: 1 ovigerous female, USNM 193089. Sta 2104: 1 ovigerous female, USNM 158730; 1 juvenile male, USNM 158725; 3 juveniles, USNM 193087; 1 juvenile, USNM, 193090.

DISTRIBUTION.—Continental shelf off southwest Florida; depth 10–148 m (Figure 1, Table 1).

DESCRIPTION OF ADULT FEMALE (Figures 6–8).—Carapace elongate with well developed rostrum and caudal process (Figure 6); rostrum forming right-angle with anterior edge of valve ventral to rostrum; dorsal margin with distinct angles at anterior and posterior ends of hingement and linear along extent of hinge; ventral margin broadly convex and overhanging valve edge; anterior part of medial side of rostrum forming part of shell exterior and bearing 2 bristles (Figure 7a)

Ornamentation (Figure 6): Horizontal rib extending from ventral edge of rostrum to angle forming posterior end of hinge; second horizontal rib extending from anteroventral corner of valve to point on ventral margin anterior to caudal process (this ridge intersecting lower edge of adductor muscle attachment area); third rib lying just within ventral margin of valve; fourth rib extending from dorsal edge of rostrum to posterodorsal margin in vicinity of posterior end of hinge and lying just within dorsal margin of valve; rib along ventral edge of rostrum dividing in vicinity of inner end of incisur to form 2 branches, 1 extending to anterior margin of valve in vicinity of second horizontal rib, other branch continuing posteriorly to vicinity of central adductor muscle attachments and then bending ventrally to intersect second horizontal rib; vertical rib connecting first and second horizontal ribs in posterior part of valve anterior to caudal process. Carapace with numerous fossae bearing minute spines (see detail in Figure 6); surface of valves between fossae and on ribs with spines smaller than those in fossae. Long bristles present along ventral margin of valve and sparsely distributed on lateral surface.

Infold (Figure 7a,b): Infold of rostrum with 4 spinous bristles along anterior; 2 small bristles at inner edge of incisur (Figure 7a); infold of caudal process with 9 broad spinous bristles forming row near anterior part of process; inner margin of infold anterior to caudal process with 1 dorsal and 3 ventral bristles and 2 bristles near ventral margin of valve (Figure 7b).

Selvage: Anterodorsal margin and anteroventral margin with broad lamella prolongation with hirsute fringe; fringe apparently absent on selvage along ventral margin; lamella prolongation absent on rostrum in vicinity of the 4 spinous bristles and along posterior edge of caudal process (Figure 7a).

Central Adductor Muscle Attachments: Consisting of about 20 ovoid attachments; these differ from fossae on valve in not having minute spines.

Size: USNM 158730, length 1.61 mm, height 0.84 mm; USNM 193083, length 1.68 mm. height 0.90 mm; USNM 193085, length 1.53 mm, height 0.90 mm; USNM 193089, length 1.67 mm, height 0.84 mm.

First Antenna (Figure 8a): First joint bare. Second joint: medial surface with spines forming rows; lateral surface with spines forming row along distal margin; dorsal margin with spinous bristle. Third joint short, not separated from fourth joint by suture, with 2 bristles, 1 ventral, 1 dorsal. Fourth joint elongate, with 3 bristles, 2 ventral, 1 dorsal. Fifth joint elongate; sensory bristle with 6 short marginal filaments and spine at tip. Sixth joint minute, fused to fifth joint, with spinous medial bristle about length of sensory bristle of fifth joint. Seventh joint: a- bristle spinous, slightly longer than bristle of sixth joint; b-bristle slightly longer than a-bristle, with 1 short marginal filament and spine at tip; c-bristle about same length as sensory bristle, with about 4 short marginal filaments and minute spine at tip. Eighth joint: d- and e- bristles about same length as sensory bristle, bare with blunt tips; f-bristle with 6 short marginal filaments (tip broken off on illustrated limb); g-bristle about same length as sensory bristle, with 6 short marginal filaments and spine at tip.

