Chelicopia fax Kornicker ex Kornicker & Thomassin 1998

Chelicopia fax

ETYMOLOGY.—From the Latin fax (torch, firebrand).

HOLOTYPE.—Adult female on slide and in alcohol.

TYPE LOCALITY.—BT-615.

PARATYPES.—None.

DISTRIBUTION.—Collected only at type locality; depth 8 m.

DESCRIPTION OF ADULT FEMALE (Figures 70–72).—Carapace oval in lateral view with slight flattening of posterodorsal margin (Figure 70). Projecting caudal process absent but posteroventral corner of valve edge flat when viewed medially (Figure 71a): valve margin in caudal area also marked by long slender bristles more numerous than elsewhere (Figure 70). Anterior edge of valve evenly rounded, except for minute indentation in margin at midheight (Figure 70).

Ornamentation:Carapace with abundant small thumb-like structures with hollow axis (shown as minute pustules in Figure 70); because of hollow axis, structures appear ring-like except along valve margins where they appear thumb-like; structures slightly longer in vicinity of caudal process (Figure 71a). Surface of valves without gel-like coating.

Surface Bristles: Short and long bristles (some with broad base) present along valve margins, sparse elsewhere; abundant long pointed bristles form row posterior to caudal area (Figure 70; not all bristles shown in Figure 71a); surface of valves between thumb-like processes with minute spines (few shown near top of Figure 71a).

Infold: Broad infold along anterior and ventral margins, and in caudal area. Anterior infold with small bristle near midheight. Infold of caudal area with row of 10 or 11 small bristles at midwidth, 3 longer bristles along inner edge, and 2 backward-pointing spine-like bristles along posterior edge (Figure 71a); 2 setal bristles present on infold just dorsal to caudal area (Figure 71a). Posterior edge of infold of caudal area overhangs outer surface of valve (inner edge of overhang indicated by dashed line in Figure 71a).

Carapace Size (length, height in mm): Holotype, 1.00, 0.72.

First Antenna (Figure 71b): 1st joint bare. 2nd joint with few dorsal spines and 1 spinous dorsal bristle. 3rd joint fused to 4th, with 2 long bristles (1 ventral, 1 dorsal). 4th joint with 3 long bristles (2 spinous ventral, 1 bare dorsal). Sensory bristle of long 5th joint with 2 minute spine-like filaments and terminal spine. 6th joint fused to 5th, with short bare medial bristle. 7th joint: a-bristle about twice length of bristle of 6th joint, bare; b-bristle slightly shorter than a-bristle, with terminal spine; c-bristle longer than bristle of 5th joint, with 3 minute filaments and terminal spine. 8th joint: d- and e-bristles shorter than bristle of 5th joint, bare with blunt tips (d-bristle shorter than e-bristle); f-bristle shorter than bristle of 5th joint, with minute marginal filament and terminal spine; g-bristle about same length as bristle of 5th joint, with 3 small filaments (1 proximal, 2 near midlength) and terminal spine.

Second Antenna: Protopodite bare. Endopodite 1-jointed with small proximal anterior bristle, medial spines, and small terminal bulge (Figure 71c). Exopodite: 1st joint with minute curved tubular medial bristle on terminal margin; bristle of 2nd joint long, with ventral spines (spines stout proximally and becoming slenderer distally along bristle) and few natatory hairs near tip; bristles of joints 3–8 with stout proximal ventral spines and distal natatory hairs; 9th joint with 2 bristles (ventral bristle shorter and slenderer than bristle of 8th joint, with slender ventral spines and distal natatory hairs; dorsal bristle short and slender with few short hairs); joints 2–7 with few small spines along distal margin.

Mandible (Figure 72a,b): Coxale endite consisting of stout spine with long proximal spines and indistinct short distal teeth. Coxale with many medial spines near endite and spines along ventral margin. Basale: dorsal margin with 1 minute bristle near midlength and 2 subterminal bristles (longer with indistinct marginal hairs, other small, lateral, bare); ventral margin with 5 short bristles (3 proximal, 2 distal) with bases on medial side, and 1 short bristle with base on lateral side. Exopodite, if present, obscured. 1st endopodial joint: medial surface with spines forming distal crescentic row, spines along distal margin in dorsal corner, spines near distal dorsal margin, and 2 spines (proximal stouter and with socket) near base of terminal ventral claw; lateral surface with rows of distal spines (not shown); dorsal margin with subterminal and terminal spines forming part of rows continuing on medial and lateral surfaces of joint; ventral margin with stout terminal claw with 2 proximal ventral prongs (distal stouter and longer) and 3 small proximal dorsal prongs. 2nd endopodial joint: medial and lateral surfaces with rows of spines near midlength, along distal edge, and distally along dorsal edge; dorsal margin with 3 stouter spines near midlength (1 with base on margin, and 2 with bases on lateral side (1 of these fairly long)); ventral margin with stout terminal claw longer than claw of 1st joint. 3rd endopodial joint with stout terminal claw (stouter than claw of 2nd joint), and 2 small spine-like bristles (1 ventral, 1 dorsal).

