“Harbansus vatrax, new species
Figures 11-14
ETYMOLOGY. – From the Latin vatrax (crooked feet).
HOLOTYPE.—Undissected ovigerous female in alcohol in the collection of the Museum of Victoria.
TYPE LOCALITY.—Slope 1, 34°59.52'S, 151°5.94'E, New South Wales, off Nowra, depth 204 m.
PARATYPES.—Slope 1: USNM 193923, 1 adult female on slide and in alcohol; USNM 193924, 1 adult male on slide and alcohol; 1 dissected instar III male in alcohol; 26 adult females and juveniles in alcohol.
DISTRIBUTION.—Slope 1, 204 m.
DESCRIPTION OF ADULT FEMALE.— Carapace elongate with prominant rostrum and broad projecting caudal process; tip of rostrum and anteroventral and ventral margins with lateral overlap. Shape of carapace unusual in being triangular in anterior and posterior views (broad near ventral base and narrower dorsally) (body inside shell also broad near base and narrower near apex). Hinge straight and depressed.
Ornamentation: Lateral rib extends from rostrum to caudal process; rib actually widest part of valve from which surface slopes to ventral and dorsal margins of valve. Valve surface including rib with abundant well defined small fossae.
Infold: Rostral infold with row of 4 spinous bristles, and a pair of bristles at inner end of incisor; anteroventral infold with 1 bristle near incisor and about 10 narrow ridges. Infold of caudal process with 6 frond-like bristles along ridge forming “pocket” (left valve of USNM 193923 with additional frond-like bristle near dorsal edge of infold near inner margin anterior to caudal process.
Selvage: Narrow along straight distal edge of rostrum, broad and divided at inner end of incisor, broad with fringe along ventral edge of valve, absent along posterior edge of caudal process, and narrow along posterior edge of valve dorsal to caudal process.
Central Adductor Muscle Attachments: Located in lateral rib at anterior 73 of valve; 3 nonadductor stout muscles attached to shell at about 1/3 height from dorsal end of valve and about 1/3 length from posterior end (these terminate anteriorly near base of 1st antenna).
Carapace Size (length, height in mm): Slope 1: holotype, 1.52, 0.83; USNM 193923, 1.53, 0.84 (maximum width 0.87 mm); USNM 193925, 1.56, 0.88; 1.54, 0.82; 1.56, 0.83; 1.57, 0.86; 1.56, 0.89.
First Antenna: 1st joint bare. 2nd joint with ventral spines and 1 dorsal bristle (with long proximal spines) at distal 2/3. 3rd joint short with 3 bristles (1 ventral, 2 dorsal). 4th joint with ventral spines and 3 bristles (2 ventral, 1 dorsal). Sensory bristle of 5th joint with 2 short proximal filaments and 3 distal filaments (1 short, 2 long) excluding stem. Medial bristle of 6th joint about 3A length of 5th joint. 7th joint: a-bristle about 3 times length of bristle of 6th joint; b-bristle about 3A length of sensory bristle of 5th joint, with 1 short filament at midlength and 2 spines or papillae at tip; c-bristle about same length as sensory bristle, with 5 filaments excluding stem and 2 minute papillae at tip. 8th joint: d- and e-bristles about same length as c-bristle, bare with blunt tips; f-bristle about same length as c-bristle, with 2 short proximal filaments and 3 distal filaments (1 short, 2 long) excluding stem; g-bristle similar to f-bristle.
Second Antenna: Protopodite bare. Endopodite 2-jointed: 1st joint with 2 small ventral bristles; 2nd joint elongate with long ventral bristle (with or without spines) at midlength and short terminal bristle about 1 to 1 1/2 times width of joint at midlength. Exopodite: 1st joint with or without minute medial terminal bristle; bristles of joints 2-8 with stout ventral spines on proximal 2/3 to 3/4 and natatory hairs on thinner distal 1/4 to 1/3 (hairs may be absent on some bristles); 9th joint narrow, with 2 bristles; joints 5-7 with small basal spines. Right limb of USNM 193923 aberrant in having only 7 joints.
Mandible: Coxale endite hirsute and spinous, with small unringed bristle near base. Basale: dorsal margin with 3 bristles (1 near midlength, 2 terminal); ventral margin with 1 terminal bristle with long spines; medial surface spinous, with 4 bristles near ventral margin (3 proximal, 1 distal); lateral side with 2 bristles (with long spines) near ventral margin. Exopodite slender, about 3A length of dorsal margin of 1st endopodial joint, hirsute in distal half, with 2 subterminal bristles (lateral and proximal of these longer, spinous). 1st endopodial joint with medial spines and 3 ventral bristles (2 long with long spines, 1 short with indistinct short spines); dorsal margin with small terminal spines. 2nd endopodial joint: dorsal margin with 2 or 3 long bristles near midlength; ventral margin with 4 bristles forming 2 distal groups (2 bristles in each group); usual medial spines not observed. 3rd endopodial joint with 2 stout claws, 1 minute dorsal claw (absent on right limb of USNM 193923 but present on left limb, and on both limbs of USNM 193925) and 3 slender ringed bristles.
