Pteromeniscus intesi Kornicker 1981

Pteromeniscus intesi

Asteropteron upsilon Kornicker and Caraion [part], 1974:61, figs. 34e–q, 36 [Instar II?].

HOLOTYPE.—USNM 156610, adult male, not dissected, in alcohol.

TYPE-LOCALITY.—Discovery station 7811.

ETYMOLOGY.—The species is named for Dr. A. Intes of the Centre de Recherches Oceanographiques, Abidjan, Ivory Coast.

PARATYPES.—USNM 150286B, 150286C, an adult male and a juvenile male, respectively, from same sample as holotype; USNM 150287A, USNM 150287B, an adult male and a juvenile female from Discovery station 7810.

DISTRIBUTION (Figure 125).—Continental slope of Mauritania at depths of 270–699 m.

DESCRIPTION OF ADULT MALE (Figures 13d, 164–167).—Carapace oval in lateral view except in vicinity of small incisure (Figures 164, 165a, 167a); viewed medially incisur forming small right angle; broad flange present just within and parallel to valve edge except opposite incisur; lateral ridge present with concave upper margin and with midpart ventral to central adductor muscle attachment area.

Ornamentation: Outer edge of lateral ridge consisting of pores forming 4 rows; similar pores forming rows present along outer edge of peripheral flange; long bristles abundant along valve edge and sparsely distributed on lateral surface; some of lateral bristles emerging from paired pores.

Infold: Anterodorsal infold with short bristle just above incisur and 25 long bristles forming row parallel to anterodorsal edge of valve; anteroventral infold with 10 bristles forming row parallel to anteroventral margin of valve; ventral infold with 3 bristles; posteroventral infold with about 41 long and short bristles; anteroventral and ventral infold with list bearing wide lamellar prolongation.

Selvage: Broad lamellar prolongation present along free margin of valve; prolongation fringed along ventral margin of valve.

Adductor Muscle Attachment Scars (Figure 167b): Consisting of about 15 individual ovoid scars.

Size: USNM 150286B, length 2.31 mm, height 1.79 mm; USNM 150287A, length 2.28 mm, height 1.65 mm; USNM 156610, length 2.47 mm, height 1.92 mm.

First Antenna (Figure 165b): 1st and 2nd joints with short spines and long hairs on medial and lateral surfaces; 2nd joint with 4 bristles at the middle of the dorsal margin; 3rd joint short with 1 ventral and 2 dorsal bristles; 4th joint short with 3 terminal bristles (2 ventral, 1 dorsal); 5th joint very short ventrally and almost same length as dorsal edge of 6th joint dorsally; sensory bristle of 5th joint with abundant thin filaments; 6th joint with slender medial bristle. Seventh joint: a-bristle about 3 times length of bristle of 6th joint, with rings on distal two-thirds; b-bristle slightly longer than a-bristle, with 3 marginal filaments and bifurcate tip; c-bristle longer than b-bristle, with 7 marginal filaments and bifurcate tip. Eighth joint: d- and e-bristle bare, d-bristle slightly shorter and more slender than e-bristle, e-bristle about same length as a-bristle; f-bristle longer than b-bristle but shorter than c-bristle, with 5 marginal filaments and bifurcate tip; g-bristle about same length as f-bristle, with 5 or 6 marginal filaments and bifurcate tip.

Second Antenna (Figure 165c,d): Protopodite with medial bristle and few short spines forming rows on dorsal half of medial surface. Endopodite 3-jointed: 1st joint bare; 2nd joint elongate with 3 or 4 distal ventral bristles (2 long, 1 or 2 short); 3rd joint reflexed with 1 long proximal bristle and knifelike tip; slot present on medial surface just proximal to tip. Exopodite: 1st joint with hairs forming 6 clusters on medial surface near ventral margin and minute, terminal, medial spine; 2nd joint about twice length of 3rd; bristle of 2nd joint reaching past 9th joint, with proximal spines and distal natatory hairs along ventral margin and just natatory hairs along dorsal margin; bristles of joints 3–8 with natatory hairs, some with faint ventral spines near middle; 9th joint with 3 bristles (2 long, 1 short), all with natatory hairs; joints 2–9 with short slender spines forming row along distal margin, no basal spines.

