Rutiderma darbyi Kornicker 1983

Rutiderma darbyi

Rutiderma dinochelata.—Darby, 1965:28, pl. 13: figs. 1–9, pl. 14: figs. 1–7 [not Rutidermata dinochelata Kornicker, 1958].

Rutiderma darbyi Kornicker.—Bradford, 1980:141, fig. 2 [deliberate nomen nudum].

ETYMOLOGY.—The species is named for Dr. David G. Darby.

HOLOTYPE.—USNM 158003, ovigerous female on slides and in alcohol.

TYPE-LOCALITY.—Georgia continental shelf, 31°05′N, 80°35′W, water depth 26 m (Bureau of Land Management southeast coastal study, sta 0225-3 (5D), 25 Feb 1977).

PARATYPES.—North Carolina continental shelf, Cruise E-8-77: USNM 158566, 1 specimen, sta 005-1; USNM 158567, 1 specimen, sta 006-1. USNM 158185, 1 juvenile, sta 0114-1 (1E). USNM 158186, 2 specimens, sta 0114-3 (1E). USNM 158807, 5 specimens, sta 0118-5. USNM 158831, 1 specimen, sta 0720-5 (1C).

South Carolina continental shelf: USNM 158192, 2 ovigerous females, sta 0131-3 (2B). USNM 158195, 1 ovigerous female, sta 0140-2 (2D). USNM 158182, 1 ovigerous female and 2 juveniles, sta 0146-1 (2E). USNM 158194, 1 ovigerous female; + 1 specimen returned to Linda H. Pequegnat, sta 0170-3 (3C). USNM 158109, 1 specimen with choniostomatid parasite, sta 0177-4 (3E). USNM 158806, 3 specimens, sta 0136-3 (2C). USNM 158805, 2 specimens, sta 0136-5 (2C). USNM 158815, 2 specimens, sta 0136-6 (2C). USNM 158809, 2 specimens, sta 0140-6 (2D). USNM 158799, 1 juvenile, sta 0150-5 (2F). USNM 158796, 2 specimens, sta 0170-4 (3C). USNM 158800, 3 specimens, sta 0170-5 (3C).

Georgia continental shelf: UMMP 48787 (not seen by me but illustrated by Darby, 1965, pl. 13:5; 14:7); UMMP 48788, appendages and valves on 2 slides. USNM 158183, 1 juvenile, sta 0194-3 (4D). USNM 158193, 1 ovigerous female, sta 0194-1 (4D). USNM 158184, 1 juvenile, sta 0215-1 (5B). USNM 158190, 1 juvenile male; USNM 158199, 1 specimen with female choniostomatid parasite; + 2 specimens returned to Linda H. Pequegnat, sta 0215-3 (5B). USNM 158196, 1 ovigerous female + 1 juvenile, sta 0225-2 (5D). USNM 158002, 1 ovigerous female, sta 0225-3 (5D). USNM 158200, 1 ovigerous female, sta 0238-2 (5G). USNM 158830, 1 specimen, sta 0234-5 (5F). USNM 158801, 1 specimen, sta 0220-5 (5C); USNM 158803, 1 specimen, sta 0220-6 (5C). USNM 158816, 1 specimen, sta 0527-1 (5E). USNM 158810, 1 specimen, sta 0531-4 (5F). USNM 158817, 4 specimens, sta 0531-6 (5F). USNM 158813, 1 specimen, sta 0540-5 (5H).

Florida continental shelf (Atlantic): USNM 158188, 1 juvenile; USNM 158191, 1 ovigerous female + 5 juvenile males, sta 0258-1 (6C). USNM 158197, 1 specimen, sta 0258-2 (6C). USNM 158187, 1 specimen, sta 0265-1 (6E). USNM 158198, 1 juvenile male, sta 0265-3 (6E). USNM 158201, 1 specimen, sta 0269-3 (6F). USNM 158797, 4 specimens, sta 0258-4 (6C). USNM 158795, 4 specimens, sta 0258-5 (6C). USNM 158798, 3 specimens, sta 0258-6 (6C). USNM 158814, 3 specimens, sta 0556-6 (7C). USNM 152851, 1 male, Biscayne Key, sta 1. USNM 158189, 1 juvenile male, Biscayne Bay, Rickenbacker Causeway, opposite entrance to Marine Stadium. USNM 156737, 2 juveniles, Virginia Key, northeast shore. USNM 156741, 1 adult male, Biscayne Bay, north end of Virginia Key. USNM 158618, 1 adult female, mouth of Florida Bay.

Florida continental shelf (Gulf of Mexico), transect I: USNM 158678, 158664, 158663, 158707, 158706, 158709, 158785, 158786, 158780, 9 specimens, sta 2101. USNM 158677, 158676, 158705, 158710, 158704, 158770, 158789, 158779, 158777, 14 specimens, sta 2102. USNM 158668, 158673, 158667, 158674, 158670, 158665, 8 specimens, sta 2103. USNM 158782, 158722, 2 specimens, sta 2104. USNM 158679, 9 specimens, sta 2106. Transect II: USNM 158703, 158714, 158773, 158784, 6 specimens, sta 2207. USNM 158712, 158711, 2 specimens, sta 2208. USNM 158716, 1 male, sta 2209. USNM 158718, 158660, 158653, 158658, 5 specimens, sta 2211. Transect III: USNM 158792, 1 juvenile sta 2316. Transect IV: USNM 158758, 158754, 158755, 7 specimens, sta 2419. Transect V: USNM 158759, 158763, 2 specimens, sta 2528. Transect VII: USNM 158787, 1 specimen, sta 2748. Transect IX: USNM 158793, 158776, 158778, 158737, 158739, 7 specimens, sta 2960. Supplemental transect: USNM 158819, 1 adult male, sta 2851. USNM 158828, 158822, 158826, 158820, 158821, 10 specimens, sta 2852.

