Nealella lux Kornicker 1994

“Nealella lux, new species

Figures 98-100

ETYMOLOGY.—From the Latin lux (light).

HOLOTYPE.—Adult female on slide and in alcohol in 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 193941, adult female on slide and in alcohol; USNM 193942, undissected A-l male.

DISTRIBUTION.—Slope 1, 204 m.

DESCRIPTION OF ADULT FEMALE.— Carapace elongate with overhanging rostrum, small incisur, and projecting caudal process; dorsal margin straight in vicinity of hinge line; posterodorsal corner of valve prominent.

Ornamentation: Surface with numerous irregular large fossae; raised flat borders between fossae appearing smooth but with abundant minute papillae visible best along valve margins at high magnification (x40 objective, xl5 ocular) and with row of widely spaced larger papillae. Bristles (some divided) very sparse on lateral surface but more numerous on inner surface along anterior, anteroventral and ventral margins.

Infold: Rostral infold with row of 3 bristles; a longer bristle (with broad basal part) anterior to row is interpreted to be on exterior surface of shell rather than on infold; single bristle present at inner end of incisur; anteroventral infold with short bristle near incisur separated by space from row of 7-9 longer setose bristles with bases just distal to narrow list. Infold of caudal process with row of 8 broad setose bristles along ridge anterior to pocket, 1 small bare bristle anterior to row of setose bristles, and 2 pairs of bare bristles along inner edge of infold near ventral margin of valve; 2 small pores with minute spines present along posterior edge of caudal process.

Selvage: Anterodorsal margin of valve with lamellar prolongation (wider and striate on right valve only) reaching anteriorly just past insertions of row of 3 bristles on rostral infold; lamellar prolongation absent in vicinity of rostrum and anterior 1/3 of ventral margin; broad lamellar prolongation along posterior 2/3 of ventral margin (with anterior end at posterior bristle of row of bristles along anteroventral infold; anterior end of prolongation with marginal fringe of long hairs); ventral prolongation narrow along ventral edge of caudal process; prolongation absent along posterior edge of caudal process, and narrow along dorsal edge of caudal process and posterior edge of valve dorsal to caudal process.

Central Adductor Muscle Attachments: Comprising about 19 individual attachments.

Carapace Size (length, height in mm): USNM 193941, 1.21, 0.68; holotype, 1.14, 0.66.

First Antenna: 1st joint bare. 2nd joint with spinous dorsal bristle, rows of medial and ventral spines, and row of lateral spines along distal margin. 3rd joint fused to 4th, with 1 spinous dorsal bristle; 4th joint with 3 spinous terminal bristles (1 dorsal, 2 ventral). Long ventral bristle of 5th joint with several small filaments, distal ventral spines, and spine at tip. 6th joint fused to 5th, with short spinous medial bristle. 7th joint: a-bristle spinous, about twice length of bristle of 6th joint; b-bristle about 1 xli times length of a-bristle, with spine at tip; c-bristle same length as bristle of 5th joint, almost twice length of b-bristle, with several small filaments, distal ventral spines, and spine at tip. 8th joint: d- and e-bristles slightly shorter than c-bristle, bare with blunt tips; f- bristle shorter than c-bristle, with several filaments and distal ventral spines; g-bristle same size as c-bristle with several short filaments and distal ventral spines. (Note: marginal spines on bristle of 5th joint, c-bristle of 7th joint, and f- and g-bristles of 8th joint unusual.).

Second Antenna: Protopodite bare. Endopodite 2-jointed: 1st joint with 1 proximal bristle; 2nd joint comprising small bare node. Exopodite: 1st joint with minute medial terminal bristle; bristle of 2nd joint with proximal ventral spines and distal natatory hairs; bristles of joints 3-8 with a few proximal dorsal hairs, then proximal ventral spines and distal natatory hairs; 9th joint with 2 bristles (ventral medium length with proximal ventral spines and distal natatory hairs, dorsal short with small hairs); joints 2-8 with minute spines forming row along distal margins.

