Vargula rapax Kornicker 1994

“Vargula rapax, new species

Figures 34-36

ETYMOLOGY.—From the Latin rapax (grasping, greedy).

HOLOTYPE.—Undissected ovigerous female in alcohol in the collection of the Victoria Museum.

TYPE LOCALITY.—Slope 48, 41°57.50’S, 148°37.90’E, Tasmania, off Freycinet Peninsula; depth 400 m.

PARATYPES.—Slope 48: USNM 194020, ovigerous female on slide and in alcohol; 4 undissected adult females and 2 juveniles in alcohol.

DISTRIBUTION.—Slope 48,400 m.

DESCRIPTION OF ADULT FEMALE.— Carapace oval in lateral view with well-defined concavity between dorsal end of short caudal process and edge of valve dorsal to process; incisur small at about midheight. Thin thread-like bristles sparsely distributed along inner side of anteroventral and ventral margins.

Infold: List of rostrum well defined; rostral infold with 9 bristles (mostly divided) in row dorsal to list and 6-8 bristles on or ventral to list; 1 longer bristle near midheight of rostrum and posterior to row of bristles (bristle on left but not right valve of USNM 194020); 2 bristles at inner end of rostrum and 1 smaller bristle dorsal to them. One fairly long divided bristle near valve edge just ventral to inner end of incisur. Narrow list with anterior end ventral to inner end of incisur continues along ventral margin, then broadens to form anterior edge of caudal process; row of about 40 short bristles along anteroventral list and anterior half of ventral list (bristles more closely spaced along anterior 1/4 of ventral infold); 4 bristles along posterior half of ventral list anterior to caudal process; anteroventral infold with 5 bristles between list and inner margin of infold; left valve with 2 bristles between list and outer edge of infold just anterior to ventral end of caudal process. Broad list along anterior edge of caudal process of left valve of USNM 194020 with row of 17 minute bristles emerging from pores, and about 10 on right valve. Posterior edge of caudal process with row of about 12 minute pores. Few minute pores between broad list and outer margin of infold, but whether these intersect surface of infold not resolved.

Selvage: Narrow lamellar prolongation with smooth outer edge along anterior margin of rostrum; prolongation absent along dorsal edge of incisur, wide and with striae along ventral edge of incisur, and narrow without striae at point near anterior end of incisur; prolongation narrow and with indistinct closely spaced striae along anteroventral and ventral margin of valve; selvage terminates at ventral end of caudal process; posterior edge of valve dorsal to caudal process without prolongation. On ventral margin of right valve proximal ridge of selvage located farther inward from outer edge than on left valve.

Carapace Size (length, height in mm): Slope 48: holotype, 3.02, 1.89, height 63% of length; USNM 194020, 3.04, 1.88, height 62% of length; 4 specimens without eggs: 3.08, 1.86, height 60% of length; 2.91, 1.88, height 65% of length; 2.94, 1.83, height 62% of length; 2.87, 1.82, height 63% of length. Length range 2.87-3.08 mm; height range 1.82-1.89.

First Antenna: 1st joint bare. 2nd joint spinous. 3rd joint with row of medial spines and 2 spinous bristles (1 ventral, 1 dorsal). 4th joint with ventral spines and 2 spinous bristles (1 ventral, 1 dorsal). Sensory bristle of 5th joint with 9 or 10 long stout proximal filaments, 2 slender distal filaments, and bifurcate tip. 6th joint with few small lateral spines, and medial bristle (with few indistinct spines) near dorsal margin. 7th joint: a-bristle spinous, about 1/3 longer than bristle of 6th joint; b-bristle about 1/3 longer than a-bristle, ringed proximal half with 3 short filaments; c-bristle about 1/3 longer than sensory bristle of 5th joint, with 9 filaments (some with spines) and bifurcate tip. 8th joint: d- and e-bristles about twice length of b-bristle, bare with blunt tips; f-bristle shorter man c -bristle, with 9 filaments (some with spines) and bifurcate tip; g-bristle slightly longer than c-bristle, with 10 filaments (some with spines) and bifurcate tip.

Second Antenna: Protopodite with distal medial bristle (with few indistinct spines) shorter than longest proximal bristle of 1st endopodial joint. Endopodite 3-jointed: 1st joint short, with 4 bare proximal bristles (1 long, 3 short) and 1 long distal bristle with indistinct spines; 2nd joint long, with bare distal bristle about same length as 3rd joint; 3rd joint long, about 70% length of 2nd joint, with long terminal filament about 1.4 times length of stem.