Florida Continental Shelf (Southwest): USNM 158768, 1 ovigerous female, sta 2853. USNM 158628A,B, 2 specimens, sta 2. Returned to James K. Culter: 1 specimen, sta 14; 6 specimens, sta 16; 87 specimens, sta 20; 5 specimens, sta 22; 1 specimen, sta 28; 15 specimens, vial C; 29 specimens, vial E; 3 specimens, vial L.

Bahama Islands: USNM 158616, 4 juveniles, San Salvador Island. USNM 158617, 1 juvenile, Andros Island, sta 72.

NON-TYPES.—I have examined the appendages of Darby's specimens UMMP 48789 and 48790 and although I refer them here to R. darbyi, I do not consider them paratypes because I have not seen the infold of the caudal process of either specimen; I also refer Darby's UMMP 48786 to R. darbyi but do not consider it to be a paratype because I have not examined it, and the infold of the caudal process of the specimen was not illustrated by Darby, 1965.

DISTRIBUTION.—Continental shelf off North and South Carolina, Georgia, and Florida (Atlantic and Gulf of Mexico); also, Bahama Islands (Figure 1). Known depth range intertidal to 168 m (Table 1).

DESCRIPTION OF ADULT FEMALE (Figures 18–21).—Carapace ovoid in lateral view, with prominent caudal process and small rostrum with tip projecting ventrally past valve edge (Figure 18, 19a):

Ornamentation: A horizontal rib present above and below central adductor muscle attachments forming alar process on each valve; and additional rib paralleling dorsal border; faint radial riblets along anteroventral margin; additional faint riblets present in vicinity of central adductor muscle attachments and in anterodorsal part of valve (Figure 18); riblets more easily visible on some specimens than on others; some specimens with triangular process in middle of posterodorsal margin (Figure 19a); surface of valves with abundant shallow fossae (Figure 18); anterior margin of rostrum and ventral margin of valve with small scalloped edge (Figure 18); long bristles along anterior and ventral margins and scattered over valve surface.

Infold: Rostral infold of USNM 158003 with 7 bristles paralleling valve edge; rostral infold of USNM 158002 with only 4 bristles on left valve (Figure 19d) and none on right (specimen probably aberrant in having so few rostral bristles); inner edge of incisur with a pair of short bristles; anteroventral infold with 3 or 4 bristles forming row parallel to valve edge; anterior half of ventral infold with 4 bristles parallel to valve edge; ventral infold anterior to caudal process with about 12 bristles forming row prarallel to inner margin of infold; infold of caudal process of right valve with pocket having 5 small bristles along anterior edge (Figure 19f); infold of caudal process of left valve with pocket having along anterior edge a narrow skirt or ruffle having a pleated appearance (Figure 19e); posterior edge of skirt with low processes along upper part becoming longer and forming flat spines at lower part; ventral edge of pocket with 4–6 broad flat spines; left valve with 2 minute bristles just anterior to skirt, 1 near middle, 1 near ventral edge; both valves with several small bristles both dorsal and ventral to anterior edge of pocket and near inner edge of infold; 1 small bristle present on infold near posterior edge of caudal process.

Selvage: Wide lamellar prolongation with marginal fringe present along free margins; fringe longest along rostral and anteroventral margins of valves; prolongation divided at inner end of incisur but not along caudal process.

Central Adductor Muscle Attachment Scars (Figure 19c): Consisting of about 13 individual oval scars.

Size: USNM 158002, length 1.28 mm, height 0.88 mm; USNM 158003, length 1.34 mm, height 0.89 mm; USNM 158193, length 1.30 mm, height 0.90 mm; USNM 158194, length 1.26 mm, height 0.85 mm; USNM 158200, length 1.31 mm, height 0.87 mm; USNM 158618, length 1.11 mm, height 0.79 mm; USNM 158628A, length 1.09 mm, height 0.74 mm.

First Antenna (Figures 19g, 20g): 1st joint with faint medial and lateral spines forming rows. 2nd joint with spines along dorsal margin and distally on lateral surface, and with 2 spinous bristles, 1 dorsal, 1 lateral, 3rd and 4th joints fused; 3rd joint with 3 spinous bristles, 2 dorsal, 1 ventral; 4th joint with 3 spinous bristles, 1 dorsal, 2 ventral. 5th joint with lateral spines forming row at base of sensory bristle; sensory bristle with 2 minute marginal filaments and few spines at tip. 6th joint minute, with short spinous medial bristle. 7th joint: a-bristle spinous, about same length as bristle of 6th joint but slightly stouter, b-bristle about 2½ times the length of a-bristle, bare except for spine at tip; c-bristle about same length as sensory bristle of 5th joint, with 2 minute marginal filaments and spines at tip. 8th joint: d- and e-bristles bare with blunt tips, slightly shorter than c-bristle; f-bristle about two-thirds length of c-bristle, with minute spine at tip; g-bristle about same length as d- and e-bristles, with short-ringed proximal filament with slender spine at tip, and with several minute spines at tip and 1 minute spine just proximal to tip.

Second Antenna (Figures 19h, 20h): Protopodite bare. Endopodite 1-jointed with 4 short anterior bristles (a minute posterior process observed on some limbs (Figure 19h). Exopodite: distal end of 1st joint with distinct small bristle with blunt tip (open?); bristle of 2nd joint reaching past 9th joint, ventral margin with blunt teeth forming row; bristles of joints 3–5 not much longer than bristle of 2nd joint, with blunt teeth forming row along ventral margin; bristles of joints 6–8 long, with natatory hairs; 9th joint with 6 bristles (3 long and 1 medium with natatory hairs, 2 minute, medial, bare).