Mandible: Coxale endite a stout tooth with 1 stout and several slender spines near base and small distal spines. Coxale with slender ventral spines. Basale: lateral side near ventral margin with row of 3 spinous ringed bristles; medial side near ventral margin with 5 bristles (distal longest); dorsal margin with 1 small ringed bristle at distal 2/3 and 2 ringed subterminal bristles (lateral short, medial long). Exopodite minute (broader on USNM 193941 than on illustrated holotype) with short bare ringed bristle. 1st endopodial joint short: lateral side with row of spines along distal edge near dorsal margin; medial side with 2 rows of short spines near midwidth; ventral margin with 3 short ringed bristles. 2nd endopodial joint: dorsal margin with 3 short ringed distal bristles; ventral margin with 1 small unringed spinous subterminal bristle (USNM 193941 with few ventral spines proximal to bristle); lateral surface with small spines near subterminal ventral bristle, a row of spines in distal ventral corner near base of long terminal claw, and a short broad spine just dorsal to base of terminal claw; terminal claw with proximal ventral and dorsal spines and with prolonged narrow tip; medial side with 3 rows of short spines and broad terminal translucent shield medial to base of terminal bristle. 3rd endopodial joint with 2 long terminal claws with prolonged narrow tips (lateral claw with ventral spines at base; medial claw with small hemispherical basal socket, and 4 bristles (1 long ringed spinous ventral, 3 dorsal indistinct (1 long, 2 short proximal (1 short bristle could be a claw))). (Note: translucent shield on 2nd endopodial joint unusual.)

Maxilla: Coxale with plumose dorsal bristle and fringe of dorsal hairs. Endite I fragmented but with 4 bristles on remaining part; endites II and III each with 6 bristles. Basale with dorsal hairs and plumose bristle near exopodite. Exopodite well developed, with 3 equilength plumose terminal bristles. 1st endopodial joint with rows of spines on both anterior margin and medial surface near anterior margin, 1 slender spinous alpha-bristle, and 1 stouter spinous beta-bristle (tip broken off on illustrated limb). 2nd endopodial joint with 2 closely spaced lateral spinous a-bristles, 1 slender medial spinous c -bristle, and 5 end bristles: anterior bristle ringed in distal half, with stout spines on unringed part, slender spines on ringed part, and with terminal hook-like spine; posterior bristle unringed, with indistinct marginal teeth and distal flange; remaining 3 bristles unringed, with stout proximal teeth and distal flanges.

Fifth Limb: Epipodite with 37 bristles. Single endite with 1 bristle. 1st exopodial joint with 2 bristles (2nd bristle broken off on illustrated limb). 2nd exopodial joint, inner lobe of 3rd joint and 4th joint not well defined, and interpretation uncertain, with total of 9 bristles; outer lobe of 3rd joint with 2 bristles; 5th joint forming separate lobe with 3 bristles (lobe could be interpreted as fused 4th and 5th joints). Exopodial joints 2-4 hirsute.

Sixth Limb: Endite I with 3 spinous bristles (2 short, long 1 long); endite II with 2 spinous bristles; endite III with 4 or 5 spinous bristles; endite IV with 4 spinous bristles (this endite could be interpreted to be part of end joint; endite more clearly separated from end joint in USNM 193942 than in USNM 193941). End joint with 2 bristles with long marginal hairs. 1 bristle proximal to end joint interpreted to be epipodial bristle. Lateral surface with rows of spines on endites II-IV; medial surface of limb with abundant long hairs. All bristles ringed.

Seventh Limb: Four bristles in proximal group, 2 on each side, each with 3 or 4 bells; 4 bristles in terminal group, 2 on each side, each with 5 or 6 bells. Terminus with comb of 7 alate teeth opposite 2 inward pointing pegs with indistinct marginal spines.