Exopodite: bristle of 2nd joint reaching 9th joint, with 9 ventral spines; bristles of joints 3-8 with natatory hairs, no spines; 9th joint with 3 bristles (2 long with natatory hairs, 1 short bare); joints 3-8 with basal spines increasing in length on distal joints; spine of 8th joint about 1/3 longer than 9th joint; lateral spine of 9th joint about twice length of joint; joints 2-8 with minute spines near distal margin.

Mandible: Coxale endite spinous with 2 stouter terminal spines with elongate peg between them; small bristle present at base of endite. Basale: ventral margin with 2 a-bristles (1 short with short spines, 1 longer with long proximal and short distal spines), 1 small bare lateral b-bristle, 2 c-bristles (proximal short bare, distal about twice length of long a-bristle, with short spines), and 2 spinous d-bristles (proximal slender with indistinct short spines, distal stout, very long, with long proximal and short distal spines); dorsal margin with 1 bristle (with short spines) near midlength, and 2 subterminal with short spines; medial surface with rows of spines; left but not right limb of USNM 194020 with long hairs in proximal ventral corner; lateral surface with row of spines near proximal 1/4 of dorsal margin (spines extend past edge of joint). Exopodite spinous, about same length as dorsal margin of 1st endopodial joint, with 2 subterminal bristles (distal about half length of proximal) with short spines. 1st endopodial joint with few terminal spines on dorsal margin, and 4 ventral bristles (1 long with long and short proximal spines and short distal spines, 1 long and 1 short with short spines, 1 minute bare). 2nd endopodial joint: ventral margin with 2 single ringed bare bristles and 2 terminal paired bare bristles; medial of terminal pair unringed (knife-like) slightly wider but about same length as lateral ringed bristle (dorsal margin with 18 spinous bristles (5 long, 1 medium (distal), and 12 short (spines on 1 short bristle stouter than spines on others)); medial surface and ventral margin spinous. 3rd endopodial joint with 3 stout spinous claws (dorsal claw slightly shorter) and 4 ringed bristles (long lateral ventral bristle slightly stouter in proximal part; long lateral dorsal bristle with short unringed knife-like tip).

Maxilla: Mounted endites of USNM 194020 somewhat obscured so that number of bristles approximate: endites I—III with 10, 5, and 6 (1 proximal (could be on basale), 5 terminal) bristles, respectively. Coxale with long plumose dorsal bristle. Basale with long slender ventral bristle and short medial bristle at midwidth. Exopodite well developed, hirsute, with 3 long bristles (proximal and outer of terminal bristles with long hairs; inner terminal bristle with short hairs). 1st endopodial joint with long medial and dorsal hairs, 2 alpha-bristles (longest with long hairs, other bare), 3 beta-bristles (outer longest pectinate, middle either bare or pectinate, inner shortest bare), and cutting tooth with single rounded cusp and proximal ventral hairs. 2nd endopodial joint with 4 ringed a-bristles (posterior 2 equally pectinate at midlength, others bare), 3 pectinate b-bristles, 3 c-bristles (1 small bare, others stout pectinate), and 3 pectinate d-bristles (posterior ringed, others unringed claw-like).

Fifth Limb: Endites I, II, and III each with 5 or 6 spinous bristles. Protopodial tooth well developed. 1st exopodial joint: main tooth with bare triangular proximal tooth and 6 pectinate teeth; bristle proximal to triangular tooth with long proximal spines; anterior side with row of 3 bristles (outer with long proximal spines and pectinate distally, others with long spines) and 1 long spinous bristle closer to protopodial tooth. 2nd exopodial joint with 4 unringed pectinate a-bristles, 3 ringed pectinate b'-bristles, 4 ringed pectinate b'-bristles, 1 c -bristle with long proximal and short distal spines, and 1 d-bristle with long spines. 3rd exopodial joint: inner lobe narrow, with indistinct long hairs and 3 bristles (proximal ringed, with long proximal and short distal spines; outer terminal unringed pectinate; inner terminal ringed, with short indistinct spines); outer lobe hirsute, with 2 ringed bristles (inner subterminal with short spines, outer terminal with long proximal and short distal spines). 4th exopodial joint separated from 5th by distinct suture, both joints hirsute; 4th joint with 3 or 4 ringed bristles with short spines; 5th joint with 2 ringed terminal bristles (with short spines) and small but distinct spines on sclerotized inner distal corner.

