Synasterope hirpex Kornicker 1989

Synasterope hirpex

Synasterope species A.—Kornicker, 1985:410–412.

Parasterope species B.—Kornicker, 1985:410–412 [part, only specimen from sample DS–55].

ETYMOLOGY.—From the Latin hirpex (rake, harrow).

HOLOTYPE.—Adult female, length 1.50, in alcohol, MNHN Os 258, Museum National d'Histoire Naturelle, Paris, France.

TYPE LOCALITY.—BIOGAS VI, R.V. Jean Charcot, west of Bay of Biscay, 46°31′12″N, 10°23′48″W, 4706 m, sta 4, sample DS-78, 25 Oct 1974.

PARATYPES.—BIOGAS IV, R.V. Jean Charcot, sta 3: sample DS–55 1 A-1 male (length 1.36 mm, height 0.74 mm). BIOGAS V, R.V. Cryos, sta 4: sample DS–68, 1 juvenile male (USNM 193258). BIOGAS VI, R.V. Jean Charcot, sta 4: sample DS–78, 1 adult female on slide and in alcohol (USNM 193256); sample DS–79, 1 adult male on slide and in alcohol (USNM 193257).

DISTRIBUTION.—West of Bay of Biscay, 4125–4715 m.

DESCRIPTION OF ADULT FEMALE (Figures 60, 61).—Carapace elongate in lateral view with subparallel ventral and dorsal margins; inner end of incisur near midheight (Figure 60a, b).

Infold (Figure 60b): Anterodorsal infold including rostrum with about 120 long and short bristles (Figure 60b); a single bristle at inner end of incisur; broad part of anteroventral infold ventral to incisur with about 40 short and long bristles; ventral infold between broad anteroventral infold and anterior end of broad posteroventral list with about 27 bristles. Broad posteroventral list with 17 flap-like bristles and 13 small bristles (not more than 1 bristle between each pair of flap-like bristles); 1 or 2 bristles present between ventral end of broad posteroventral list and valve edge; right valve only with small bristle near posterior juncture just dorsal to end of broad posteroventral list.

Selvage: Broad lamellar prolongation (with long fringe) along inner half of lower margin of incisur. Short segment with long fringe present near posterior juncture just anterior to single bristle on right valve. Elsewhere lamellar prolongation narrow and without marginal fringe.

Size: Holotype, length 1.50 mm, height 0.90; USNM 193256, length 1.57 mm, height 0.88 mm.

First Antenna (Figure 60c): 1st joint with medial and lateral spines and hairs. 2nd joint with medial, lateral, and ventral spines and 1 spinous dorsal bristle. Suture between 3rd and 4th joints distinct on lateral side but on medial side distinct only in ventral third; 3rd joint with small bare slender ventral bristle and 6 dorsal bristles forming 5 groups of 1, 1, 1, 1, and 2 bristles; lateral bristle of distal pair with short marginal spines, others with long proximal and short distal spines. 4th joint with long spinous dorsal bristle and 2 ventral bristles (1 long, spinous, 1 very short, bare). Distal dorsal corner of 5th joint with spines forming lateral row extending onto dorsal margin; sensory bristle with stout proximal part and 6 distal filaments. 6th joint with long medial bristle with short marginal spines. 7th joint: a-bristle claw-like, with minute distal teeth along ventral margin; b-bristle longer than a-bristle, with 3 distal filaments excluding stem, some with marginal spines; c-bristle long, with 5 marginal filaments. 8th joint: d-bristle absent; e-bristle about same length as b-bristle, bare with blunt tip; minute lateral pore present on small pedistal forming base for e-bristle; f-bristle bent dorsally, with 4 short marginal filaments; filaments of f-bristle and stem between 3rd and 4th filaments with short marginal spines.

Second Antenna (Figure 60d): Protopodite with medial spines forming rows, and very small distal medial bristle. Endopodite with 3 well-defined joints; terminal filament slightly longer than stem. Exopodite: 1st joint with long hairs forming distal rows, but with no distal medial bristle or spine; 2nd joint about twice length of 3rd; bristle of 2nd joint reaching to about 9th joint, with densely spaced hair-like spines along ventral margin; bristles of joints 3–8 with natatory hairs, but no spines; 9th joint with 1 long bristle with natatory hairs, 1 bristle about same length as combined length of joints 6–9 and with short, faint, marginal hairs, and 1 short bristle about same length as combined length of joints 8 and 9 and either bare or with indistinct, short, marginal spines; 2nd joint with minute spines forming 2 rows; 1 near distal end and 1 just distal to midlength; joints 3–8 with minute spines forming distal row; basal spines absent; spines forming row in place of lateral spine of 9th joint.