Mandible (Figures 19i, 21a,b): Coxale endite with 2 pectinate prongs. Basale: medial side near ventral margin with 4 proximal bristles (2 pectinate unringed, 2 ringed; longer of the ringed bristles broken off illustrated limb), 1 small bristle proximal to middle, and 2 bristles near middle; dorsal margin with 3 bristles (1 near middle, 2 distal to middle). 1st endopodial joint with 2 short ventral bristles, and medial spines forming rows. 2nd endopodial joint: dorsal margin with 3 short proximal bristles; medial surface with abundant spines; ventral margin with 2 small distal bristles, and small sclerotized process with minute bristle at base of stout terminal claw; dorsal margin of terminal claw with proximal tooth, serrate margin; tip of terminal claw with small recurved extension (broken off on right limb of USNM 158003 (Figure 21a)). 3rd endopodial joint with stout terminal claw with short curved tip and serrate ventral margin, 3 slender medial bristles near ventral end of base of stout claw, 1 unringed flat bristle (with serrate ventral margin) ventral to stout claw, and 2 short spinous bristles located lateral to stout terminal claw of 2nd joint.

Maxilla (Figures 19j, 21c): Dorsal margin of precoxale and coxale with hairy fringe; dorsal margin of coxale also with terminal bristle. Endite I with 3 stout pectinate bristles and 3 bristles with slender marginal spines; endite II with 2 stout pectinate bristles and 3 bristles with slender marginal spines; endite III with 3 stout pectinate bristles, 2 slender, distal, spinous bristles, and 1 slender, proximal, spinous bristle. Basale with 2 bristles (1 ventral, 1 dorsal). Exopodite small with 2 bristles. 1st endopodial joint with 1 alpha-bristle, 1 beta-bristle, and 1 proximal medial bristle (possibly this bristle is on basale). 2nd endopodial joint with 2 stout pectinate unringed bristles and 4 ringed bristles, mostly with marginal spines.

Fifth Limb (Figures 19k, 21d–f): Endite I with 3 or 4 bristles; endite II with about 5 bristles; endite III obscure, but with about 5 or 6 bristles. Exopodite: 1st joint with 3 stout teeth with seconary teeth followed by 1 smooth tooth and 1 short ringed bristle; outer edge of joint with 1 proximal bristle (Figure 21f). 2nd joint with large 3-lobed tooth; proximal 2 of the lobes with secondary teeth; posterior side of joint with minute bristle near outer corner, and with 2 bristles near proximal lobes (Figure 21e). 3rd joint with 2 bristles on outer lobe (at least 1 with spines) and 3 bristles on inner lobe (2 with spines, 1 denticulate). 4th and 5th joints fused, with total of 4 spinous bristles.

Sixth Limb (Figures 20a, 21g): Endite I with 3 bristles; endites II and III each with 2 bristles; endite IV with 3 bristles; end joint with anterior projection with 3 bristles with short marginal spines followed by 4 hirsute bristles; posterior edge of limb with 2 spinous epipodial bristles.

Seventh Limb (Figures 20b, 21h, i): Each limb with 4 proximal bristles, 2 on each side, and 6 terminal bristles, 3 on each side; each bristle with up to 5 bells and marginal spines; terminus with opposing combs with about 10 teeth on one comb and 4 on other (Figure 21i).

Furca (Figure 20c): Each lamella with 4 stout primary claws followed by 2 small secondary claws; primary claws with teeth along posterior edge; claw 1 with large and small teeth forming groups along posterior edge and with long medial spines forming row near base; secondary claws with posterior spines (proximal of these stout); right lamella with hairs along anterior margin; claws 1 and 2 with few distal anterior hairs; long lateral hairs present along each lamella following claw 6.

Bellonci Organ (Figures 20d, 21j): Elongate, widening near middle, then tapering to either rounded or pointed tip, weak suture may be present near middle.

Eyes (Figures 20d,e, 21j): Medial eye with brown or black pigment; dorsal margin of medial eyes of USNM 158002 and 158003 with several groups of short filaments, which appear to be outgrowths of the medial eye, but origin in doubt. Lateral eyes unpigmented, smaller than medial eye, with 4–6 small ommatidia.

Upper Lip (Figures 20f, 21j): Rounded.

Y-Sclerite (Figures 19b, 20c): Typical for genus.

Brushlike Organ (Figure 19b): 6 minute bristles forming row anterior to Y-Sclerite.

Eggs: USNM 158002, 158194 each with 3 eggs in marsupium; USNM 158003, 158193 each with 4 eggs; USNM 158200 with 2 eggs.

Parasites: USNM 158003 with female and juvenile choniostomatid copepods inside posterodorsal part of carapace. Copepods sent to Dr. Janet Bradford, New Zealand, for study (Bradford, 1980:141). Choniostomatids also present in USNM 158109 and 158199.

DESCRIPTION OF ADULT MALE (Figures 22–24; Plate 1).—Carapace elongate with prominent rostrum and caudal process; incisur forming right-angle (Figure 22; Plate 1a,b); tip of rostrum projecting slightly past valve edge (Figure 23a).

Ornamentation: Posterior half of each valve with 2 horizontal ribs forming alar process (Figure 22); surface with abundant shallow fossae (Figure 22; Plate 1a,b,d); minute pits present between fossae (Plate 1c); bristles present along anterior and ventral margins of valves and scattered over valve surface (Plate 1a–c,f); 1 long and several short bristles present at posterior end of caudal process (Figure 23b).

Infold: Infold of rostrum with 8 long bristles forming row parallel to edge of rostrum (Figure 23a); 2 short bristles present at inner corner of incisur; anterior infold below rostrum with 3 or 4 short bristles; anterior part of ventral margin with 8 or 9 short bristles forming row; posterior part of ventral margin anterior to caudal process with 8 or 9 short bristles. Infold of caudal process of left valve with “pocket” having along the anterior edge a narrow skirt or ruffle having a pleated appearance (Figure 23b,c); posterior edge of skirt with low processes along upper part and broad, flat spines along lower part; ventral edge of pocket with 5 similar broad, flat spines; left valve with 2 minute bristles anterior to skirt, 1 posterior to skirt, and 1 dorsal to skirt. Infold of caudal process of right valve also with pocket, but without skirt or broad, flat spines (Figure 23e); anterior edge of pocket with 4 short bristles; 1 short bristle on infold dorsal to caudal process.