Sixth Limb: With 5 bare epipodial bristles (on both limbs of USNM 194020, proximal bristle with base on edge and bristle oriented dorsally; whereas, 4 distal bristles with bases medial and set back from edge, and bristles oriented ventrally). Endite I with 2 small, spinous, proximal, medial bristles and 1 long terminal bristle with long spines; endite II with 3 or 4 small, spinous, proximal, medial bristles and 2 long terminal bristles with long proximal and short distal spines; endite III with 1 spinous proximal medial bristle and 3 spinous terminal bristles (middle bristle short); endite IV with 1 spinous proximal medial bristle and 2 spinous terminal bristles. End joint with 6 or 7 bristles (with long proximal and short distal spines) followed by space, then 1 spinous bristle with long proximal and short distal spines and 2 plumose bristles. Endites III and IV and end joint with long medial hairs; end joint with stout lateral spines along ventral edge (spines absent in vicinity of 2 anterior and 2 posterior bristles). Limb with small amount of brown pigment.

Seventh Limb: With 21 bristles (distal group with 11 bristles (6 on comb side, 4 on peg side), each with 2-5 bells; proximal group with 11 bristles (5 on comb side, 6 on peg side), each with 3 bells. Comb with 13 teeth (4 short flat-tipped teeth on each side of 5 long alate teeth). Single spinous peg opposite comb.

Furca: Each lamella with 9 claws; claws 2 and 4 nonarticulated; claw 3 slenderer but about same length as claw 4; all claws with small teeth along posterior edge; claw 1 with fairly large medial row of teeth extending almost to tip; right lamella with few spines along anterior edge, and anterior to left lamella by width of base of claw 1.

Bellonci Organ: Elongate with small process at tip.

Eyes: Lateral eye large with 15 ommatidia and brown pigment between ommatidia. Medial eye smaller than lateral eye, with brown pigment, bare.

Upper Lip: Anterior unpaired part narrow ridge-like, with fairly large glandular openings. Tusks of paired part long with anterior proximal end terminating on ridge intersecting anterior edge of lip; each tusk with 3 widely separated glandular processes along posterior edge and 1 at tip, and few long indistinct hairs; in transmitted light brown pigment extending into tusks.

Genitalia: USNM 194020 with brownish oval (without spermatophore attached) on each side of body anterior to furca.

Anterior of Body: With projecting rounded anterior process just ventral to bases of 1st antennae.

Posterior of Body: Evenly rounded, bare.

Y-Sclerite: Typical for genus.

Number of Eggs: USNM 194020 with 26 eggs in marsupium, length of typical egg 0.38 mm, and many smaller unextruded eggs. Holotype with 8 eggs in marsupium, length of 1 egg 0.36 mm.

COMPARISONS.—The only other species of Vargula described previously herein having a large lateral eye is V. vix and V. trifax. The length of an adult female of V. vix is 1.74-1.84 mm compared to 2.87-3.08 mm for V. rapax. The furca of V. rapax has claws 2 and 4 nonarticulated, whereas all furcal claws of V. vix are articulated. The length range of the adult female V. trifax is 5.0-5.3 mm, and furcal claws 2,4, and 5 are nonarticulate. The female V. rapax is very close to the female V. subantarctica Komicker, 1975:171; they differ in that the carapaces of female V. rapax are more elongate than those of the female V. subantarctica (height 60%-65% of length for V. rapax (6 specimens), and 67%-73% of length for V. subantarctica (4 specimens)); also, the tusks of V. subantarctica have many more glandular openings. The carapace of V. puppis Poulsen, 1962:186, differs from that of V. rapax in having a much broader caudal process.”

(Kornicker, 1994, p.63-68)

Vargula rapax

ETYMOLOGY.—From the Latin rapax (grasping, greedy).

HOLOTYPE.—Undissected ovigerous female in alcohol in the collection of the Victoria Museum.

TYPE LOCALITY.—Slope 48, 41°57.50′S, 148°37.90′E, Tasmania, off Freycinet Peninsula; depth 400 m.

PARATYPES.—Slope 48: USNM 194020, ovigerous female on slide and in alcohol; 4 undissected adult females and 2 juveniles in alcohol.

