Xenoleberis bex Kornicker 1994

Xenoleberis bex

ETYMOLOGY.—From the Greek bex (cough).

HOLOTYPE.—Ovigerous female on slide and in alcohol in collection of the Museum of Victoria.

TYPE LOCALITY.—Slope 39, 38°19.10′S, 149°14.30′E, Victoria, S of Point Hicks; depth 600 m.

PARATYPES.—None.

DISTRIBUTION.—Slope 39, 600 m.

DESCRIPTION OF ADULT FEMALE (Figures 101–103).—Carapace elongate with slightly convex ventral and dorsal margins (Figure 101a,b). Right valve with ventral and posterior edges set inward from valve margins (Figure 101b,e). Left valve with only middle part of ventral edge set slightly inward from valve margin.

Infold: Ventral infold with narrow ridge having anterior end near anteroventral corner and posterior end near posteroventral corner (Figure 101b,c,e); the ridge with wider space between it and valve margin on right valve than on left valve; a row of distinct pores between ridge and valve edge (Figure 101c,e). Narrow list with anterior end just ventral to inner end of incisur continues along ventral infold close to inner margin of infold, then broadens along posteroventral and posterior infold (Figure 101b,c,e). Rostral infold dorsal to list with row of about 50 long bristles just within outer edge, about 5 additional long bristles near tip, and many minute bristles; rostral infold between list and incisur with about 35 long bristles (Figure 101d); anteroventral infold with row of about 20 long bristles near outer edge and many minute bristles proximal to row; about 20 additional long bristles along anterior third of ventral margin, and about 20 widely spaced bristles along middle part of ventral margin; infold between broad posteroventral-posterior list and valve edge with about 65 bristles (ventral 30 longer); about 15 long bristles in row anterior to ventral end of broad posteroventral list. Broad posteroventral-posterior list with 22–24 transparent flap-like bristles and 51–53 slender bristles (2–4 (mostly 2) slender bristles between each pair of flap-like bristles). Infold posterior to broad posterior list with 4 indistinct round tubular processes (4 small circles in Figure 101e); several minute pustules in vicinity of tubular processes. A row of small bristles (possibly pores and not bristles) just within posterior edge of valve dorsal to end of narrow ridge (Figure 100e). Right valve with dense row of long hairs between dorsal end of broad posterior list and valve edge (hairs probably represent selvage) (Figure 101e).

Selvage: Fringed lamellar prolongation along ventral edge of incisur.

Central Adductor Muscle Attachments (Figure 101f): About 13 ovoid attachments.

Carapace Size (length, height in mm): Holotype, 213, 1.03, height 48% of length.

First Antenna (Figure 101h,g): First joint with medial and lateral spines. 2nd joint with few ventral spines and 1 spinous dorsal bristle. 3rd joint without suture separating it from 4th joint except near ventral edge; 3rd plus 4th joints quadrate. 3rd joint with small ventral bristle and 6 dorsal bristles (2 single with long proximal and short distal spines followed by 2 lateral bristles with short spines and 2 medial bristles with long proximal and short distal spines (Figure 101g). 4th joint with few dorsal and lateral spines, 2 ventral bristles with short spines, and 1 long dorsal bristle with short spines. 5th joint with lateral row of short spines in distal dorsal comer; sensory bristle with short stout stem, 1 short slender proximal filament, and 6 stout terminal filaments (2 distal filaments not fused at proximal end). 6th joint with lateral row of short spines in distal dorsal corner, long terminal hairs along dorsal part of distal edge (hairs on both lateral and medial sides), and 1 long medial bristle (with few short spines) near ventral margin (bristle not shown). 7th joint: a-bristle claw-like, short, with small lateral teeth; stout b-bristle about longer than a-bristle, with 4 marginal filaments (filaments and stem with minute terminal process); c-bristle about twice length of b-bristle, with 9 or 10 marginal filaments (8 or 9 proximal, 1 distal) (filaments and stem with minute terminal process). 8th joint: d-bristle more than half length of e-bristle, unringed, bristle-like (tapering to point) with minute marginal spines; e-bristle about twice length of a-bristle, with narrowly spaced indistinct rings, filament-like (with parallel sides) with blunt tip; minute lateral pore near base of d- and e-bristles; f-bristle about length of c-bristle, bent dorsally, with 4 spinous proximal filaments and 1 bare distal filament (filaments and stem with minute terminal process); g-bristle about same length as c-bristle, with 7 filaments (6 proximal, 1 distal) (filaments and stem with minute terminal process) (g-bristle not shown).

Second Antenna (Figure 102a): Protopodite with rows of medial spines near dorsal margin and small distal medial bristle. Endopodite distinctly 3-jointed with long subterminal filament. Exopodite: 1st joint bare; bristle of 2nd joint reaching 7th or 8th joints, with abundant slender ventral spines; long bristles of joints 3 and 4 or 3–6 with proximal ventral spines and distal natatory hairs; long bristles of joints 5–8 or 7 and 8 with natatory hairs, no spines; 9th joint with 3 bristles (2 long with natatory hairs, 1 short (dorsal) bare); joints 3–8 each with small basal spine (spine of 8th joint about length of 9th joint); 9th joint with small lateral spine about – length of joint; joints 2–8 with row of spines along distal edge (some spines (near dorsal edge) of 3rd joint longer than on other joints).

