Junctichela margalefi Kornicker & Caraion 1978

Junctichela margalefi

HOLOTYPE.—“Grigore Antipa” 296, A–1 female, length 1.29 mm, height 0.97 mm, in alcohol and on slides.

TYPE-LOCALITY.—Station X074.

ETYMOLOGY.—The species is named for Dr. Ramon Margalef, Instituto de Investigaciones Pesqueras, Barcelona, Spain.

ALLOTYPE.—USNM 153925, adult male from same sample as holotype.

PARATYPES.—From station X075: USNM 141268, 1 ovigerous female; USNM 156616, 1 instar II; USNM 156617, 1 A–2 female; “Grigore Antipa” 298, 2 juveniles. Thalassa sample (no station number in vial) probably from off Mauritania: USNM 156618, 2 juveniles. From station X066: USNM 156630, 3 adult males; USNM 156631, 1 adult female plus 9 specimens.

DESCRIPTION OF ADULT FEMALE (Figures 42, 43; Plate 27).—Carapace oval in lateral view with minute incisur and small caudal process; carapace widest in posterodorsal part (Figures 42, 43a).

Ornamentation: Surface with ovoid shallow fossae (Figure 42; Plate 27a); area between fossae with abundant bristles with rounded tips (Plate 27b,c,e,f); organic matrix present between bristles; on dried specimen organic matrix tends to form film over bristles and across tops of some fossae (Plate 27d,f).

Infold: Anterior infold with minute bristle below incisur (Figure 43b); infold of caudal process with 8 bristles forming row in addition to several bristles along inner margin; posterior infold above caudal process with 2 setose bristles (Figure 43c,d).

Central Adductor Muscle Attachments: Consisting of about 13 individual ovoid attachments.

Selvage: Wide lamellar prolongation present along anterior, ventral, and posterior margins.

Size: USNM 141268, length 1.56 mm, height 1.31 mm; USNM 156631a, length 1.54 mm, height 1.15 mm.

First Antenna (Figure 43e): 1st joint: lateral surface with short spines near dorsal margin. 2nd joint: 1 dorsal bristle. 3rd joint: short, fused to 4th, with 2 spinous bristles (1 ventral, 1 dorsal). 4th joint: elongate, with 3 spinous bristles (2 ventral, 1 dorsal). 5th joint: long, sensory bristle bare, terminating in minute spine. 6th joint: fused to 5th, with short spinous medial bristle. 7th joint: a-bristle spinous, almost twice length of bristle of 6th joint; b-bristle bare, longer than a-bristle; c-bristle similar to sensory bristle of 5th joint but slightly longer. 8th joint: d- and e-bristles bare, about three-fourths length of c-bristle; f- and g-bristles similar to c-bristle but slightly shorter.

Second Antenna: Protopodite bare. Endopodite 1-joined with 2 minute anterior bristles and 1 spinous terminal bristle on small mound (mound could be interpreted as 2nd joint) (Figure 43f). Exopodite: 1st joint with recurved medial spine on distal margin; bristle of 2nd joint with 9 stout, widely separated, ventral spines proximally, and natatory hairs distally along both margins; bristles of joints 3–8 with ventral spines proximally and natatory hairs distally. 9th joint with 2 bristles (ventral bristle long with spines ventrally and natatory hairs distally, dorsal bristle short with short marginal spines). Joints 3–7 with minute lateral spines forming row along distal margin near base of bristle, no basal spines present.

Mandible (Figure 43g): Coxale consisting of stout spine; ventral margin of coxale hirsute. Basale: ventral margin with 4 bristles, some with bases on medial side; lateral side near ventral margin with 2 short bristles; dorsal margin with 1 short bristle distal to middle and 1 subterminal. Exopodite absent. Endopodite: 1st joint with distal medial spines, spines along terminal dorsal corner, and main ventral claw; 2nd joint with subterminal bristle on dorsal margin and main ventral claw; end joint with minute ventral and dorsal bristle at base of main claw; tips of claws on specimen examined appearing worn.

Maxilla (Figure 43h): Precoxale and coxale with fringe of long hairs; coxale with short dorsal bristle. Endite I with about 5 bristles; endite II with about 4 bristles; endite III with 5 bristles. Basale with slender bristle near base of exopodite. Exopodite with 1 short bare bristle and 1 long spinous bristle. Endopodite: 1st joint with stout pectinate α- and β-bristles; 2nd joint with 2 a-bristles, 1 c-bristle, and 5 pectinate end bristles.

Fifth Limb (Figure 43i): Epipodial appendage with 33–35 bristles. Single endite with 1 short bristle. Exopodite: 1st joint with 2 bristles; joints 2–5 hirsute, fused; 2nd joint with 3 bristles; fused joints 3–5 with total of 5 bristles.