DISTRIBUTION.—Slope 48,400 m.

DESCRIPTION OF ADULT FEMALE (Figures 34–36).—Carapace oval in lateral view with well-defined concavity between dorsal end of short caudal process and edge of valve dorsal to process (Figure 34a); incisur small at about midheight (Figure 34a,b). Thin thread-like bristles sparsely distributed along inner side of anteroventral and ventral margins (5 shown in Figure 34b).

Infold: List of rostrum well defined; rostral infold with 9 bristles (mostly divided) in row dorsal to list and 6–8 bristles on or ventral to list (Figure 34b); 1 longer bristle near midheight of rostrum and posterior to row of bristles (bristle on left but not right valve of USNM 194020) (Figure 34b); 2 bristles at inner end of rostrum and 1 smaller bristle dorsal to them. One fairly long divided bristle near valve edge just ventral to inner end of incisur. Narrow list with anterior end ventral to inner end of incisur continues along ventral margin, then broadens to form anterior edge of caudal process; row of about 40 short bristles along anteroventral list and anterior half of ventral list (bristles more closely spaced along anterior of ventral infold) (anterior 14 shown in Figure 34b); 4 bristles along posterior half of ventral list anterior to caudal process; anteroventral infold with 5 bristles between list and inner margin of infold (Figure 34b); left valve with 2 bristles between list and outer edge of infold just anterior to ventral end of caudal process. Broad list along anterior edge of caudal process of left valve of USNM 194020 with row of 17 minute bristles emerging from pores (15 shown in Figure 34c), and about 10 on right valve. Posterior edge of caudal process with row of about 12 minute pores (10 shown in Figure 34c). Few minute pores between broad list and outer margin of infold, but whether these intersect surface of infold not resolved (Figure 34c).

Selvage: Narrow lamellar prolongation with smooth outer edge along anterior margin of rostrum; prolongation absent along dorsal edge of incisur, wide and with striae along ventral edge of incisur, and narrow without striae at point near anterior end of incisur, prolongation narrow and with indistinct closely spaced striae along anteroventral and ventral margin of valve; selvage terminates at ventral end of caudal process; posterior edge of valve dorsal to caudal process without prolongation. On ventral margin of right valve proximal ridge of selvage located farther inward from outer edge than on left valve.

Carapace Size (length, height in mm): Slope 48: holotype, 3.02, 1.89, height 63% of length; USNM 194020, 3.04, 1.88, height 62% of length; 4 specimens without eggs: 3.08, 1.86, height 60% of length; 2.91, 1.88, height 65% of length; 2.94, 1.83, height 62% of length; 2.87, 1.82, height 63% of length. Length range 2.87–3.08 mm; height range 1.82–1.89.

First Antenna (Figure 34d): 1st joint bare. 2nd joint spinous. 3rd joint with row of medial spines and 2 spinous bristles (1 ventral, 1 dorsal). 4th joint with ventral spines and 2 spinous bristles (1 ventral, 1 dorsal). Sensory bristle of 5th joint with 9 or 10 long stout proximal filaments, 2 slender distal filaments, and bifurcate tip. 6th joint with few small lateral spines, and medial bristle (with few indistinct spines) near dorsal margin. 7th joint: a-bristle spinous, about longer than a-bristle of 6th joint; b-bristle about longer than a-bristle, ringed proximal half with 3 short filaments; c-bristle about longer than sensory bristle of 5th joint, with 9 filaments (some with spines) and bifurcate tip. 8th joint: d- and e-bristles about twice length of b-bristle, bare with blunt tips; f-bristle shorter than c-bristle, with 9 filaments (some with spines) and bifurcate tip; g-bristle slightly longer than c-bristle, with 10 filaments (some with spines) and bifurcate tip. (Not all bristles of 7th and 8th joints shown in Figure 34d

Second Antenna: Protopodite with distal medial bristle (with few indistinct spines) shorter than longest proximal bristle of 1st endopodial joint (Figure 34e), Endopodite 3-jointed (Figure 34e): 1st joint short, with 4 bare proximal bristles (1 long, 3 short) and 1 long distal bristle with indistinct spines; 2nd joint long, with bare distal bristle about same length as 3rd joint; 3rd joint long, about 70% length of 2nd joint, with long terminal filament about 1.4 times length of stem. Exopodite: bristle of 2nd joint reaching 9th joint, with 9 ventral spines; bristles of joints 3–8 with natatory hairs, no spines; 9th joint with 3 bristles (2 long with natatory hairs, 1 short bare); joints 3–8 with basal spines increasing in length on distal joints; spine of 8th joint about longer than 9th joint (Figure 34f; lateral spine of 9th joint about twice length of joint; joints 2–8 with minute spines near distal margin.