Second Antenna (Figure 8b): Protopodite bare. Endopodite 2-jointed: first joint with 2 short proximal anterior bristles; second joint with long spinous terminal bristle. Exopodite: first joint with minute medial bristle bent at right-angle; joints 2–8 with slender spines forming row along distal margins; joints 4–8 with basal spines increasing in size on distal joints; basal spine of eighth joint longer than small ninth joint; bristles of joints 2–8 long, with 6–8 stout proximal ventral spines and distal natatory hairs; rings bearing spines longer than those bearing hairs; ninth joint with 3 bristles (1 long bristle with 6 proximal ventral spines and distal natatory hairs, 2 small with short slender hairs).

Mandible (Figure 8c): Coxale with hirsute ventral margin; endite well developed, with long proximal hairs. Basale: dorsal margin with midbristle reaching past end of joint and 2 terminal bristles (proximal of these about length of other); medial side with 2 small bristles near ventral margin; lateral side with 2 or 3 small bristles forming row near ventral margin; ventral margin with 4 small bristles. Exopodite minute, with 1 terminal bristle reaching past midlength of dorsal margin of first endopodial joint. First endopodial joint: dorsal margin with slender spines forming terminal row extending onto lateral surface; ventral margin with 1 small bristle and 2 long spinous claws. Second endopodial joint: dorsal margin with 4 bristles near midlength; lateral side with pectinate, unringed, short, claw-like bristles near middle of distal margin; ventral margin with 2 stout claws (proximal claw with slender ventral and dorsal spines; distal claw with 3 or 4 slender teeth and 1 stout tooth proximally on ventral margin); slender spines forming row on joint between proximal and distal claws. Third endopodial joint with 2 long claws, 1 shorter dorsal claw (tip broken on illustrated limb), and 2 ventral bristles.

Maxilla (Figure 8d): Three endites present: endite I with 6 terminal bristles; endite II with 2 proximal and 3 or 4 terminal bristles; endite III with 2 proximal and 3 or 4 terminal bristles. Coxale with 1 hirsute dorsal bristle. Basale with 1 or 2 distal bristles. Exopodite minute, with 1 spinous bristle. Endopodite: first joint with hairs along outer margin, 1 spinous alpha-bristle and I spinous beta-bristle (beta-bristle stouter than alpha-bristle); end joint with 2 fairly long spinous a-bristles, 1 shorter spinous c-bristle, and 5 stout, pectinate, terminal bristles.

Fifth Limb (Figure 8e,f): Three endites present: endite I with 2 spinous bristles; endite II with 1–4 bristles, endite III with 6 bristles. Exopodite (interpretation uncertain): first exopodial joint with 3 marginal bristles; second exopodial joint consisting of stout squarish tooth with 2 bristles along inner edge; third joint obscure but seemingly with 1 bristle on inner lobe and 1 on outer lobe; fused fourth and fifth joints with 3 bristles.

Sixth Limb (Figure 8g): Three endites present: endites I and II each with 2 short spinous bristles; endite III with 4 or 5 spinous bristles; endite IV with 5 or 6 spinous bristles. End joint hirsute, with 8 spinous or hirsute bristles; a single ringed bristle on posterior margin.

Seventh Limb (Figure 8h): Each limb with 3 or 4 proximal bristles (1 or 2 on each side), and 6 terminal bristles (3 on each side); each bristle with 3–8 bells. Terminus consisting of comb with about 6 alate teeth opposite 2 small pegs.

Furca: Each lamella with 6 claws; claw 1 fused to lamella, remaining claws separated from lamella by sutures; claw 4 stouter than claw 3; anterior of lamella proximal to claw 1 hirsute; each claw with teeth along posterior margin. Furca similar to that of D. magnifica (Kornicker and Cohen, 1978: fig. 4d).