Sixth Limb (Figure 43j,l): Single endite with 3 bristles; end joint with 13–14 spinous ventral bristles in addition to 2 stout, hirsute, posterior bristles; lateral and medial surfaces with short spines forming rows; medial surface near posterior margin with abundant long hairs.

Seventh Limb (Figure 43k): Each limb with 8 bristles (2 in proximal group, 1 on each side, and 6 in terminal group, 3 on each side), each bristle with 2–5 bells and without marginal spines; terminus with opposing combs, each with 5 or 6 teeth.

Furca (Figure 43l): Each lamella with 5 claws; claws 1–3 fused to lamella, claws 4 and 5 separated from lamella by suture; teeth present along posterior margins of claws 1–3; finer spines present along anterior margins of same claws; USNM 141268 with tips of claws broken.

Rod-shaped Organ (Figure 43n): Crinkled proximally, broadening distally, with rounded tip.

Eyes: Lateral eye small with 4 ommatidia (Figure 43m); medial eye pigmented, bare, about twice diameter of lateral eye (Figure 43n).

Upper Lip (Figure 43n,o): With 2 rounded processes projecting anteriorly.

Genitalia (Figure 43l): Visible as oval sclerotized ring.

Brushlike Organ (Figure 43p): Consisting of about 5 minute bristles.

Y-Sclerite (Figure 43p): Typical for family.

Eggs: USNM 141268 with 5 eggs in marsupium in addition to unextruded eggs. (See Figure 43a for position of eggs in marsupium.)

DESCRIPTION OF ADULT MALE (Figure 44, 45).—Carapace more elongate than that of female, with more prominent rostrum and truncate posterior (Figure 44).

Ornamentation (Figure 44): Similar to that of female.

Infold: Not examined.

Central Adductor Muscle Attachments: Similar to those of female.

Size: USNM 153925, length 1.40 mm, height 0.89 mm. USNM 156630, 3 specimens: length 1.31 mm, height 0.89 mm; length 1.33 mm, height 0.89 mm; length 1.34 mm, height 0.86 mm.

First Antenna (Figure 45a): 1st joint: bare. 2nd joint: spinous dorsal bristle. 3rd joint: fused to 4th, with minute ventral bristle and short, slender, dorsal bristle. 4th joint: elongate, with 3 bristles (2 ventral and 1 dorsal). 5th joint: wedged between 4th and 6th joints at ventral margin; sensory bristle of 5th joint with cuplike proximal part with abundant filaments; main stem of sensory bristle with 4 marginal filaments and bifurcate tip. 6th joint; short medial bristle. 7th joint: a-bristle spinous, about three times length of bristle of 6th joint; b-bristle bare, about same length as a-bristle; c-bristle with 3 or 4 marginal filaments and bifurcate tip, about same length as sensory bristle of 5th joint. 8th joint: d- and e-bristles bare, about same length as c-bristle; f-bristle with 3 marginal filaments, slightly shorter than c-bristle; g-bristle with 4 or 5 marginal filaments and bifurcate tip, about same length as c-bristle; minute spine at ends of some filaments, and tips of sensory, c-, f-, and g-bristles.

Second Antenna: Protopodite bare. Endopodite 1-jointed or weakly 2-jointed, with 2 small anterior bristles and 3 spinous terminal bristles on small mound which could be considered a 2nd joint (Figure 45c). Exopodite (Figure 45b): 1st joint wtih recurved medial spine on distal margin; bristle of 2nd joint with 6 stout, widely separated, stout ventral spines proximally and natatory hairs distally; bristles of joints 3–8 with proximal ventral spines, distal natatory hairs, and few hairs proximal to spines; 9th joint: 2 bristles (ventral long bristle with proximal ventral spines and distal natatory hairs; dorsal short bristle with natatory hairs); joints 2–7 with short spines forming lateral row along distal margins; no basal spines present.

Mandible (Figure 45d): Coxale endite represented by slender spine; ventral margin of coxale bare. Basale: medial side near ventral margin with 4 bristles; lateral side near ventral margin with 2 bristles; dorsal margin with 2 fairly long subterminal bristles. Exopodite absent. Endopodite: 1st joint with numerous slender spines on medial surface and along dorsal margin, ventral margin with 1 short bare bristle and 1 longer bristle with short marginal spines; 2nd joint with spines on medial surface, along distal edge near dorsal margin on lateral side, and at terminal end of dorsal margin, dorsal margin with long bare bristle with sharp recurved knifelike tip, ventral margin with 2 short bristles; end joint with minute dorsal and ventral bristle at base of stout, short, bare claw.

Maxilla (Figure 45e): Limb reduced. Endites I–III with weakly developed bristles, some with long marginal hairs. Coxale with short dorsal bristle and dorsal fringe of hairs; bristles and claws of end joint weakly developed. Exopodite represented by a long and short bristle with base on 1st endopodite joint near distal margin of basale, no lobe observed.