Selvage: Wide lamellar prolongation with marginal fringe present along free margins (Plate 1a,b,e); prolongation divided at inner corner of incisur.

Central Adductor Muscle Attachment Scars (Figure 23d): Consisting of about 15 individual ovoid scars.

Size: USNM 1528551, length of 1.12 mm, height 0.68 mm; USNM 156741, length 1.21 mm, height 0.71 mm.

First Antenna (Figure 23f): 1st joint bare; 2nd joint with hairs on medial surface, spines on lateral surface, and 2 bristles: 1 midbristle on dorsal margin and 1 distal lateral bristle; 2nd joint triangular, with 3 bristles: 1 ventral, 2 dorsal; 3rd joint short with 4 bristles: 1 dorsal, 3 vental; 5th joint small, triangular, wedged ventrally between 4th and 6th joints; sensory bristle of 5th joint with stout proximal part with abundant long filaments; main stem of sensory bristle with minute annulated bristle just distal to base of long filaments and with minute spine at tip; long 6th joint with short, terminal, medial bristle near dorsal margin. Seventh joint: a-bristle about same length as bristle of 6th joint, length about equal to width of joint; b-bristle about 2½ times length of a-bristle, with 2 short proximal filaments, 1 minute spine near middle, and spine at tip; c-bristle very long, with 10 marginal filaments with 2 minute spines at tip, stem with 1 minute spine at tip. Eighth joint: d- and e-bristles bare with blunt tips, slightly longer than b-bristle; f-bristle longer than c-bristle, with 10 marginal filaments, filaments with 2 minute spines at tip, stem with 1 minute spine at tip; g-bristle slightly longer than d- and e-bristles, with 1 marginal filament with minute spine at tip, stem with minute spine at tip and another near tip.

Second Antenna (Figure 23g,h): Protopodite bare. Endopodite 3-jointed: 1st joint short with 5 short anterior bristles, 4 proximal, 1 near middle; 2nd joint elongate with 2 bristles at middle of ventral margin; 3rd joint elongate, reflexed, with 1 proximal and 2 short subterminal bristles, tip with about 4 faint ridges. Exopodite: 1st joint elongate with medial spine just proximal to terminal margin, and second smaller medial spine on terminal margin, vental margin of joint with few hairs; lateral side with spines forming short rows near dorsal margin and longer spines near distal margin; 2nd joint short; ventral margin of bristle of joint with 2 spines followed by shorter spines forming 5 groups, each group with slightly smaller spines than the more proximally located group, bristle reaching distal end of 4th joint; 3rd joint elongate, 4th to 9th joints short; bristles of joints 3–8 long, with natatory hairs; 9th joint with 4 bristles with natatory hairs (3 long, 1 medium) and 1 minute bare bristle; lateral side of joint 2 with long spines forming rows near distal margin; lateral side of joints 3–8 with shorter terminal spines forming row, and with minute basal spines; ventral edge of joints 3–8 may have minute spines.

Mandible (Figure 23i): Coxale endite not observed. Basale: medial surface with numerous spines forming rows and 5 bristles near ventral margin; dorsal margin with 3 midbristles; dorsal and ventral margins and lateral surface near dorsal margin with hairs forming rows. Exopodite: hirsute, reaching about half way up dorsal margin of 1st endopodite joint. Endopodite: 1st joint with long medial hairs and 2 ventral midbristles; 2nd endopodite joint with long medial hairs, lateral spines along distal margin, 3 proximal bristles on dorsal margin, and 6 distal bristles on ventral margin; end joint with long claw and 5 bristles, longest of these about one-half length of claw; claw with short, faint spines along ventral margin.

Maxilla (Figure 23j): Limb very small; endite I with 4 minute unringed bristles; endites II and III obscure on specimen examined, but one of these with a long, ringed, spinous bristle; coxale with long plumose dorsal bristle and dorsal fringe of long hairs (not shown on Figure 23j); basale with 2 distal spinous bristles. Exopodite small with 2 long spinous terminal bristles and 1 short spinous proximal bristle (the latter could be on the distal margin of basale and not part of exopodite). Endopodite: 1st joint with bare, slender, alpha-bristle and stout, plumose, beta-bristle; end joint with 7 bristles; 4 slender, either bare or with short marginal spines, 3 stout with long marginal hairs.

Fifth Limb (Figure 24a): Epipodial appendage with 37 bristles; endite I with 3 short bare bristles; endite II with 4 short bare bristles; endite III with 6 bristles: 5 short, either bare or with few short marginal spines, 1 long with long proximal hairs. Exopodite: 1st joint with 1 ringed, proximal, anterior bristle, 1 ringed, proximal, posterior bristle, and 3 flat, unringed, terminal bristles with marginal hairs; 2nd joint with 1 long unringed proximal bristle, 1 short proximal bristle, and 2 ringed and 2 unringed terminal bristles; outer lobe of 3rd joint with 2 long hirsute bristles, inner lobe with 3 bristles: 2 bare, 1 with long marginal hairs; fused 4th and 5th joints with 4 bare, ringed bristles.

Sixth Limb (Figure 24b): Endites I and II fragmented during dissection; endite III with 2 bristles; endite IV with 3 bristles; end joint with projecting proximal part with 3 spinous bristles and 4 posterior hirsute bristles; 1 limb with 1 epipodial bristle, other limb 2.

Seventh Limb (Figure 24c): Each limb with 8 bristles: 4 proximal with 3 bells, 4 terminal with 5 bells; bristles with short, faint, distal marginal spines; terminus with comb of 3 recurved teeth opposite 2 recurved teeth.