Furca: Each lamella with 6 claws; claw 1 nonarticulated; claw 3 slenderer than claw 4; claws 1, 2, and 4 with teeth along posterior edge; claws 1 and 2 also with row of medial teeth; claws 3, 5, and 6 with slender teeth along both anterior and posterior edges; row of long medial hairs present at base of claw 1; right lamella anterior to left by width of base of claw 1 and with spines along anterior margin. Teeth of claws not shown.

Bellonci Organ: Elongate, with about 5 sutures at midlength and rounded tip.

Eyes: Lateral eye small, unpigmented, with 5 divided ommatidia. Medial eye slightly larger than lateral eye, bare, with brown pigment.

Upper Lip: Simple lobe, hirsute.

Genitalia: Concave disc on each side of body anterior to furca (spermatophore absent).

Posterior of Body: Evenly rounded, bare.

Y-Sclerite: With ventral branch.

Eggs: USNM 193941 and holotype with few large unextruded eggs.

DESCRIPTION OF A-l MALE.—Carapace similar in shape and ornamentation to that of adult female.

Carapace Size (length, height in mm): USNM 193942, 1.01, 0.62.

Second Antenna: Endopodite very long and with 1 or 2 small terminal bristles (not examined in detail).

Seventh Limb: Well developed and bearing bristles (not examined in detail).

COMPARISONS.—Nealella lux is the only known species in the subfamily without a bristle on the 2nd endopodial joint of the 2nd antenna of the female. The short 1st endopodial joint of the mandible with only 3 short ventral bristles and no stout claws differs from other known species of Nealella. N. lux unlike N. queenslandensis, N. muelleri Kornicker and Caraion, 1980, and N. monothrix Kornicker and Caraion, 1980, does not have an extremely long terminal bristle on the 7th limb. Whether N. ornithoides or Nealella species A has a long bristle is not known.”

(Kornicker, 1994, p.173-177)

Nealella lux

ETYMOLOGY.—From the Latin lux (light).

HOLOTYPE.—Adult female on slide and in alcohol in 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 193941, adult female on slide and in alcohol; USNM 193942, undissected A-l male.

DISTRIBUTION.—Slope 1, 204 m.

DESCRIPTION OF ADULT FEMALE (Figures 98–100a–g).—Carapace elongate with overhanging rostrum, small incisur, and projecting caudal process (Figure 98a–d); dorsal margin straight in vicinity of hinge line; posterodorsal corner of valve prominent.

Ornamentation: Surface with numerous irregular large fossae (Figure 98e) (fossae stippled but not all shown in Figure 98a,c); raised flat borders between fossae appearing smooth but with abundant minute papillae visible best along valve margins at high magnification (×40 objective, ×l5 ocular) and with row of widely spaced larger papillae (small circles in Figure 98e). Bristles (some divided) very sparse on lateral surface but more numerous on inner surface along anterior, anteroventral and ventral margins (Figure 98f,g).

Infold: Rostral infold with row of 3 bristles; a longer bristle (with broad basal part) anterior to row is interpreted to be on exterior surface of shell rather than on infold (Figure 98f,h); single bristle present at inner end of incisur; anteroventral infold with short bristle near incisur separated by space from row of 7–9 longer setose bristles with bases just distal to narrow list. Infold of caudal process with row of 8 broad setose bristles along ridge anterior to pocket, 1 small bare bristle anterior to row of setose bristles, and 2 pairs of bare bristles along inner edge of infold near ventral margin of valve (Figure 98g); 2 small pores with minute spines present along posterior edge of caudal process.

Selvage: Anterodorsal margin of valve with lamellar prolongation (wider and striate on right valve only) reaching anteriorly just past insertions of row of 3 bristles on rostral infold (Figure 98h); lamellar prolongation absent in vicinity of rostrum and anterior of ventral margin; broad lamellar prolongation along posterior of ventral margin (with anterior end at posterior bristle of row of bristles along anteroventral infold; anterior end of prolongation with marginal fringe of long hairs) (Figure 98d); ventral prolongation narrow along ventral edge of caudal process; prolongation absent along posterior edge of caudal process, and narrow along dorsal edge of caudal process and posterior edge of valve dorsal to caudal process.

