Postasterope abaco Kornicker 1986

Postasterope abaco

ETYMOLOGY.—The specific name from the island near which the holotype was collected.

HOLOTYPE.—USNM 158388, adult male, partly dissected, in alcohol.

TYPE-LOCALITY.—Abaco Island, Bahamas.

PARATYPE.—USNM 158387, 1 adult male; USNM 158602, 8 adult males, all from same sample as holotype.

DISTRIBUTION.—Known only from type-locality.

DESCRIPTION OF ADULT MALE (Figures 45, 46).—Carapace elongate, only slightly narrower posteriorly in lateral view (Figure 45a,b): bristles forming vertical row near posterior end of valves.

Infold (Figure 45c,d): Similar in construction to that of Parasterope corrugata Poulsen, 1965:391, and Synasterope setisparsa illustrated herein.

Size: USNM 158387, length 1.48 mm, height 0.76 mm; USNM 158388, length 1.55 mm, height 0.81 mm. USNM 158602 (3 specimens measured): length 1.50 mm, height 0.74 mm, length 1.52 mm, height 0.76 mm, length 1.49 mm, height 0.75 mm.

First Antenna (Figure 45e): 1st joint with medial spines forming rows. 2nd joint with medial spines forming rows near ventral margin, and 1 spinous dorsal bristle; lateral bristle absent. Suture between 3rd and 4th joints better defined on medial than on lateral surface; 3rd joint with small bristle on short ventral margin, and 6 spinous bristles on long dorsal margin; 4th joint with minute spines forming rows on lateral surface near ventral margin, 2 terminal ventral bristles, and 1 long, spinous, dorsal bristle. Short 5th joint with stout sensory bristle with abundant filaments (terminal filaments stouter than others). 6th joint with undulate dorsal margin having 2 prominent proximal processes; medial bristle of 6th joint spinous, with base near dorsal margin. 7th joint: a-claw with few spines along ventral margin and few faint teeth on medial surface (a-claw missing on illustrated limb, but shown as dashed outline of claw on opposite limb); b-bristle with 5 or 6 marginal filaments, some with spines; c-bristle very long, with about 27 marginal filaments. 8th joint: d-bristle absent; e-bristle about same length as b-bristle, bare with blunt tip; f-bristle about same length as c-bristle, with about 25 ventral filaments; g-bristle longer than b-bristle, with 8 marginal filaments; 7 long lateral hairs present on joint just proximal to base of g-bristle.

Second Antenna: Protopodite bare except for minute, distal, medial bristle. Endopodite 3 jointed (Figure 45f): 1st joint elongate, bare; 2nd joint elongate, with 3 ventral bristles (distal of these length of others); 3rd joint elongate, reflexed on 2nd, with long proximal bristle with blunt tip; tip of joint pointed and bearing ridges. Exopodite: 1st joint elongate, with long hairs forming few distal rows; 2nd joint about three times length of 3rd joint; joints 3–9 gradually decreasing in size; bristles of joints 2–8 with natatory hairs; 9th joint with 4 bristles (3 long, 1 short, all with natatory hairs); joints 2 or 3 to 8 each with minute basal spine (some spines with blunt tips); joints 2–8 with faint short spines and long hairs along distal margins; 9th joint with minute, blunt lateral spine; medial distal bristle not observed on 1st joint but could be present.

Mandible (Figure 46a): Coxale endite: slender medial bristle present near base of ventral branch; ventral branch with spines forming 4 oblique groups, and pointed tip with several minute spines; ventral margin of dorsal branch with 4 small processes and short main spine; tip of dorsal branch with slender terminal spine (broken off on illustrated limb but present on opposite limb of same specimen); dorsal margin of branch with distal bristle set back from tip of branch (broken off on both limbs of USNM 158387). Basale endite with 4 end-type bristles, 3 triaenid bristles with 2–4 sets of paired marginal teeth excluding terminal pair, 1 dwarf bristle, and glandular peg. Basale: dorsal margin with 2 long subterminal bristles; medial surface with 1 short triaenid bristle with 3 pairs of marginal spines excluding terminal pair and 1 minute spine-like bristle, both near ventral margin. Exopodite reaching past middle of dorsal margin of 1st endopodial joint, hirsute, with 2 short subterminal bristles. 1st endopodial joint with 3 long, spinous, ventral bristles. 2nd endopodial joint: dorsal margin with 2 proximal bristles, and stout a-, b-, c-, and d-bristles; ventral margin with 3 long, spinous, terminal bristles; medial side with spines forming rows, 1 cleaning bristle between b- and c-bristles, 4 cleaning bristles forming oblique row near base of c-bristle, and 1 short spinous bristle near base of d-bristle; lateral side with 1 long spinous bristle between b- and c-bristles and between c- and d-bristles (none between b- and c-bristles on right limb of USNM 158387). End joint with straight dorsal claw with few lateral teeth near ventral margin, and 5 bristles (medial of these short).

Maxilla (Figure 45g): Epipodial appendage with pointed hirsute tip. Endite I with 3 bristles (2 long, stout, 1 small, medial); endite II with 3 long stout bristles. Basale: medial side hirsute, with 2 short bristles near dorsal margin; lateral side with 1 small proximal bristle; ventral margin with 1 short proximal bristle, 1 small distal bristle, and 1 long, spinous, terminal bristle. Endopodite: 1st joint with small proximal protuberance and midbristle on anterior margin, and long beta-bristle; end joint with long terminal bristle (lengths of beta-bristle and terminal bristle on illustrated limb obtained from opposite limb of same specimen).

Fifth Limb (Figure 46b): Comb with long, stout, spinous, exopodial bristle reaching just past tip of comb; 2 slender bristles present ventral and distal to base of stout exopodial bristle, and 2 pairs of bristles closer to ventral margin; hairs present along terminal margin of comb, and row of short and long bristles present along ventral margin.

Sixth Limb (Figure 46c): Anterior margin with 1 upper and 1 lower endite bristle; anterior corner of skirt with 2 bristles (longer of these two to two and one-half times length of other); ventral margin of skirt with 2 small bristles near middle and 1 or 2 short bristles on posterior corner; lateral flap hirsute but without bristles.

Seventh Limb (Figure 46d): Proximal group with 6 bristles (3 on each side); distal group with 6 bristles (3 on each side); bristles with 2–4 bells. Terminus consisting of opposing combs, each with about 9 spinous teeth (spines not shown on illustrated limb).

Furca (Figure 45i): Each lamella with 8 bristles, (posterior 2 of these bristle-like but not oriented backwards); main claws with short and long teeth forming row along posterior edge; claw 1 of right lamella located anterior to claw 1 of left lamella.

Bellonci Organ (Figure 45h): Elongate, broadening in middle, with rounded tip.

Eyes (Figure 45h): Medial eye unpigmented, with dorsal hairs. Lateral eye larger than medial eye, with amber pigment and 18–20 ommatidia. (Lateral eye was probably black prior to preservation.)

Upper Lip (Figure 45h): Paired lobes and lateral flaps hirsute; no spines observed.

Copulatory Organs: Each organ with 3 small terminal lobes.

Posterior of Body (Figure 45i): With elongate, hirsute, finger-like dorsal process.

Y-Sclerite: Typical for subfamily.

COMPARISONS.—The new species P. abaco differs from P. corrugata and P. messingi in having 3 instead of 4 bristles on endite I of the maxilla. Postasterope abaco also differs from P. corrugata in having a triaenid bristle rather than a simple bristle on the ventral margin of the mandibular basale. Postasterope abaco is considerably larger than P. messingi.