Mandible (Figure 165e–h): Coxale endite: minute bristle present medially near base of ventral branch; ventral branch spines forming about 7 oblique rows along ventral margin and tip with 2 stout teeth on ventral half and short faint spines on dorsal half (Figure 165g); ventral margin of dorsal branch with 3 or 4 low processes proximal to short main spine; tip of branch with 3 projections (Figure 165f): middle and ventral processes with short spines, dorsal process with long hirsute bristle; dorsal margin of dorsal branch with few serrations. Basale: endite with 2 long end bristles with numerous marginal spines, 5 triaenid bristles with about 12 pairs of marginal spines excluding terminal pair, and 1 dwarf bristle; ventral margin of basale with 6 triaenid bristles with 12–15 marginal spines excluding terminal pair (spines decrease in length distally along bristle) (Figure 165h); dorsal margin with 1 minute bristle and 2 long terminal bristles; medial and lateral surfaces with long hairs near dorsal margin. Exopodite hirsute, almost reaching distal margin of 1st endopodite joint, with 2 terminal bristles with short marginal spines. Endopodite: ventral margin of 1st joint with 7 spinous bristles; medial surface with few long hairs forming rows near dorsal margin; dorsal margin and medial surface of 2nd joint near dorsal margin with numerous bristles; ventral margin of 2nd joint with 3 spinous subterminal bristles (2 long, 1 medium); medial surface with numerous spines forming rows; end joint with 5 bristles (1 short ventral bristle with short marginal spines, 1 long, ventral, clawlike bristle, 1 long clawlike bristle at middle of terminal margin, and 2 medium dorsal bristles).

Maxilla (Figure 166a): Epipodial appendage long pointed, hirsute at tip and along dorsal margin; 2 short bristles present near base of adzlike bristle; endite I with 3 long bristles; endite II with 1 short and 3 long bristles; ventral margin of basale with long, spinous, terminal bristle with base on lateral side; dorsal margin and medial side hirsute; medial side with 1 medium terminal bristle near ventral margin and 1 short proximal bristle near middle; no exopodite observed but 1 short bristle present in its place. Endopodite: 1st joint hirsute with 1 short slender midbristle on dorsal margin and long beta-bristle with short marginal spines; end joint with 3 terminal bristles with short marginal spines.

Fifth Limb (Figure 166b): Epipodial appendage with 66 bristles; dorsal margin of comb bare except for hairs along terminal margin; lateral side of comb with 7 exopodial bristles: 1 long, distal, spinous bristle near dorsal margin, 1 longer, proximal, spinous bristle near ventral margin, and 5 short bristles between the 2 long bristles.

Sixth Limb (Figure 166c): No epipodial bristles present; anterior margin of narrow stem with about 19 bristles (1 medial, proximal, short, spinous; 12 short spinous with bases on anterior margin; 4 short, spinous, distal with bases on medial surface; 2 longer, spinous, distal with bases on medial surface near broad skirt); a short suture present at intersection of stem and skirt; anterior and ventral part of skirt with about 31 bristles; posterior end of skirt prolonged, with 1 short hirsute bristle; limb hirsute.

Seventh Limb (Figure 166d): Each limb with 11 bristles, 5 on one side, 6 on other; each bristle with 3–5 bells and no marginal spines; terminus with 8 spinous recurved teeth.

Furca (Figure 165i): Each lamella with 7 claws: claws 1 and 2 about same size, claws 3–7 decrease in size proximally along lamella; all claws with teeth along posterior margins; teeth decrease in size distally along claw.