Central Adductor Muscle Attachments (Figure 98a): Comprising about 19 individual attachments.

Carapace Size (length, height in mm): USNM 193941, 1.21, 0.68; holotype, 1.14, 0.66.

First Antenna (Figure 99a,h,i): 1st joint bare. 2nd joint with spinous dorsal bristle, rows of medial and ventral spines, and row of lateral spines along distal margin. 3rd joint fused to 4th, with 1 spinous dorsal brisde; 4th joint with 3 spinous terminal bristles (1 dorsal, 2 ventral). Long ventral brisde of 5th joint with several small filaments, distal ventral spines, and spine at tip. 6th joint fused to 5th, with short spinous medial bristle. 7th joint: a-bristle spinous, about twice length of brisde of 6th joint; b-bristle about 1 times length of a-bristle, with spine at tip; c-bristle same length as brisde of 5th joint, almost twice length of b-bristle, with several small filaments, distal ventral spines, and spine at tip. 8th joint: d- and e-bristles slightly shorter than c-bristle, bare with blunt tips; f- bristle shorter than c-bristle, with several filaments and distal ventral spines; g-bristle same size as c-bristle with several short filaments and distal ventral spines. (Note: marginal spines on bristle of 5th joint, c-bristle of 7th joint, and f- and g-bristles of 8th joint unusual.) (Figure 99i).

Second Antenna: Protopodite bare (Figure 99f). Endopodite 2-jointed (Figure 99j): 1st joint with 1 proximal bristle; 2nd joint comprising small bare node. Exopodite: 1st joint with minute medial terminal brisde; bristle of 2nd joint with proximal ventral spines and distal natatory hairs; bristles of joints 3–8 with a few proximal dorsal hairs, then proximal ventral spines and distal natatory hairs; 9th joint with 2 bristles (ventral medium length with proximal ventral spines and distal natatory hairs, dorsal short with small hairs); joints 2–8 with minute spines forming row along distal margins.

Mandible (Figures 99b, 100a–c): Coxale endite a stout tooth with 1 stout and several slender spines near base and small distal spines (detail in Figure 100a). Coxale with slender ventral spines. Basale (Figure 100a): lateral side near ventral margin with row of 3 spinous ringed bristles; medial side near ventral margin with 5 bristles (distal longest); dorsal margin with 1 small ringed bristle at distal and 2 ringed subterminal bristles (lateral short, medial long). Exopodite minute (broader on USNM 193941 than on illustrated holotype) with short bare ringed bristle. 1st endopodial joint short (Figure 100a): lateral side with row of spines along distal edge near dorsal margin; medial side with 2 rows of short spines near midwidth; ventral margin with 3 short ringed brisdes. 2nd endopodial joint (Figures 99b, 100a–c):dorsal margin with 3 short ringed distal bristles; ventral margin with 1 small unringed spinous subterminal bristle (USNM 193941 with few ventral spines proximal to bristle (Figure 99b)); lateral surface with small spines near subterminal ventral bristle, a row of spines in distal ventral comer near base of long terminal claw, and a short broad spine just dorsal to base of terminal claw (Figure 100c); terminal claw with proximal ventral and dorsal spines and with prolonged narrow tip (Figure 100c); medial side with 3 rows of short spines and broad terminal translucent shield medial to base of terminal bristle (Figures 99b, 100b). 3rd endopodial joint with 2 long terminal claws with prolonged narrow tips (lateral claw with ventral spines at base (Figure 100c, medial claw not shown); medial claw with small hemispherical basal socket (Figures 99b, 100b, lateral claw not shown), and 4 bristles (1 long ringed spinous ventral, 3 dorsal indistinct (1 long, 2 short proximal (1 short bristle could be a claw)) (Figures 99b, 100b)). (Note: translucent shield on 2nd endopodial joint unusual.)