Mandible (Figure 60e,f): Coxale endite: ventral branch with spines forming 3 oblique rows and terminal end with 3 minute teeth; small medial bristle near base of branch; ventral margin of dorsal branch with 4 paired processes followed by 4 single processes and main spine; dorsal margin of branch serrate opposite processes on ventral margin; terminal end of branch missing on both endites of specimen examined; medial surface of coxale proximal to endite with numerous spines forming rows. Basale endite with 4 end bristles, glandular peg, 2 dwarf bristles, and 2 triaenid bristles (proximal with about 15 paired marginal spines). Basale: dorsal margin with short bare midbristle and 2 long terminal bristles with short marginal spines; ventral margin with U-shaped depression but no bristles; medial surface without spines. Exopodite hirsute distally, with 2 small subterminal bristles not quite reaching distal end of dorsal margin of 1st endopodial joint. 1st endopodial joint with 3 spinous ventral bristles. 2nd endopodial joint: ventral margin with 3 long spinous terminal bristles; dorsal margin with small proximal bristle and 4 stout spinous a-, b-, c-, and d-bristles; medial surface with spines forming rows, 1 cleaning bristle between a- and b-bristles and between b- and c-bristles, 4 cleaning bristles forming oblique row near base of c-bristle, and 1 long spinous bristle with base distal to d-bristle; lateral side without bristle between b- and c-bristles and with long spinous bristle between c- and d-bristles. End joint with stout terminal claw (with proximal spines on ventral margin, and widely separated spines on dorsal margin) and 5 bristles.

Maxilla (Figure 61a): Endite I with 4 bristles (3 long, 1 short); endite II with 3 long bristles. Basale: hirsute; lateral side with 1 small proximal bristle; medial side near dorsal margin with 1 short proximal bristle and 1 longer distal bristle; ventral margin with 1 proximal bristle, 1 small distal bristle, and 1 long spinous terminal bristle. 1st endopodial joint with small anterior bristle and long terminal bristle; end joint with long terminal bristle extending past terminal bristle of 1st joint. Epipodite broken off both limbs of specimen examined.

Fifth Limb (Figure 61b): Comb: exopodial bristle extending past tip of comb; 1 slender bristle just ventral to base of exopodial bristle and 5 bristles near ventral margin of comb.

Sixth Limb (Figure 61c): Trunk with small medial bristle in proximal anterior corner; anterior margin with no bristle at lower suture and 4 bristles just dorsal to proximal suture. Skirt with 4 small bristles at anterior end and 12 hirsute bristles along ventral and posteroventral margin; lateral flap with hairs but no bristles. Limb hirsute.

Seventh Limb (Figure 61d): Proximal group with 7 bristles (3 or 4 on each side); distal group with 6 bristles (3 on each side); all bristles with 1–4 bells. Terminus comprising 2 opposing combs, each with 3 or 4 poorly defined teeth.

Furca (Figure 61e): Each lamella with 8 claws (posterior 2 bristle-like but not oriented backwards); claw 1 of right lamella slightly anterior to claw 1 of left lamella; claws 1–4 with hairs along anterior margin (hairs especially long on claw 1); teeth along posterior margins of claws 1–6 extremely fine.

Bellonci Organ (Figure 60g): Elongate, cylindrical with rounded tip.

Eyes (Figure 60g): Lateral eyes absent. Medial eye hirsute dorsally, without pigment.

Upper Lip (Figure 60g): Lobes hirsute but without spines; saddle between lobes without spines; hirsute flap on each side of mouth.

Posterior of Body (Figure 61e): Long hairs present near midheight and at posterodorsal corner; posterodorsal corner broadly rounded and with spines forming rows.

Genitalia (Figure 61e): Oval ring on each side of body.

Y-Sclerite (Figure 61e): Typical for subfamily.

Eggs (Figure 60a): USNM 193256 with single egg in marsupium.

DESCRIPTION OF ADULT MALE (Figures 62, 63).—Carapace larger than that of female, with more open incisur and with narrower posterior when viewed laterally (Figure 62a). Hairs forming vertical row near posterior end (Figure 62a).

Infold: Not examined.

Size: USNM 193257, length 1.80 mm, height 0.97 mm.