Eyes and Rod-shaped Organ: Lateral eyes absent; medial eye unpigmented, hairs not observed (Figure 166e); rod-shaped organ narrow in middle part, tip rounded (Figures 166e, 167c).

Upper Lip (Figure 166f,g): Consisting of 2 rounded hirsute lobes, each with long, stout, anterior process with marginal spines; hirsute lateral flaps present.

Posterior of Body (Figures 166h, 167d): Posterior hirsute with hirsute, thumblike, dorsal process.

Genitalia: Copulatory organ minute.

Gills (Figure 167d): Well developed, long, narrow.

Y -Sclerite (Figure 166i): Typical for family.

Parasites: USNM 156610 with cyproniscid isopod in marsupium.

DESCRIPTION OF FEMALE (Instar III) (Figures 168, 169, Plates 176–179).—Carapace oval in lateral view (Figure 168a, Plate 176a); anterior with minute incisur forming right angle; broad concentric flange present just within edge of valve except in vicinity of incisur where it forms right angle (Plate 176b); curving ridge with concave upper edge present with middle of ridge ventral to central adductor muscle attachments (Plates 176a, 177c).

Ornamentation: Carapace with peripheral flange and subcentral ridge described above; edge of flange and subcentral ridge with several rows of pores; outer and inner edges of pores tending to be convex; other edges linear (Plates 176c–e, 177d); surface between flange and ridges smooth with some visible reticulations (Plate 176f); bristles abundant along valve edge and sparsely distributed on lateral surface; lateral bristles emerging from open pores with marginal lip, some paired (Plates 177a, b).

Infold (Plate 178): Anterodorsal infold with 15 bristles forming row; anteroventral infold with 2 bristles ventral to incisur (Figure 168c); list present along ventral margin with anterior end just ventral to the 2 anteroventral bristles below incisur; anterior part of list with wide lamellar prolongation with smooth edge; posterior end of lamellar prolongation unknown, but prolongation continues at least to middle of ventral margin; ventral infold with 1 or 2 bristles; posteroventral infold with about 22 bristles and small processes, some of the bristles and processes tubelike with open ends, some bristles paired (Figure 168d, Plate 178b–f).

Selvage: Broad lamellar prolongation along free margin of valve; prolongation fringed along ventral margin of valve (Figure 168d, Plate 178a).

Adductor Muscle Attachment Scars (Figure 168b): Consisting of about 16 individual oval scars.

Size: USNM 150287B, length 1.89 mm, height 1.54 mm.

First Antenna (Figure 169a): 1st and 2nd joints hirsute; 2nd joint with 2 spinous bristles near middle of dorsal margin; 3rd joint short, with 1 ventral and 2 dorsal bristles, all spinous; medial side of 3rd joint with few minute spines; 4th jo with 2 spinous terminal bristles (1 ventral, dorsal); 5th joint about equal in length to combined lengths of 3rd and 4th joints, with hairs on medial surface; sensory bristle of 5th joint with 2 very small proximal filaments, 1 long filament near middle reaching tip of stem, and 3 shorter terminal filaments including tip of stem; 6th joint very short, with hairs on lateral surface, and medial bristle with length about 55 percent length of joints 5–7. Seventh joint: a-bristle long, bare, with pointed tip; b-bristle about three and three-quarters length of bristle of 6th joint, with 1 short proximal filament and 1 minute spine or filament near tip; c-bristle about same length as b-bristle, with 4 proximal filaments and 1 near tip. Eighth joint: d- and e-bristles bare, d-bristle slightly shorter than e-bristle, e-bristle slightly shorter than a-bristle; f-bristle longer than a-bristle but shorter than c-bristle, with 3 proximal filaments and 1 near tip; g-bristle about same length as f-bristle, with 3 proximal filaments and 1 minute filament near tip.