Maxilla (Figure 99c,k): Coxale with plumose dorsal bristle and fringe of dorsal hairs. Endite I fragmented but with 4 bristles on remaining part (Figure 99c); endites II and III each with 6 bristles (Figure 99c). Basale with dorsal hairs and plumose bristle near exopodite (Figure 99k). Exopodite well developed, with 3 equilength plumose terminal bristles. 1st endopodial joint with rows of spines on both anterior margin and medial surface near anterior margin, 1 slender spinous alpha-bristle, and 1 stouter spinous beta-bristle (tip broken off on illustrated limb). 2nd endopodial joint with 2 closely spaced lateral spinous a-bristles, 1 slender medial spinous c-bristle, and 5 end bristles: anterior bristle ringed in distal half, with stout spines on unringed part, slender spines on ringed part, and with terminal hook-like spine; posterior bristle unringed, with indistinct marginal teeth and distal flange; remaining 3 bristles unringed, with stout proximal teeth and distal flanges.

Fifth Limb (Figure 100d): Epipodite with 37 bristles. Single endite with 1 bristle. 1st exopodial joint with 2 bristles (2nd bristle broken off on illustrated limb). 2nd exopodial joint, inner lobe of 3rd joint and 4th joint not well defined, and interpretation uncertain, with total of 9 bristles; outer lobe of 3rd joint with 2 bristles; 5th joint forming separate lobe with 3 bristles (lobe could be interpreted as fused 4th and 5th joints). Exopodial joints 2–4 hirsute.

Sixth Limb (Figure 100e): Endite I with 3 spinous bristles (2 short, long 1 long); endite II with 2 spinous bristles; endite III with 4 or 5 spinous bristles; endite IV with 4 spinous bristles (this endite could be interpreted to be part of end joint; endite more clearly separated from end joint in USNM 193942 than in USNM 193941). End joint with 2 bristles with long marginal hairs. 1 bristle proximal to end joint interpreted to be epipodial bristle. Lateral surface with rows of spines on endites II–IV; medial surface of limb with abundant long hairs. All bristles ringed (rings not shown).

Seventh Limb (Figures 99d, 100f): Four bristles in proximal group, 2 on each side, each with 3 or 4 bells; 4 bristles in terminal group, 2 on each side, each with 5 or 6 bells. Terminus with comb of 7 alate teeth opposite 2 inward pointing pegs with indistinct marginal spines.

Furca (Figure 99e,l): Each lamella with 6 claws; claw 1 nonarticulated; claw 3 slenderer than claw 4; claws 1, 2, and 4 with teeth along posterior edge; claws 1 and 2 also with row of medial teeth; claws 3, 5, and 6 with slender teeth along both anterior and posterior edges; row of long medial hairs present at base of claw 1; right lamella anterior to left by width of base of claw 1 and with spines along anterior margin. Teeth of claws not shown.

Bellonci Organ (Figure 99f,g,m): Elongate, with about 5 sutures at midlength and rounded tip.

Eyes: Lateral eye small, unpigmented, with 5 divided ommatidia (Figure 99f,g,h). Medial eye slightly larger than lateral eye, bare, with brown pigment (Figure 99f,g,m).

Upper Lip (Figure 100g): Simple lobe, hirsute.

Genitalia (Figure 99e): Concave disc on each side of body anterior to furca (spermatophore absent).

Posterior of Body (Figure 99e): Evenly rounded, bare.

Y-Sclerite (Figure 99e): With ventral branch.

Eggs: USNM 193941 and holotype with few large unextruded eggs. Location of 2 different eggs in USNM 193941 shown in Figures 98a, 99e.

DESCRIPTION OF A-1 MALE (Figure 100h).—Carapace similar in shape and ornamentation to that of adult female (Figure 100h).

Carapace Size (length, height in mm): USNM 193942, 1.01, 0.62.

Second Antenna: Endopodite very long and with 1 or 2 small terminal bristles (not examined in detail).

Seventh Limb: Well developed and bearing bristles (not examined in detail).