Furca (Figure 24d): Each lamella with 4 stout main claws followed by 2 small secondary claws; claws 1 and 2 with teeth forming lateral and medial row along posterior margin (teeth smaller distally), and with hairs distally along anterior margins and medially near claw base; claw 3 with medial hairs near base; medial hairs present on lamella near base of claw 1; claws 3–6 with teeth along posterior margins; proximal tooth on claws 2–6 longer than others.

Bellonci Organ (Figure 24e,f): Elongate with broad middle part and pointed tip.

Eyes: Medial eye elongate, pigmented in proximal half; dorsal margin with 4 soft bristle-like processes, and distally a lobe with 2 short unringed bristle-like proceses, one of these bifurcate (Figure 24e,f). Lateral eye about same size as medial eye, pigmented, with about 18 divided ommatidia (Figure 24g; only ommatidia along edge illustrated).

Upper Lip (Figure 24h): Rounded without hairs or spines.

Y-Sclerite (Figure 24d): Posterior end bending ventrally, anterior end forming 2 branches.

Heart (Figure 24i): Well-developed, oval, longer than lateral eye.

COMPARISONS.—The carapace of the new species Rutiderma darbyi differs from known species in the study area in having several flat spine-like processes along the ventral edge of “pocket” in the caudal process of the left valve. They are absent on the right valve. The spine-like processes are generally visible when the whole specimen is viewed using transmitted light and an objective lens having a magnification of × 10 or × 20. The spine-like processes are present on juveniles and adults of both sexes.

Rutiderma darbyi Kornicker, 1983

Rutiderma dinochelata— Darby, 1965:28, 56, 57, pl. 13: figs. 1–9, pl. 14: figs. 1–7.—Kornicker. 1975b:65, 74. [Not Kornicker, 1958.]

Rutiderma darbyi Kornicker.—Bradford, 1980:141, fig. 2 [deliberate nomen nudem].

Rutiderma darbyi Kornicker, 1983:2–7, 11–14, 17, 25, 36–47, 62, 85, figs. 18–24. pl. I [female holotype: USNM; type-locality: “Georgia continental shelf, 31°05′N, 80°35′W…26 m”]; 1985:25.

DISTRIBUTION.—Northwest Atlantic: North Carolina to Florida, U.S.A.; Gulf of Mexico: Florida; Bahamas.

HABITAT.—Benthic; intertidal to 168 m; sea grasses; sediment between rocks; surface sediment of tidal flat with Diplanthera; fine to coarse sand; Thalassia bed.

LIFE HISTORY AND ONTOGENY.—Female, male, 2–4 eggs.

STOMACH CONTENTS.—Annelids, diatoms, copepods.

PARASITES.—Choniostomatid copepods (Bradford, 1980; Kornicker, 1983:43).

Rutiderma darbyi Kornicker, 1983

Rutiderma dinochelatum.—Darby, 1965:28, 56, 57, pl. 13: figs. 1–9; pl. 14: figs. 1–7 [not Rutidermata dinochelata Kornicker, 1958].

Rutiderma darbyi Kornicker.—Bradford, 1980:141, fig. 2 [deliberate nomen nudum].

Rutiderma darbyi Kornicker, 1983:2–7, 11–14, 17, 25, 36–47, 62, 85, figs. 18–24; pl. 1.—Grabe, Gibson, and Watkins, 1995:698, table 2.

HOLOTYPE.—USNM 158003, ovigerous female.

TYPE LOCALITY.—Georgia continental shelf, depth 26 m.

MATERIAL.—Crab Cay Cravasse, Sta 95-010: USNM 194582, partly dissected instar IV male in alcohol.

DISTRIBUTION.—Atlantic continental shelf from North Carolina to Florida, Gulf of Mexico continental shelf off Florida, and Bahama Islands in vicinity of San Salvador Island, Andros Island (Kornicker, 1983:38), and in Crab Cay Cravasse, Exuma Islands (herein). Known depth range intertidal to 168 m (Kornicker, 1983:38).

DESCRIPTION OF INSTAR IV MALE.—Carapace similar in shape to that of adult female (Figure 59a).

Ornamentation (Figure 59a,b): Surface with small round separated fossae.

Infold: Infold of caudal process of left valve with serrations along anterior edge of pocket (Figure 59d); serrations and pocket absent on right valve (Figure 59c).

Carapace Size (length, height in mm): USNM 194582, 0.94, 0.70.

Second Antenna: Endopodite elongate, 3-jointed (Figure 59e): 1st joint with 3 short bristles; 2nd joint with 1 or 2 short bristles; 3rd joint with 1 or 2 terminal bristles.

Seventh Limb: Well developed, with 4 proximal bristles (2 on each side), each with 2 bells, and 4 terminal bristles (2 on each side), each with 4 bells; all bristles tapered (juvenile character). Tip with opposing combs with few small teeth.

Furca (Figure 59f): Each lamella with 4 stout claws followed by 2 or 3 secondary claws. USNM 194582 with 2 secondary claws on left limb and 3 on right.

Copulatory Organ (Figure 59f): Consisting of 2 lobes.

SEXUAL DIMORPHISM OF THE FIRST ANTENNAE OF THE CYLINDROLEBERIDINAE.—The c- and f-bristles of the 1st antennae on known species of the Cylindroleberidinae are generally much longer in the adult male than in the adult female and juveniles, and they have many more marginal filaments (Appendix 2). In the female the c- and f-bristles are shorter than the combined length of the joints of the limb, whereas in the male the bristles may be twice the length of the combined joints and as much as one and one-half times the length of the carapace. The c- and f-bristles of juveniles of both sexes resemble those of the adult female, but they may have fewer filaments. The adult male of many described species is unkown. The lengths of the c- and f-bristles of adult males are not presented in most descriptions of the species, but the number of sensory filaments on the bristles often are stated. According to Parker (1998: 105), “halophores [filaments] may be bimodal chemosensory/mechanosensory sensilla,” and are irridescent (Parker, 1995:349), The filaments are probably important in sensing females, and if irridescent, may attract females.