Maxilla: Precoxale and coxale with dorsal fringe of long hairs; coxale with long, stout, plumose, dorsal bristle. Endite I wider than endites II and III, with 6 bristles; endite II also with 6 bristles; endite III with 1 proximal lateral bristle and 7 distal bristles. Basale with 3 long bristles along distal margin (2 ventral, 1 dorsal). Exopodite small with 3 bristles (2 long, 1 short). Endopodite: 1st joint with 1 alpha-bristle with long spines and 2 beta-bristles (outer longer and with long spines, other without long spines); 2nd joint with 9 claws and bristles.
Fifth Limb: Epipodite with 41 bristles. Endite I with 2 bristles (1 long with long hairs, 1 short with short spines); endite II with 3 bristles; endite III with about 8 bristles. 1st exopodial joint: main tooth with proximal bristle, 1 smooth tooth followed by 3 pectinate teeth and 1 smooth tooth anterior to distal pectinate tooth; anterior side with 2 bristles along distal edge proximal to main tooth. 2nd exopodal joint with large square tooth with 2 minute teeth on inner side at midheight; posterior side with 3 bristles in row (1 long with smaller bristle on each side) and 1 long bristle proximal to row. 3rd exopodial joint with 3 bristles on inner lobe and 2 on outer lobe. 4th and 5th exopodial joints fused, with total of 4 bristles.
Sixth Limb: With 1 epipodial bristle. Endite I with 3 bristles; endite II with 2 or 3 bristles; endites III and IV each with 5 bristles. End joint not projecting posteriorly, with 4 anterior spinous bristles followed by short space and 2 plumose bristles. Limb hirsute.
Seventh Limb: 2 bristles in proximal group (1 on each side); 5 bristles on terminal segment (2 on comb side, 3 on peg side), each bristle with 1 to 4 bells and distal marginal spines; terminal comb with 5-7 recurved teeth; 2 or 3 spinous pegs opposite comb.
Furca: Each lamella with 6 claws; claws 1,2, and 4 stout; claws 3,5, and 6 short, slender, medial row of teeth on claw 1 with large teeth distally; 1 or 2 small rounded teeth on lamella following claws. Right lamella with few spines along anterior edge and long hairs forming rows on medial side near anterior margin. Hairs present laterally on lamellae following claws. Right lamella anterior to left by width of base of claw 1.
Bellonci Organ: Elongate, with 5 weak proximal sutures and small spine at tip.
Eyes: Lateral eye small, unpigmented, with 4 or 5 minute amber-colored divided ommatidia and many smaller cells. Medial eye partly fragmented.
Upper Lip: With 2 fairly large glandular tubes at tip.
Genitalia: USNM 193923 with oval ring with attached spermatophore on each side of body anterior to furca.
Y-Sclerite: With well-developed ventral branch.
Eggs: USNM 193923 with unextruded eggs in ovaries.
Holotype with 4 eggs in marsupium; length of typical egg 0.33 mm.
DESCRIPTION OF ADULT MALE.— Shape of carapace similar to that of adult female except for dorsal margin having greater slope posteriorly,and for being smaller.
Ornamentation: Similar to that of adult female.
Infold: Rostral and anteroventral infolds similar to those of adult female. Ridge of caudal process with 5 or 6 frond-like bristles.
Carapace Size (length, height in mm): USNM 193924, 1.35,0.69.
First Antenna: 1st joint bare. 2nd joint with 1 dorsal bristle distal to middle. 3rd joint short with 3 bristles (1 ventral, 2 dorsal). 4th joint long with 1 dorsal bristle. 5th joint wedged ventrally between 4th and 6th joints; stem with bulbous proximal part with abundant filaments, 2-4 short filaments near midlength, and 2 spines or papillae at tip. Long 6th joint with short medial bristle. 7th joint: a-bristle twice length of bristle of 6th joint; b-bristle about twice length of a-bristle, with 2 filaments near midlength and 2 papillae at tip; c-bristle long with 6 filaments and bifurcate tip, each with papilla. 8th joint: d- and e-bristles as long as c-bristle, bare with blunt tips; f-bristle almost as long as c-bristle with 7 filaments and bifurcate tip, each with terminal papilla; g-bristle similar to c-bristle.
Second Antenna: Protopodite bare. Endopodite 3-jointed: 1st joint short with 3 or 4 small ringed bristles; 2nd joint elongate with 2 long spinous proximal bristles; 3rd joint reflexed, with 0 or 1 small proximal bristle and 2 slender subterminal bristles; tip of joint with few minute ridges (right limb of USNM 193925 aberrant in having distal 3rd bent appearing to form 4th joint). Exopodite: 1st joint with minute medial bristle on terminal margin; bristles of joints 2-8 differ from those of adult female in having spines restricted to proximal 1/3 to l/2, and longer natatory hairs on distal 1/2 to 2/3; bristles also with long hairs on long segment proximal to 1st spine; 9th joint with 2 bristles (longer similar to others, shorter with many slender spines); basal spines on joints similar to those of adult female; joints 2-8 with row of minute spines along distal edges.