Second Antenna (Figure 169b): Protopodite with medial bristle with short marginal spines; few short spines forming rows on dorsal half of medial surface. Endopodite 3-jointed: 1st and 2nd joints short, bare; 3rd joint elongate, hirsute, with long terminal bristle. Exopodite: 1st joint with minute, terminal, medial spine; 2nd joint about same length as 3rd joint; bristles on joints 2–8 with faint slender spines near middle of ventral margin, and natatory hairs all along ventral and posterior margins; 9th joint with 3 bristles (2 long, 1 short), all with natatory hairs; joints 2–9 with short, slender spines forming row along lateral side of distal margin, no basal spines.

Mandible: Coxale endite: tip of dorsal branch broken off on both limbs of USNM 150287B, otherwise endite similar to that of adult male. Basale: endite with 2 end bristles (1 long, 1 short) with short marginal spines, 3 triaenid bristles (the proximal of these longer than others, and with few slender proximal hairs or spines), each with 10–11 pairs of spines excluding terminal pair (spines decrease in length distally along bristle), and 1 dwarf bristle distal to proximal triaenid bristle; ventral margin of basale with 2 triaenid bristles with 11 pairs of spines excluding terminal pair, and widely spaced, slender, proximal hairs or spines; dorsal margin of basale with 2 long, spinous, terminal bristles; 1 minute bristle present on medial surface close to terminal bristles of dorsal margin; medial surface with long hairs forming rows on dorsal half; lateral surface with long hairs forming rows near both dorsal and ventral margins. Exopodite hirsute, about two-thirds length of dorsal margin of 1st endopodial joint, with 2 terminal bristles with short marginal spines (outer bristle slightly shorter than inner bristle, both similar in length to those of adult male). Endopodite: ventral margin of 1st joint with 4 spinous bristles; medial surface of 1st joint bare; dorsal margin of 2nd joint with 2 long spinous bristles proximal to middle, and 5 spinous subterminal bristles (2 or 3 of these with bases on medial side; one of the medial bristles of triaenid type); medial surface of 2nd joint with numerous long spines forming rows; dorsal margin of 2nd joint with 2 spinous bristles of equal length (lateral of these more slender than other); end joint with 5 bristles similar to those of adult male.

Maxilla and 5th Limb: Similar to that of adult male.

Sixth Limb: No epipodial bristles present; anterior margin of narrow stem with 12 bristles (1 medial, proximal, short, spinous; 7 short spinous with bases on anterior margin; 2 short, spinous, distal, with bases on medial surface near broad skirt; 2 longer, spinous, distal, with bases on medial surface near broad skirt); a suture present at anterior intersection of stem and skirt; anterior, rounded margin of lateral flap with 6 hirsute bristles; ventral margin of skirt with 11 bristles, either hirsute or with long proximal hairs and short distal spines; posterior end of skirt with 1 short hirsute bristle similar to that of adult male.

Seventh Limb: Elongate but without bristles; terminus consisting of 2 lobes without teeth.

Furca (Figure 169c): Each lamella with 5 claws; claws 1 and 2 about same size; claw 3 slightly shorter than claw 2; claws 4 and 5 short; all claws with teeth along posterior margins.

Eyes and Rod-shaped Organ (Figure 169d): Lateral eyes absent; medial eye unpigmented, bare; rod-shaped organ with weak suture near middle, tip rounded.

Upper Lip (Figure 169e,f, Plate 179): Consisting of 2 rounded, hirsute lobes, each with long, stout, anterior process; hirsute lateral flaps present.

Gills: Well developed, long, narrow.

Y-Sclerite (Figure 169h): Typical for family.

Omegasterope, new genus

TYPE-SPECIES.—Asteropteron upsilon Kornicker and Caraion, 1974, monotypic.

ETYMOLOGY.—The generic name is derived in part from the Greek Omega, in reference to the similarity of the lateral ridge on the carapace of the type-species to the capital of the Greek letter. Gender feminine.

DISTRIBUTION.—Continental shelf off Mauritania at depths of 35–82 m (Figure 125).

DISTRIBUTION.—Continental shelf of Mauritania at depths of 35–82 m (Figure 125).