Maxilla: Precoxale with dorsal fringe of long hairs (Figure 72d). Coxale with short bare dorsal bristle. Endite I with 6 bristles (3 stout unringed pectinate, others ringed spinous) (Figure 72c), endite II with proximal spines and 4 bristles (2 stout unringed pectinate, others ringed); endite III with 6 bristles (1 stout unringed pectinate, others ringed or partly ringed, some spinous). Basale with 1 short bare bristle near exopodite. Exopodite with 2 long bristles (Figure 72d). Endopodite: 1st joint with slender spinous alpha- and beta- bristles with distal rings; 2nd joint with 2 slender a-bristles (posterior bristle longer), 1 slender c-bristle, and 5 stout pectinate terminal bristles.

Fifth Limb (Figure 72e): Single endite with short bare bristle. 1st exopodial joint with 2 spinous bristles. Exopodial joints 2–5 not well defined from each other: joint 2 with 4 bristles (3 long, 1 short); inner lobe of 3rd joint with 3 bristles (2 long, 1 short (latter could be on 4th joint)); outer lobe of 3rd joint with short bristle; 4th plus 5th joints with 2 long bristles; 2nd and 3rd joints hirsute; all bristles ringed distally (not shown).

Sixth Limb (Figure 72f): Endite I with 3 bristles (2 short, 1 longer); endite II with 5 long spinous bristles. End joint with 9 or 10 bristles (2 posterior bristles fairly short and with short spines similar to those of other bristles). Limb without hairs.

Seventh Limb (Figure 72g): Proximal group with 4 bristles (2 on each side), each with 3 or 4 bells. Terminal group with 6 bristles (3 on each side), each with 2–5 bells; bristles bare or with few distal indistinct spines. Terminus with comb comprising 7–9 curved teeth opposite comb with 2 curved teeth.

Furca (Figure 71d): Each lamella with 6 claws: claws 1, 2, and 4 stout, primary, nonarticulated, and with narrowly rounded tips; claws 3, 5, and 6 short slender secondary with pointed tips. Claws 1, 2, and 4 with 2 rows of teeth along posterior edges (not shown); claws 2, 5, and 6 with single row; claws 1–5 with slender spines or hairs along anterior edges (not shown). Lamellae with single spine following claw 6; anterior margin of right lamella dorsal to claw 1 with abundant long hairs. Right lamella anterior to left by width of base of claw 1. A broad “apron” extending anteriorly just proximal to lamellae (not shown).

Bellonci Organ (Figure 72h): Elongate with 3 indistinct sutures near midlength; tip broadly rounded.

Eyes: Medial eye bare with narrow area of light brown pigment (Figure 72h,i). Lateral eye slightly smaller than medial eye, with trace of brown pigment and 5 amber-colored ommatidia (Figure 72i).

Upper Lip (Figure 71e): Broadly rounded.

Genitalia (Figure 72j): Ovoid disk (without spermatophore) on each side of body anterior to furca.

Anterior of Body (Figure 71e): Broadly rounded ventral to 1st antenna.

Posterior of Body: Evenly rounded, bare.

Y-Sclerite (Figure 72j): Typical for subfamily.

COMPARISONS.—The carapace of C. fax is similar to that of C. radix, except for the absence of digitate “skirts” on the abundant small ring-like structures on the outer surface. The 1st endopodial joint of the mandible of C. fax differs from that of C. radix in having two rather than one stout prong on the ventral margin of the long terminal claw, and in the absence of a short ventral bristle at joint midlength. (Chelicopia radix is known only from late juveniles.)

Eurypylus Brady, 1869

TYPE SPECIES.—Eurypylus petrosus Brady, 1869.

COMPOSITION AND DISTRIBUTION.—Including a new species described herein the genus includes seven species of which two (E. chavturi Kornicker, 1992 and E. matrix, new species), were collected in the western Indian Ocean.