First Antenna (Figure 62b): 1st joint with few medial spines forming rows. 2nd joint with medial, lateral, and ventral spines forming rows and 1 spinous dorsal bristle. 3rd joint separated from 2nd and 4th joints by sutures better defined on medial side than on lateral side; trapezoid in shape; ventral margin with small bristle; dorsal margin with 6 bristles forming 5 groups of 1, 1, 1, 1, and 2 bristles on right limb and 4 groups of 1, 1, 2, and 2 on left limb, all with long proximal spines (spines of lateral bristle of distal pair thinner than spines of medial bristle). 4th joint with 1 spinous dorsal bristle and 2 ventral bristles (medial about half length and much thinner than lateral). Sensory bristle of short 5th joint stout and with abundant filaments (filaments not shown on illustrated limb). Medial bristle of long 6th joint spinous and about same length as combined length of joints 6–8. 7th joint: a-bristle claw-like, with indistinct distal spines on ventral margin; b-bristle about 5 times length of a-bristle, with 4 marginal filaments; c-bristle very long (about 5 times length of b-bristle), with about 18 marginal filaments. 8th joint: d-bristle minute; e-bristle about twice length of a-bristle, bare with blunt tip; f-bristle similar to c-bristle (broken off on illustrated right limb but present on left limb of specimen examined); g-bristle about twice length of b-briste, with 6 marginal filaments.

Second Antenna (Figure 62c): Prodopodite with few medial spines forming rows near ventral margin posterior to endopodite and with small medial distal bristle. Endopodite 3-jointed: 2nd joint with 3 small distal bristles; 3rd joint with proximal filament and serrate inner margin, especially near tip. Exopodite; 1st joint with distal medial spines forming rows but without terminal medial bristle. 2nd joint about same length as combined lengths of joints 3–6; bristle of 2nd joint and bristles of joints 3–8 long with natatory hairs; 9th joint with 4 bristles (3 long, 1 short), all with natatory hairs; joints 2–8 with long hairs forming distal row near inner edge and smaller hairs or spines forming medial and lateral rows along distal margins; basal spines and lateral spine of 9th joint absent.

Mandible (Figure 62d,e): Coxale endite: small medial bristle at base of ventral branch; ventral branch with spines forming 4 oblique rows and tip with 3 minute teeth (ventral longer than others); ventral margin of dorsal branch with 6 paired processes and 3 single processes proximal to main spine; tip of branch with slender hirsute bristle; dorsal margin of branch with hirsute bristle set back from tip of branch, and with serration opposite processes of ventral margin. Basale and 1st endopodial joint similar to those of female. Exopodite reaching to about midlength of dorsal margin of 1st endopodial joint, hirsute distally, and with 2 small terminal bristles. 2nd endopodial joint: ventral margin with 3 long spinous terminal bristles; dorsal margin with 2 short proximal bristles and stout spinous a-, b-, c-, and d-bristles; medial surface with 1 cleaning bristle between a- and b-bristles and between b- and c-bristles, 5 cleaning bristles forming oblique row near base of c-bristle, 1 long spinous bristle with base just distal to d-bristle, and spines forming rows near ventral and dorsal margins; lateral side with no bristle between b- and c-bristles, and 1 long spinous bristle between c- and d-bristles. End joint with dorsal claw with proximal spines along ventral margin and distal spines along dorsal margin, and 5 spinous bristles.

Maxilla (Figure 63a): Epipodite with narrow spinous tip reaching midlength of dorsal margin of basale. Basale and endopodite with distribution of bristles similar to that of female.

Fifth Limb (Figure 63b): Lateral bristles of comb similar to those of female.

Sixth Limb (Figure 63c): Anterior margin of trunk of right limb with 4 small bristles dorsal to upper suture and 2 slender bristles (anterior slightly longer and stouter than other) just ventral to lower suture; anterior tip of skirt with 1 bristle. Anterior margin of trunk of left limb with 7 small bristles dorsal to upper suture and 2 bristles (anterior stouter and longer) just dorsal to lower suture; anterior tip of skirt without bristle. Both limbs with medial bristle in proximal anterior corner of trunk and 16 posteroventral bristles on skirt.

Seventh Limb (Figure 62f): Proximal group with 6 or 7 bristles (3 or 4 on each side); distal group with 6 bristles (3 on each side); each bristle with 2 or 3 bells. Terminus with opposing combs, each with 2 or 3 minute curved teeth.

Furca (Figure 63d): Right lamella with 8 claws, left with 9 (9th claw bent backwards); except for 9th claw of left lamella, all claws with posterior teeth; claw 1 of right lamella anterior to claw 1 of left.

Bellonci Organ and Medial Eye (Figure 62g): Similar to those of female. Lateral eyes absent.

Upper Lip (Figure 63e), Posterior of Body and Y-Sclerite (Figure 63d): Similar to those of female.

Genitalia (Figure 62h): Comprising 2 lobes: outer lobe with 3 small terminal bristles.

COMPARISONS.—The presence of 4 or more bristles dorsal to the upper suture on the anterior margin of the 6th limb separates S. hirpex from previously described species of the genus.