The bristles on the 1st antenna of the adult male Synasterope browni described herein differ from most members of the subfamily in being short and having few filaments (Table 8, Appendix 2). That difference prompted a brief survey of the literature concerning the morphometrics of some of the bristles of the 7th and 8th joints of the 1st antenna of the Cylindroleberidinae (Appendix 2).

Of the 44 adult males listed in Appendix 2, only four have relatively short c- and f-bristles with relatively few marginal filaments. The short bristles are designated “S” in Appendix 2. The c- and f-bristles on at least three of those males do not appear to be significantly different than the bristles on the adult female of the same species. The males having short c- and f-bristles have normal g-bristles, and females of those species have normal c-, f-, and g-bristles (Appendix 2).

The length and number of filaments on the c- and f-bristles on all specimens are clearly related to each other, e.g., a long c-bristle with many filaments is always accompanied by a long f-bristle with many filaments.

The number of filaments on c- and f-bristles varies directly with shell length (Figure 60). For c-bristles, the Pearson correlation coefficient is 0.615, which is significant at the level P<0.01. For f-bristles, the Pearson correlation coefficient is 0.617, which is significant at the level of P<0.01.

Measurements have been made of the lengths of the c- and f-bristles of the males of only six species (Table 8). The few data suggest that lengths of the c- and f-bristles vary directly with shell length.

CORRECTIONS.—Kornicker (1975:439) described the f-bristle of the 8th joint of the 1st antenna of the male Parasterope prolixa Kornicker, 1975, as having 8 filaments and illustrated the right 1st antenna of USNM 139140 with an f-bristle shorter than the g-bristle. The senior author reexamined the slide bearing the illustrated 1st antenna and observed the f-bristle to be folded and bearing about 14 filaments. It is about two-thirds the length of the c-bristle. Kornicker (1976:17), in the description of the f- and g-bristles of the 1st antenna of a male Parasterope beta, incorrectly transposed them. It should have been f-bristle with 29 filaments and g-bristle with 8 filaments. The f- and g-bristles (both broken) also were incorrectly transposed in an adult male of Parasterope kappa (Kornicker, 1976:22).

Synasterope Kornicker, 1975

TYPE SPECIES.—Synasterope implumis Poulsen, 1965, by subsequent designation (Kornicker, 1975:44).

COMPOSITION AND DISTRIBUTION.—See Kornicker and Iliffe (2000:72).

Synasterope browni Kornicker and Iliffe, 2000

Synasterope browni Kornicker and Iliffe, 2000:72–77, figs. 39–44.

HOLOTYPE.—USNM 194469, adult female on slide and in alcohol.

TYPE LOCALITY.—Exuma Sound, depth 96 m.

MATERIAL.—Four Shark Cave, Sta 97-023: USNM 194548, adult male on slide and in alcohol. Mystery Cave, Sta 96-030: USNM 194577, adult male on slide and in alcohol; USNM 194578, A–1 male on slide and in alcohol; USNM 194579, instar I in alcohol.

DISTRIBUTION.—Exuma Sound, depth 96 m; collected herein in Four Shark Cave, South Andros Island, depth 27–33 m. Mystery Cave, Stocking Island, Exuma Cays, depth 50 m.

DESCRIPTION OF ADULT MALE (Figures 61–65, 66a,b).—Carapace oval with posterodorsal margin slightly more oblique than posteroventral margin (Figures 61a, 64f); vertical row of few hairs near posterior end.

Infold: Obscure on slides, but appearing to have relatively few bristles on rostrum and along anteroventral margin (Figure 61b); flap-like posterior bristles present but number obscured (Figure 61c). No processes observed between posteroventral list and valve edge.

Carapace Size (length, height in mm): USNM 194548, 0.66, 0.42; USNM 194577, 0.69, 0.42.

First Antenna (Figures 61d,e, 65a,b): 1st joint with few lateral hairs in distal dorsal corner. 2nd joint with spinous dorsal bristle and without lateral bristle. 3rd and 4th joints fused, triangular; 3rd joint with small bristle on short ventral margin and 6 dorsal bristles (2 single bristles with long spines, 2 paired bristles (lateral with short or long spines, medial with long spines) and 2 paired bristles (lateral with short spines, medial with long spines) on long dorsal margin. 4th joint with terminal, spinous, dorsal bristle and 2 ventral lateral bristles. 5th joint fused to 6th joint and forming small ventral wedge between 4th and 6th joints; bristle of 5th joint unusually stout and with well over 100 filaments (not all shown). 6th joint long, with medial bristle with short spines. 7th joint: a-bristle claw-like, concave dorsally, with proximal dorsal teeth; b-bristle with 3 long dorsal filaments; c-bristle about same length as dorsal margin of joints 2–8, with 6 marginal filaments. 8th joint: d-bristle represented by minute peg (Figure 61e); bare e-bristle about two-thirds length of c-bristle; f-bristle bent dorsally, about two-thirds length of c-bristle, with 5 marginal filaments; g-bristle shorter than c-bristle, with 5 marginal filaments.

Second Antenna (Figure 61f,g): Protopodite with small distomedial bristle. Endopodite 3-jointed; 1st joint short bare; 2nd joint elongate with 3 short bare dorsal bristles near midlength; 3rd joint long, reflexed, with long, bare, proximal filament and pointed tip with few small teeth on inner side. Exopodite: 2nd joint only slightly longer than 3rd joint; bristle of 2nd joint reaching 7th joint, with slender ventral spines; bristles of joints 3 and 4 with slender proximal ventral spines and distal natatory hairs; bristles of joints 5–8 with natatory hairs; 9th joint minute, about one-half width of 8th joint, with 2 bristles (ventral bristle about one-half length of bristle of 8th joint and same length as combined joints 2–9; dorsal bristle shorter); joints 2–8 with few small spines at distal dorsal corner, some joints with minute spines along distal margins, stout basal spines absent.