Mandible: Coxale endite (Figure 102b): ventral branch with spines forming 4 oblique rows and tip with 2 spines; small bristle near base of branch; dorsal branch with 3 small double teeth pointing distally followed by 1 small double perpendicular tooth, 1 elongate recurved tooth with few small spines, and long main spine with long slender spines along concave edge; tip of branch prolonged as slender hair-like spine with long proximal marginal hairs that are also on distal end of ventral edge of tip; posterior bristle represented by small stump bearing marginal spines; spines also present on dorsal edge of endite adjacent to stump; dorsal edge of endite at about length serrate. Basale endite (Figure 102c): with 3 spinous end bristles (illustrated endite of left limb of holotype with 1 bristle represented by stump), 3 triaenid bristles with 3 or 4 pairs of spines excluding terminal pair, 2 equilength dwarf bristles, glandular peg, and 1 minute spine or bristle near proximal ventral end (latter possibly on basale rather than endite). Basale (Figure 102c,d): ventral margin with narrow U-shaped depression near endite (Figure 102c); dorsal margin with indistinct distal spines, 1 backward oriented spinous bristle near midlength, and 2 subequal spinous terminal bristles (Figure 102d). Exopodite about length of dorsal margin of 1st endopodial joint, hirsute, with 2 small spinous subterminal bristles (Figure 102d). 1st endopodial joint with 3 long spinous ventral bristles (not shown). 2nd endopodial joint (Figure 102e): ventral margin with 3 terminal bristles with short spines; dorsal margin with 3 small indistinct spines proximal to short spinous proximal bristle, stout spinous a-, b-, c-, and d-bristles (c-bristle slightly stouter than others and with stouter and more closely spaced marginal spines); medial surface with rows of minute spines, 1 short spinous cleaning bristle between a- and b-bristles and between b- and c-bristles (both almost on ventral edge), 5 spinous cleaning bristles forming oblique row adjacent to c-bristle (outer of these fairly stout), and long spinous g-bristle adjacent to distal edge of base of c-bristle; lateral surface without e-bristle between b- and c-bristles, and with long spinous f-bristle between c- and d-bristles (all bristles ringed, but rings shown only on f- and g-bristles). 3rd endopodial joint with fairly short, straight, bare, dorsal claw and 5 ringed bristles (4 long stout, 1 short slender medial, all with short spines; rings shown only on short medial bristle) (Figure 102e).

Maxilla (Figure 103a,b): Epipodite fairly short with hirsute tip not reaching midlength of dorsal margin of basale (Figure 103a). Endite I with 4 bristles (3 long spinous, 1 short bare); endite II with long hairs and 3 hirsute bristles (distal shorter) (Figure 103b). Basale: medial surface with 2 proximal bristles near dorsal margin; lateral surface with 1 proximal and 1 distal bristle near ventral margin; ventral margin with backward oriented proximal bristle and long spinous terminal bristle. 1st endopodial joint with short bare alpha-bristle and long bare beta-bristle. 2nd endopodial joint with long terminal bristle (with indistinct spines) reaching just past beta-bristle of 1 st joint.

Fifth Limb (Figure 103c): Comb with short medial hairs along ventral edge, long distal dorsal hairs, stout spinous exopodial bristle reaching past distal end, 2 small slender lateral bristles just ventral to base of stout bristle, 2 fairly widely separated pairs of lateral bristles close to ventral edge near midlength, 3 spinous lateral bristles (1 proximal, 2 distal) with bases almost on ventral edge, and 36 spinous bristles along ventral edge, each with short bare subterminal bulbous part (detail in Figure 103c).

Sixth Limb (Figure 103d,e): Minute proximal medial bristle just anterior to trunk midwidth (Figure 103d,e); anterior margin with single endite suture with bare bristle; a 2nd bare bristle present between endite and anterior end of limb probably also endite bristle but usual endite suture absent (Figure 103e); anteroventral corner of skirt with 4 or 5 spinous bristles (2nd bristle from anterior tip stouter and longer than others); lateral flap with long hairs but no bristles; ventral and posteroventral margin of skirt with total of about 19 spinous bristles (those at posterior corner longer) (Figure 103d).

Seventh Limb (Figure 103f): Each limb with 14 bristles: 8 proximal (4 on each side), 6 distal (3 on each side), each bristle with 3–5 bells. Terminus with opposing combs each with 11 or 12 spinous teeth.

Furca (Figure 101 i): Each lamella with 10 claws; posterior 1 or 2 claws bristle-like.

Bellonci Organ (Figures 102f, 103g): Elongate, broader and with suture or wrinkle at midlength, then tapering to broadly rounded tip.

Eyes: Lateral eyes absent. Medial eye unpigmented, bare (Figure 103g).

Lips (Figure 102f): Upper lip a hirsute lobe (without spines) on each side of bare saddle. Lower lip a hirsute flap on each side of mouth.

Genitalia: Sclerotized ring on each side of body anterior to furca.

Posterior of Body: Obscured by gills but probably without thumb-like dorsal process.

Y-Sclerite: Typical for subfamily.

Gills: Well developed.

Number of Eggs: Holotype with 13 eggs in marsupium, length of typical egg 0.38 mm. Location of 1 egg shown in Figure 101a.

COMPARISONS.—Xenoleberis bex differs from other species in the genus in lacking lateral eyes. The carapace is without the melanophores of X. yamadai.

CYCLASTEROPINAE Poulsen, 1965

The Cyclasteropinae include 3 tribes: Cyclasteropini Poulsen, 1965, Cycloleberidini Hartmann, 1974, and Tetraleberidini Kornicker, 1981 (Kornicker, 1981c:72). All have been reported from the vicinity of Australia (Kornicker, 1981c: 18) but only the Cycloleberidini are represented in the present collection.

CYCLOLEBERIDINI Hartmann, 1974

Only the genus Leuroleberis is represented in the collection.

Leuroleberis Kornicker, 1981

TYPE SPECIES.—Leuroleberis sharpei Kornicker, 1981:97.

COMPOSITION.—Only 1 species, L. mackenziei Kornicker, 1981, is known from the vicinity of Australia.