Fifth Limb (Figure 45f): Epipodial appendage with 34 bristles. Single endite with 1 short bristle. Exopodite: 1st joint with 2 hirsute bristles; joints 2–5 hirsute, fused; 2nd joint with 3 hirsute bristles; fused joints 3–5 with total of 5 hirsute bristles.

Sixth Limb (Figure 45g): Single endite with 3 short bristles; end joint with 13 bristles with long marginal hairs in addition to 2 hirsute posterior bristles; medial surface of limb hirsute; lateral surface with short spines forming rows except for long hairs near posterior margin.

Seventh Limb (Figure 45h): Represented by bare crinkled stump.

Furca (Figure 45i): Each lamella with 5 claws as on adult female; lamella differs from that of female in having a small spine between 4th and 5th claws, and 5 or 6 spines following the 5th claw.

Rod-shaped Organ (Figure 45k): Segmented proximal part (distal end broken off specimen examined).

Eyes (Figure 45j,k): Lateral and medial eyes similar to those of female.

Copulatory Organ (Figure 45i): Consisting of 2 or 3 lobes, one of these with long sclerotized terminal hook and several bristles.

Y-Sclerite (Figure 45i): Similar to that of female.

DESCRIPTION OF INSTAR II (sex uncertain; Figure 46a–f): Carapace similar to that of adult female except for posterior dorsal to caudal process being truncate (Figure 47a).

Size: USNM 156616, length 0.82 mm, height 0.58 mm.

First Antenna: Similar to that of adult female except 4th joint without ventral bristles.

Second Antenna: Similar to that of adult female except endopodite with only 1 short anterior bristle.

Mandible, Maxilla: Similar to that of adult female.

Fifth Limb: Epipodial appendage with 30 bristles. Exopodite similar to that of adult female.

Sixth Limb (Figure 46b): Hirsute with 1 spinous bristle.

Seventh Limb (Figure 46c): Very small (observed only under oil immersion, but could not be certain that structure observed is 7th limb).

Furca (Figure 46d): Similar to that of adult female.

Rod-shaped Organ (Figure 46e), Eyes, and Y-Sclerite: Similar to those of adult female.

Brushlike Organ: Not present.

DESCRIPTION OF A–2 FEMALE (instar III; Figure 46g–l).—Carapace similar to that of adult female except for posterior dorsal to caudal process being truncate (Figure 46g).

Size: USNM 156617, length 1.08 mm, height 0.84 mm.

First Antenna: Similar to that of adult female except only 1 ventral bristle on 4th joint.

Second Antenna (Figure 46h), Mandible, Maxilla, 5th and 6th Limbs: Not examined in detail but similar to those of adult female.

Seventh Limb (Figure 46i): Long but without bristles or terminal comb teeth.

Furca, Rod-shaped Organ, and Eyes: Similar to those of adult female.

DESCRIPTION OF A–1 FEMALE (instar IV; Figures 46j–l, 47).—Carapace similar to that of adult female except for having truncate posterior (Figure 46j, 47).

Size: “Grigore Antipa” 296, length 1.29 mm, height 0.97 mm.

First Antenna: Similar to that of adult female.

Second Antenna: Similar to that of adult female except exopodial bristles with more ventral spines.

Mandible, Maxilla, 5th and 6th Limbs: Similar to those of adult female.

Seventh Limb: Bristles strongly tapered (juvenile character); 2 bristles in proximal group (1 on each side), 4 bristles in terminal group (2 on each side), each bristle with 2–4 bells; terminus with opposing combs.

Furca (Figure 46k): Similar to that of adult female except for having 2 spines following claw 5; long medial hairs forming row at base of claw 1 on each lamella.

Rod-shaped Organ and Eyes (Figure 46l): Similar to those of adult female.

SUMMARY OF DEVELOPMENT OF FEMALE.—Using the key to early myodocopid instars of Kornicker (1969a:3) it was determined that the collection contained instars II (A–3) to IV (A–1) in addition to the adult. Observed changes in carapace size and in the number of bristles on limbs are summarized in Table 2. The development of Junctichela differs from that of Spinacopia (see Kornicker, 1969a:34) mainly in that the number of furcal claws remained the same during development from instar II to the adult of Junctichela but increased from 4 claws on instar II to 7–8 claws on the adult of Spinacopia. The number of furcal claws during the development from instar II to the adult of Sarsiella zostericola Cushman, 1906, also remains the same (Kornicker, 1967:4).

RUTIDERMATIDAE Brady and Norman, 1896

This family contains three genera: Rutiderma Brady and Norman, 1896, Alternochelata Kornicker, 1958, and Scleraner Kornicker, 1975a. Only the first two are represented in the collections.