Mandible (Figures 62, 65e): Coxale endite (Figure 62d,e): ventral branch with 3 or 4 oblique rows of spines and tip with 2 or 3 slender spines; dorsal branch with small main spine; tip obscure; usual bristle near base of ventral branch absent. Basale endite with 3 spinous end bristles, glandular peg, 2 dwarf bristles (proximal about three-quarters length of distal), and 2 trianid bristles with 2 or 3 pairs of spines proximal to terminal pair (terminal pair well developed) (Figure 62b,e). Basale: ventral margin with U-shaped boss near midlength; dorsal margin with 2 long terminal bristles. Exopodite about one-half length of dorsal margin of 1st endopodial joint, with hirsute tip and 2 short subterminal bristles (Figure 62a). 1st endopodial joint with 3 long bristles (2 with long spines near midlength and short proximal and distal spines, 1 with short spines). 2nd endopodial joint (Figure 62a,g): ventral margin with 3 terminal bristles with short marginal spines; dorsal margin with a-, b-, c-, d-, f-, and g-bristles (base of c-bristle slightly stouter than bases of b- and d-bristles), and 1 short bristle proximal to a-bristle; medial surface of joint with 3 cleaning bristles (with short spines) in oblique row near base of c-bristle. 3rd endopodial joint with fairly straight claw with few ventral and dorsal spines, and 5 bristles (not all annulations shown on bristles).

Maxilla (Figure 63a–d): Epipodite obscured. Endite I with 3 bristles (2 long, 1 short); endite II with 3 long bristles (Figure 63a). Basale: medial surface with proximal bristle near dorsal margin and 1 small distal bristle near ventral margin (seen only on left limb of USNM 194548); lateral surface with short proximal bristle near midwidth; ventral margin with long, spinous, terminal bristle. 1st endopodial joint with short alpha-bristle and long beta-bristle. 2nd endopodial joint with long terminal bristle reaching past tip of beta-bristle.

Fifth Limb (Figure 63e): Comb: lateral side with stout spinous exopodial bristle reaching past end of comb; 1 short slender bristle ventral to base of exopodial bristle; 1 pair of bristles and 1 slender bristle closer to ventral margin.

Sixth Limb (Figure 63f,g): Small medial bristle near proximal anterior corner. Anterior margin with slender bristle at upper endite and longer spinous bristle at lower endite. Skirt: anterior end with 3 ventral bristles; lateral flap with slender hirsute anterior bristle; ventral margin with 7 or 8 bristles posterior to midlength.

Seventh Limb (Figures 63h,i, 65c): Proximal group with 4 or 5 bristles (1 or 2 on one side, 3 on other side), each with 2 or 3 bells; distal group with 4 or 5 bristles (2 on one side, 2 or 3 on other side, each with 2 or 3 bells). Terminus with opposing combs with small teeth.

Furca (Figures 63j, 64a,f,g, 65c,f): Each lamella with 8 claws; posterior 3 claws slender, bristle-like, but not ringed (1 oriented backward). Claws 1–7 with teeth along posterior edge; claw 8 with hairs along anterior edge.

Bellonci Organ (Figure 64h): Elongate, broad near middle, with rounded tip.

Eyes: Medial eye bare (Figure 64h). Lateral eye with black pigment and about 15 ommatidia (Figures 61a, 63k, 64f,h, 65a, d).

Lips (Figure 65d,e): Typical for genus, without spines. Copulatory Organ: Extremely long, about one-half length of shell (Figures 61a, 64f), coalesced proximally, divided distally into 2 lobes, each with bifurcate lobate tips; lobes with indistinct bristles near tip (Figures 64d,e, 66a,b).

Posterior of Body (Figures 63j, 64a–c,g, 65c,f): Posterodorsal corner slightly lobate, bare; posterior margin bare.

Gills (Figures 64a, 65c,f): Narrow, number uncertain (2 shown).

Y-Sclerite (Figures 63j, 64a, 65c,f, 66a): Without ventral branch.

DESCRIPTION OF A–1 MALE (Figures 66c–g, 67a–f).—Carapace similar in shape to that of adult female (Figure 66c).

Infold (Figure 66d,e) and Selvage: Similar to that of adult female.

Carapace Size (length, height in mm): USNM 194578, 0.72, 0.39.

First Antenna (Figure 66f,g): 1st joint with lateral hairs in distal dorsal corner and distal medial hairs near midheight. 2nd joint with spinous dorsal bristle and without lateral bristle. 3rd and 4th joints fused; 3rd joint with small bristle on ventral margin and 6 dorsal bristles (2 single bristles with long spines, and 2 pairs of bristles either bare or with indistinct short spines). 4th joint with dorsal bristle with short spines and bare ventral bristle. 5th joint with weak sutures separating joint from 4th and 6th joints; sensory bristle with short proximal filament and 6 long terminal filaments. 6th joint long, with long medial bristle. 7th joint: a-bristle claw-like, with concave dorsal margin and proximal dorsal teeth; b-bristle with 3 long dorsal filaments; c-bristle with 4 filaments at midlength and 1 subterminal. 8th joint: d-bristle represented by minute papilla (not shown on illustration); bare e-bristle about one-half length of c- bristle; f-bristle bent dorsally, about two-thirds length of c-bristle, with 4 marginal filaments; g-bristle shorter than c-bristle, with 5 marginal filaments. Illustrated left limb of USNM 194578 shows filaments of sensory bristle of adult male within.

Second Antenna: Protopodite and endopodite similar to those of adult male. Endopodite 3-jointed (Figure 66h): 1st joint bare; 2nd joint elongate with 2 short distal bristles; 3rd joint elongate with long, bare, proximal filament and pointed tip. Illustrated detail of tip of endopodite of USNM 194578 shows pointed tip with few small teeth of endopodite of adult male within.