COMPARISONS.—Nealella lux is the only known species in the subfamily without a bristle on the 2nd endopodial joint of the 2nd antenna of the female. The short 1st endopodial joint of the mandible with only 3 short ventral bristles and no stout claws differs from other known species of Nealella. N. lux unlike N. queenslandensis, N. muelleri Komicker and Caraion, 1980, and N. monothrix Kornicker and Caraion, 1980, does not have an extremely long terminal bristle on the 7th limb. Whether N. ornithoides or Nealella species A has a long bristle is not known.

CYLINDROLEBERIDIDAE Müller, 1906

The Cylindroleberididae include 3 subfamilies: Cylindroleberidinae, Cyclasteropinae, and Asteropteroninae. All have been reported from the vicinity of Australia (Kornicker, 1981c:18), and are represented in the present collection.

CYLINDROLEBERIDINAE Müller, 1906

The Cylindroleberidinae are represented in the collection by 9 genera: Archasterope, Bathyleberis, Domromeus, Homasterope, Parasterope, Skogsbergiella, Synasterope, Xenoleberis, new genus, and an undescribed genus, but only Xenoleberis is described herein.

Xenoleberis, new genus

ETYMOLOGY.—From the Greek Xenos (stranger, guest) plus the Greek leberis (sloughed skin).

TYPE SPECIES.—Xenoleberis bex, new species herein.

COMPOSITION.—The type species plus 2 species previously referred to the genus Bathyleberis: X. californica (Baker, 1979) and X. yamadai (Hiruta, 1979).

DISTRIBUTION.—Xenoleberis bex from south slope of Australia at 600 m. Xenoleberis californica from off Southern California at 9.1–401.4 m (Baker, 1979:288). Xenoleberis yamadai from off the coast of Hokkaido, Japan, at 3–5 m (Hiruta, 1979:99).

DIAGNOSIS.—Female carapace elongate with slightly convex ventral and dorsal margins. Ventral infold with narrow ridge just within valve edge. Carapaces of both male and female X. yamadai with melanophores, but these not reported on other species.

First Antenna: 2nd joint without lateral bristle (always?). Dorsal margin of 3rd joint with 6 spinous bristles. Sensory bristle of female 5th joint relatively short with 1 short slender proximal filament and 6 stouter terminal filaments. d-bristle of 8th joint well developed, bristle-like (tapering to point), without or without marginal spines.

Second Antenna: Endopodite of female with 3 distinct joints and long terminal filament.

Mandible: Basale endite with 3 end bristles (always?). Exopodite less than length of dorsal margin of 1st endopodial joint. Dorsal margin of 2nd endopodial joint without long lateral e-bristle between b- and c-bristles.

Maxilla: Endopodite 2-jointed with short alpha-bristle and long beta-bristle on 1st joint and long terminal bristle on 2nd joint.

The genus is defined mainly on the bristle-like d-bristle of the 8th joint of the 1st antenna, the small exopodite of the mandible, and lack of an e-bristle on the 2nd endopodial joint of the mandible.

COMPARISONS.—Only Bathyleberis Kornicker, 1975:538, and Xenoleberis have well-developed bristle-like (tapering to pointed tip) d-bristles on the 1st antennae. In other genera in the subfamily having well-developed d-bristles, the bristle is filament-like (with parallel sides and blunt tip). The mandible of Xenoleberis differs from that of Bathyleberis in having a much smaller exopodite and in lacking an e-bristle on the 2nd endopodial joint.

REMARKS CONCERNING Bathyleberis californica BAKER, 1979.—I examined a female paratype of B. californica (USNM 151394: appendages on slide; part of body (including lateral eyes) and carapace in alcohol). The lateral eye of the male but not the female was mentioned in the original description of the species. My examination of the female revealed that the lateral eye has 8 distinct ommatidia, the same number as in the male eye. The appendage slide is mostly dried out, but it was observed that the dorsal margin of the 2nd endopodial joint of the mandible has 3 small spines proximal to bristles similar to those of X. bex. I also confirmed that the e-bristle of the 2nd endopodial joint of the mandible is lacking.