Mandible: Coxale endite represented by minute indistinct spine. Basale with same number of bristles as on adult female, but 4 medial bristles weaker, and the single ventral and 2 lateral bristles much longer, dorsal bristles similar those of adult female. Exopodite and 1st endopodial joint similar to those of adult female. 2nd endopodial joint: with 3 dorsal bristles, and 4 ventral bristles in 2 groups, each with 2 bristles (medial bristle of proximal ventral group much longer than that of adult female). 3rd endopodial joint with 2 long claws, 1 minute dorsal claw, and 3 ringed bristles (the 2 long claws much longer than those of adult female).
Maxilla: Limb reduced. Dorsal margins of precoxale, coxale, and basale with fringe of long hairs; coxale with dorsal bristle; endite I with 5 or 6 unringed weak bristles; endite II with 5 unringed weak bristles; endite III with 7 unringed bristles (1 proximal, 2 distal, 4 terminal, all except one terminal bristle weak). Basale with long, ringed, strong, dorsal bristle and 2 long, unringed, weak, ventral bristles. Exopodite with 3 ringed strong bristles (middle bristle with long hairs). 1st endopodial joint with long hairs and 2 unringed weak beta-bristles (alpha-bristle not observed, possibly broken off). 2nd endopodial joint with 6 unringed weak bristles, some with a minute tubular process at tip.
Fifth Limb: Limb reduced. Epipodite with 41 bristles. Endites I—III and 1st and 2nd exopodial joints with mostly unringed weak bristles. 3rd exopodial joint with 3 weak bristles on inner lobe and 2 stronger ringed bristles on outer lobe. 4th and 5th joints fused, with 4 ringed strong bristles.
Sixth Limb: With 1 epipodial bristle. Endite I with 3 small bristles; endite II with 3 bristles; endites III and IV each with 5 bristles. End joint with 3 anterior bristles with long and short spines and 2 plumose posterior bristles. All bristles strong and ringed. (Limb similar in size to that of adult female but some bristles of endites III and IV much longer.)
Seventh Limb: Without proximal bristles; terminal segment with 4 equilength bristles, 2 on each side, each with 4 bells and few distal marginal spines. Terminus with comb of 4 or 5 alate teeth and small triangular spine between teeth; side opposite comb bare.
Furca: Same number and distribution of claws as on adult female, but claws 1 and 2 longer, and claw 1 without distal larger teeth in medial row. USNM 193924 with 2 or 3 low rounded teeth on lamella following claws.
Bellonci Organ: Similar to that of adult female.
Eyes: Medial eye small, unpigmented. Lateral eye about same size as medial eye, with 5 well-developed, light amber-colored ommatidia (eye similar in size to that of adult female, but more distinct and with larger ommatidia).
Upper Up: Similar to that of adult female.
Genitalia: With lobate copulatory organ with bristles and terminal hook with 5 or 6 distinct teeth.
Anterior of Body: Without anterior process.
Posterior of Body: Evenly rounded, bare.
Y-Sclerite: Similar to that of adult female.
DESCRIPTION OF INSTAR III MALE.— Carapace similar in shape to that of adult female.
Carapace Size (length, height in mm): 1.02, 0.50.
First Antenna: 1st joint bare. 2nd joint with 1 dorsal bristle. 3rd joint with 3 bristles (1 ventral, 2 dorsal). 4th joint with 2 bristles (2 ventral, 1 dorsal). Joints 5-8 with same number of bristles as on adult female; filaments not counted on bristles having them.
Second Antenna: Protopodite bare. Endopodite 3-jointed: 1st joint with 2 small proximal bristles; 2nd joint elongate with 2 long ventral bristles; 3rd joint elongate with small terminal process (process present on both limbs). Exopodite: similar to that of adult female except terminal closely ringed section of bristles bare and only about 1/5 length of bristle; 9th joint with 2 bristles.
Mandible, Maxilla, and Fifth Limb: Well developed but not examined in detail.
Sixth Limb: With many bristles.
Seventh Limb: Elongate, bare.
Furca: Similar number and distribution of claws as on adult female.
Bellonci Organ: Not observed.
Eyes: Lateral eye small with 5 minute ommatidia. Medial eye not observed.
Genitalia: Absent.
Anterior of Body: With low rounded anterior process.
Posterior of Body: Evenly rounded, bare.
COMPARISONS.—The triangular shape of H. vatrax when viewed anteriorly or posteriorly separates it from other species referred to the genus.
REMARKS.—The juvenile (instar III male) examined is without natatory hairs on exopodial bristles of the 2nd antenna indicating that the juvenile is either not an efficient swimmer or incapable of swimming. The distal 1/4 to 1/3 of some exopodial bristles of the adult female bear natatory hairs indicating that adult females are capable of swimming. The hairs are thinner and much shorter than those of the adult male. The exopodial bristles of the adult male bear long natatory hairs on the distal 1/2 to 2/3 and males are probably more powerful swimmers than adult females. The sample from Slope 1 contains 31 specimens of the species; most are adult females, and only 1 is an adult male, suggesting that adult males are relatively sparse in the benthos. Only 1 adult female has eggs in the marsupium but many have unextruded eggs.”
(Kornicker, 1995, pp. 21-27)