Mandible (Figure 34g–i): Coxale endite spinous with 2 stouter terminal spines with elongate peg between them; small bristle present at base of endite (Figure 34h). Basale: ventral margin with 2 a-bristles (1 short with short spines, 1 longer with long proximal and short distal spines) (Figure 34g,h), 1 small bare lateral b-bristle, 2 c-bristles (proximal short bare, distal about twice length of long a-bristle, with short spines), and 2 spinous d-bristles (proximal slender with indistinct short spines, distal stout, very long, with long proximal and short distal spines); dorsal margin with 1 bristle (with short spines) near midlength, and 2 subterminal with short spines; medial surface with rows of spines; left but not right limb of USNM 194020 with long hairs in proximal ventral corner (Figure 34h); lateral surface with row of spines near proximal of dorsal margin (spines extend past edge of joint (Figure 34g)). Exopodite spinous, about same length as dorsal margin of 1st endopodial joint, with 2 subterminal bristles (distal about half length of proximal) with short spines. 1st endopodial joint with few terminal spines on dorsal margin, and 4 ventral bristles (1 long with long and short proximal spines and short distal spines, 1 long and 1 short with short spines, 1 minute bare). 2nd endopodial joint: ventral margin with 2 single ringed bare bristles and 2 terminal paired bare bristles; medial of terminal pair unringed (knife-like) slightly wider but about same length as lateral ringed bristle (Figure 34i); dorsal margin with 18 spinous bristles (5 long, 1 medium (distal), and 12 short (spines on 1 short bristle stouter than spines on others)) (not all bristles shown in Figure 34g); medial surface and ventral margin spinous. 3rd endopodial joint with 3 stout spinous claws (dorsal claw slightly shorter) and 4 ringed bristles (long lateral ventral bristle slightly stouter in proximal part (Figure 34i); long lateral dorsal bristle with short unringed knife-like tip).

Maxilla: Mounted endites of USNM 194020 somewhat obscured so that number of bristles approximate: endites I–III with 10, 5, and 6 (1 proximal (could be on basale), 5 terminal) bristles, respectively (Figure 35a). Coxale with long plumose dorsal bristle (Figure 35c). Basale with long slender ventral bristle and short medial bristle at midwidth (Figure 35c). Exopodite well developed, hirsute, with 3 long bristles (proximal and outer of terminal bristles with long hairs; inner terminal bristle with short hairs) (Figure 35b,c). 1st endopodial joint with long medial and dorsal hairs, 2 alpha-bristles (longest with long hairs, other bare), 3 beta-bristles (outer longest pectinate, middle either bare or pectinate, inner shortest bare), and cutting tooth with single rounded cusp and proximal ventral hairs (Figure 35b–d). 2nd endopodial joint with 4 ringed a-bristles (posterior 2 equally pectinate at midlength, others bare) (Figure 35b), 3 pectinate b-bristles, 3 c-bristles (1 small bare, others stout pectinate), and 3 pectinate d-bristles (posterior ringed, others unringed claw-like) (Figure 35d).

Fifth Limb: Endites I, II, and III each with 5 or 6 spinous bristles. Protopodial tooth well developed (Figure 35e). 1st exopodial joint: main tooth with bare triangular proximal tooth and 6 pectinate teeth (Figure 35f); bristle proximal to triangular tooth with long proximal spines; anterior side with row of 3 bristles (outer with long proximal spines and pectinate distally, others with long spines) and 1 long spinous bristle closer to protopodial tooth (Figure 35e). 2nd exopodial joint with 4 unringed pectinate a-bristles, 3 ringed pectinate b′-bristles, 4 ringed pectinate b′-bristles (not shown), 1 c-bristle with long proximal and short distal spines, and 1 d-bristle with long spines (Figure 35e,f). 3rd exopodial joint: inner lobe narrow, with indistinct long hairs and 3 bristles (proximal ringed, with long proximal and short distal spines; outer terminal unringed pectinate; inner terminal ringed, with short indistinct spines) (Figure 35e); outer lobe hirsute, with 2 ringed bristles (inner subterminal with short spines, outer terminal with long proximal and short distal spines). 4th exopodial joint separated from 5th by distinct suture, both joints hirsute; 4th joint with 3 or 4 ringed bristles with short spines; 5th joint with 2 ringed terminal bristles (with short spines) and small but distinct spines on sclerotized inner distal corner (Figure 35e).