Bellonci Organ (Figure 7d): Elongate with 11 proximal sutures and rounded tip bearing spine. Hairs forming row along distal margins of segments visible under oil immersion.

Eyes (Figure 7d): Medial eye bare, pigmented brown. Lateral eye about same size as medial eye, with 4 or 5 amber ommatidia.

Upper Lip (Figure 7c): Consisting of left and right lobe, each with undulating margin and slender spines forming rows (both lobes shown on illustrated lip). A single stout tooth projecting anteriorly between lobes.

Genitalia: Consisting of small sclerotized ring on each side of body anterior to furca.

Y-Sclerite: Typical for genus.

Eggs: USNM 158730 with 3 well-developed eggs in marsupium as well as large unextruded undeveloped eggs; USNM 193083 with 4 eggs in marsupium; USNM 193089 with 2 eggs in marsupium.

COMPARISONS.—The carapace of D. heardi resembles that of D. magnifica in that the rostrum forms a right angle with the anterior part of the valve ventral to the rostrum. On other species of Dantya the rostrum overhangs the incisur. The carapace of D. heardi does not have the numerous knob-like processes present on the carapace of D. magnifica. The upper lip of D. heardi bears a stout anterior process (Figure 7c) not present on the upper lip of D. magnifica.

DISTRIBUTION.—Same as for Sarsiellidae.

Insufficient information is available to refer several species to genera, although they probably belong in either Sarsiella or Eusarsiella as emended herein. These species are Eusarsiella guttata Poulsen (1965:123), Sarsiella simplex Brady (1890:516), and S. carinata Scott (1905:368). I refer to the category “Genus and Species Indeterminate,” two species known only from external views of the carapace: Sarsiella rudis Brady (1907:517), and S. foveata Brady (1890:517), both members of the Sarsiellinae.

Bonaduce et al. (1983:478), in a paper dealing with ostracodes from the Red Sea state, “Some specimens pertaining to the myodocopid genera Anchoenia [Ancohenia], Rutiderma, and Sarsiella were found in these samples but not discussed because of the scattered and rare findings.” In figure 2 of that paper SEM micrographs of the carapaces of three specimens are presented: Ancohenia(?) sp. 1 (fig. 2:1–3); Rutiderma(?) sp. (fig. 2:4); and Sarsiella sp. 1 (fig. 2:5). At my request Dr. Bonaduce kindly forwarded for my examination representatives of the three illustrated species. A dry slide labeled “?Ancohenia n. sp., Red Sea, St. 5, Jackson Reef, 36 m, L = 0.75, H = 0.58” contained a left and right valve and also dried soft parts. I chemically treated the soft parts and mounted them in glycerine on a glass slide. The valves of the specimen examined do not appear to have a carbon or metallic coating usually used when taking SEM micrographs, and therefore, may not be the illustrated specimen (fig. 2:1–3). In my opinion, however, the specimens are conspecific. The specimen I examined is the first instar of a cylindroleberid, which I herewith refer to Actinoseta sp. Because of the immaturity of the specimen examined the generic referral must be considered tentative. The microstructures on the carapace of the species (fig. 2:3) indicate that it may be an undescribed species. Another dry slide labeled“? Rutiderma, Red Sea, N3, L = 0.63, H = 0.25” contained the coated valve illustrated in Bonaduce et al. (1983, fig. 2:4). In medial view the valve has a long straight dorsal margin having what appears to be a socket at each end. I cannot relate the valve to any known myodocopid, and therefore, refer it herewith to the category “incertae sedis.” A third slide labeled “Sarsiella sp. 1, L = 0.62, H = 0.52, Red Sea, St. 5, Jackson Reef, 36 m” bears an uncoated right valve having appendages within it, and also, a small, coated shell fragment of presumably the left valve. The left valve is illustrated by Bonaduce et al. (1983, fig. 2:5) and is probably the left valve of the specimen I received. I herewith refer the species to Rutiderma sp.