Mandible: Coxale endite broken off. Remainder of limb similar to that of adult male.

Maxilla (Figure 67a,b): Epipodite triangular. Endite I with 3 bristles (2 long, 1 short); endite II with 3 long bristles. Basale with short proximal medial bristle near dorsal margin or at midwidth; ventral margin with short proximal bristle, none or 1 short indistinct distal bristle, and long terminal bristle; proximal lateral bristle obscured. Endopodite: 1st joint with short alpha- and long beta-bristle; 2nd joint with terminal bristle longer than beta-bristle of 1st joint.

Fifth Limb: Similar to that of adult male.

Sixth Limb: In general, similar to that of adult male.

Seventh Limb: Proximal group with 5 tapered bristles (2 on one side, 3 on other), each with 1 to 3 bells; distal group with 5 slightly tapered bristles (2 on one side, 3 on other), each with 1 or 2 bells. Terminus with opposing combs with few small teeth.

Furca (Figure 67 c,d,f): Similar to that of adult male.

Bellonci Organ: Not observed.

Eyes: Medial eye not observed. Lateral eye with black pigment and obscured amber-colored ommatidia (Figure 66c).

Lips (Figure 67e): Similar to those of adult male.

Copulatory Organ (Figure 67f): Large with 2 lobes at anterior tip, without visible internal sclerites.

Posterior of Body (Figure 61d): Posterodorsal corner slightly lobate and with spines; posterior ventral to posterior end of girdle hirsute.

Gills: Narrow.

Y-Sclerite (Figure 61d): Similar to that of adult male; anterior tip with small hook-like ventral sclerite.

DESCRIPTION OF INSTAR I (sex unknown) (Figure 61g–o).—Carapace less elongate than that adult female (Figure 67g); dorsal edge of caudal process extending onto lateral surface of valve (Figure 67h).

Infold and Selvage: Not examined.

Carapace Size (length, height in mm): USNM 194579, 0.44, 0.28.

First Antenna (Figure 67i): 1st, 2nd, and 4th joints bare. 3rd joint with long, spinous, dorsal bristle and small, bare, ventral bristle. Sensory bristle of 5th joint without filaments. 6th joint with medial bristle. 7th joint: a-bristle claw-like, b- and c- bristles bare. 8th joint: d-bristle absent; e-bristle about same length as c-bristle, bare, distal part filamentous, indistinct; fand g-bristles bare.

Second Antenna (Figure 67j,k): Protopodite with small distal medial bristle. Endopodite weakly 3-jointed, with long terminal filament. Exopodite 9-jointed: bristle of 2nd joint reaching 7th joint, with slender ventral spines; bristles of joints 3–8 with distal natatory hairs (some bristles with proximal ventral spines); 9th joint with 2 bristles (dorsal bristle short, bare, ventral bristle longer and with natatory hairs); joints 3–7 with row of minute terminal spines; joints 6–8 each with indistinct, small, basal spine; 9th joint with small lateral spine (Figure 67k). (Basal spines not observed on exopodites of adults.)



Mandible (Figure 68a): Coxale endite broken off. Basale: endite with 1 trianid bristles with 3 pairs of spines proximal to terminal pair, 2 dwarf bristles, 1 glandular peg, and 2 spinous end-bristles; dorsal margin with 2 long terminal bristles. Exopodite almost as long as dorsal margin of 1st endopodial joint, with 2 small terminal bristles. 1st endopodial joint with 2 long ventral bristles (one with long spines); 2nd endopodial joint: dorsal margin with 2 stout bristles (possibly c- and d-bristles); lateral side near dorsal margin with long lateral bristle (possibly f-bristle) between those 2 stout bristles; medial side near dorsal margin with 2 short cleaning bristles adjacent to proximal stout c?-bristle, and 1 long bristle (possibly g-bristle) just distal to distal stout d?-bristle. 3rd endopodial joint with stout claw-like bristle and 4 slender ringed bristles.

Maxilla (Figure 68b): Epipodite obscured. Endites I and II each with 2 long bristles. Basale with short medial bristle near midlength and midheight and long, ventral, terminal bristle.

1st endopodial joint with short alpha-bristle and long beta-bristle. 2nd endopodial joint with long terminal bristle extending past beta-bristle.

Fifth Limb (Figures 67l, 68c): Well developed but with few ventral bristles on comb (Figure 67l).

Sixth Limb (Figures 67m,n, 68c): With stout bristle on posterior tip of skirt, but no endite or ventral bristles.

Seventh Limb: Absent.

Furca (Figure 68c,f): Each lamella with 3 claws: claw 1 separated from lamella by suture, remaining claws fused to lamella. Claws 1 and 2 with stout teeth along posterior edge (distal teeth longer); claw 3 with hairs or slender spines along posterior edge; claw 1 with distal hairs along anterior edge. Right lamella anterior to left by width of base of claw 1.

Bellonci Organ (Figure 67o): Elongate, with rounded tip.

Eyes: Lateral eye with black pigment and small obscured ommatidia (at least 10) (Figure 67g,j). Medial eye present (Figure 67o).

Lips (Figure 68d): Similar to those of A-1 male.

Copulatory Organ: Absent.

Posterior of Body (Figure 68c,e,f): Posterodorsal corner with stout spines (not shown on Figure 68f).

Gills (Figure 68e): Seven narrow gills on each side of body. Attachment of gills typical for genus.

Y-Sclerite (Figure 68c): Fused to girdle.

DISTRIBUTION.—Three species are referred to this genus: A. americana (Müller, 1890), A. antyx Kornicker, 1981, and A. cubensis (Lalana and Kornicker, 1997). The genus is widespread in world oceans; depth ranges from surface to 53.5 m (Kornicker, 1981:167).