Sixth Limb (Figure 36a): With 5 bare epipodial bristles (on both limbs of USNM 194020, proximal bristle with base on edge and bristle oriented dorsally; whereas, 4 distal bristles with bases medial and set back from edge, and bristles oriented ventrally). Endite I with 2 small, spinous, proximal, medial bristles and 1 long terminal bristle with long spines; endite II with 3 or 4 small, spinous, proximal, medial bristles and 2 long terminal bristles with long proximal and short distal spines; endite III with 1 spinous proximal medial bristle and 3 spinous terminal bristles (middle bristle short); endite IV with 1 spinous proximal medial bristle and 2 spinous terminal bristles. End joint with 6 or 7 bristles (with long proximal and short distal spines) followed by space, then 1 spinous bristle with long proximal and short distal spines and 2 plumose bristles. Endites III and IV and end joint with long medial hairs; end joint with stout lateral spines along ventral edge (spines absent in vicinity of 2 anterior and 2 posterior bristles). Limb with small amount of brown pigment (not shown).

Seventh Limb (Figure 36b,c): With 21 bristles (distal group with 11 bristles (6 on comb side, 4 on peg side), each with 2–5 bells; proximal group with 11 bristles (5 on comb side, 6 on peg side), each with 3 bells. Comb with 13 teeth (4 short flat-tipped teeth on each side of 5 long alate teeth). Single spinous peg opposite comb (Figure 36c).

Furca (Figure 35g): Each lamella with 9 claws; claws 2 and 4 nonarticulated; claw 3 slenderer but about same length as claw 4; all claws with small teeth along posterior edge (not shown); claw 1 with fairly large medial row of teeth extending almost to tip (not shown); right lamella with few spines along anterior edge, and anterior to left lamella by width of base of claw 1.

Bellonci Organ (Figure 34j,k): Elongate with small process at tip.

Eyes: Lateral eye large with 15 ommatidia and brown pigment between ommatidia (Figure 34a,j,l). Medial eye smaller than lateral eye, with brown pigment, bare (Figure 34j,k).

Upper Lip (Figures 34j, 36d): Anterior unpaired part narrow ridge-like, with fairly large glandular openings. Tusks of paired part long with anterior proximal end terminating on ridge intersecting anterior edge of lip; each tusk with 3 widely separated glandular processes along posterior edge and 1 at tip, and few long indistinct hairs; in transmitted light brown pigment extending into tusks (stippled in Figure 36d).

Genitalia (Figure 36e): USNM 194020 with brownish oval (without spermatophore attached) on each side of body anterior to furca.

Anterior of Body (Figure 34j): With projecting rounded anterior process just ventral to bases of 1st antennae.

Posterior of Body (Figure 36e): Evenly rounded, bare.

Y-Sclerite (Figure 36e): Typical for genus.

Number of Eggs: USNM 194020 with 26 eggs in marsupium, length of typical egg 0.38 mm (1 shown within carapace in Figure 34a), and many smaller unextruded eggs (Figure 36e). Holotype with 8 eggs in marsupium, length of 1 egg 0.36 mm.

COMPARISONS.—The only other species of Vargula described previously herein having a large lateral eye is V. vix and V. trifax. The length of an adult female of V. vix is 1.74–1.84 mm compared to 2.87–3.08 mm for V. rapax. The furca of V. rapax has claws 2 and 4 nonarticulated, whereas all furcal claws of V. vix are articulated. The length range of the adult female V. trifax is 5.0–5.3 mm, and furcal claws 2, 4, and 5 are nonarticulate. The female V. rapax is very close to the female V. subantarctica Kornicker, 1975:171; they differ in that the carapaces of female V. rapax are more elongate than those of the female V. subantarctica (height 60%–65% of length for V. rapax (6 specimens), and 67%–73% of length for V. subantarctica (4 specimens)); also, the tusks of V. subantarctica have many more glandular openings. The carapace of V. puppis Poulsen, 1962:186, differs from that of V. rapax in having a much broader caudal process.