Rutiderma dinochelatum Kornicker 1958

Rutiderma dinochelatum Kornicker, 1958

Rutiderma (Rutiderma) dinochelata Kornicker. 1958:224, 236–238, figs. 46:8A,B, 57A–F, 58A–D, 86B.F,J [female holotype: USNM; type-locality: “Bimini area…Great Bahama Bank…bottom…1–20 meters”].

Philomedes lomae.—Kornicker, 1958:233, 234. figs. 46:7A,B. 52:A–E, 53:A–D, 86:A,E,I.—Poulsen, 1965:15,17 [recognizes specimens as male Rutiderma]. [Not Juday. 1907.]

Rutiderma (Rutiderma) donochelata.—Kornicker. 1958:297, fig. 86B,F,J [misspelling].

Rutiderma dinochelata.—Hartmann, 1965:328 [mentions].—McKenzie, 1965:66 [compares to R. judayi].—Poulsen. 1965:7, 8, 17, 18, 43.—Kornicker. 1969:110; 1975a:43 [compares to R. leloeuffi]; 1975b:675.

Rutiderma dinochelatum.—Kornicker. 1981b:8 [compares to R. sterreri]; 1983:11–14, 25–28, 70. figs. 10, 11.

Not Rutiderma dinochelata— Darby, 1965:28, 56, 57, pl. 13: figs. 1–9, pl. 14: figs. 1–7 [= R. darbyi Kornicker. 1983].—Kornicker. 1975b:65, 74.

DISTRIBUTION.—Northwest Atlantic: Bahama Islands: Bimini and Andros Islands.

HABITAT.—Benthic, intertidal–20 m; temperature: about 29°C; salinity: 31–42‰.

LIFE HISTORY AND ONTOGENY.—Female, juvenile female.

BIOLOGY.—Response to light (Kornicker, 1958:224).

Rutiderma dinochelatum Kornicker, 1958

Rutiderma (Rutiderma) dinochelata Kornicker, 1958:236, figs. 46:8A-B, 57A-F, 58A-D, 86B,F,J.

Philomedes lomae.—Kornicker, 1958:233, figs. 46:7A-B, 52A-E, 53A-D, 86A,E,I.—Poulsen, 1965:17 [recognized specimens as male Rutiderma].

Rutiderma dinochelata.—Poulsen, 1965:17.—McKenzie, 1965:66.—Kornicker, 1975:65, 74.

Rutiderma dinochelatum.—Kornicker, 1981a:8. Not Rutiderma dinochelata.—Darby, 1965:28, pl. 13, 14 [=R. darbyi, new species, herein].

HOLOTYPE.—USNM 122907, adult female, dry specimen softened and now in alcohol, partly dissected.

TYPE-LOCALITY.—Bimini, Bahamas, sta 57.

MATERIAL.—Bahamas: holotype; USNM 158525, paratype, 1 juvenile female, Bimini, sta 247; USNM 158620, 2 juveniles, Andros Island, sta 91.

DISTRIBUTION.—Bahama Islands (Figure 2; Table 1).

SUPPLEMENTARY DESCRIPTION OF HOLOTYPE (Figure 11a–f).—Carapace with slightly overhanging rostrum and projecting caudal process. (Carapace of adult female paratype is illustrated in Figure 10).

Ornamentation: Carapace with well-developed horizontal and radial ribs (Kornicker, 1958, fig. 46:8A,B [on 8B the caudal process has been cropped off the photograph]). Small process in middle of posterior margin of left valve. Surface with abundant shallow fossae.

Infold: Rostral infold with 8 bristles in row parallel to anterior margin, and 1 small bristle near inner edge of incisur; 1 small bristle near middle of infold ventral to incisur (Figure 11a).

Size: Length 1.22 mm, height 0.87 mm (from Kornicker, 1958:237). Present dimensions: length 1.15 mm, height 0.82 mm.

First Antenna: 2nd joint with 2 bristles, 1 dorsal, 1 lateral; 3rd and 4th joints fused; 3rd joint with 3 bristles, 1 ventral, 2 dorsal; 4th joint with 3 bristles, 2 ventral, 1 dorsal (Figure 11b).

Second Antenna: Endopodite 1-jointed, with 4 short anterior bristles (Figure 11c). Exopodite: bristles of joints 2–5 without natatory hairs; long bristles of joints 6–9 with natatory hairs.

Mandible (Figure 11 d): Terminal claw of 2nd endopodial joint with rounded tip neither protracted nor upturned; claw with proximal tooth on inner margin; terminal claw of 3rd endopodial joint with truncate tip.

Furca (Figure 11e): Each lamella with 4 stout pectinate claws followed by 2 weaker spinous claws; claw 1 of right lamella anterior to claw 1 of left lamella.

Bellonci Organ (Figure 11f): Broadening in middle, then tapering to pointed tip. (Broad midbulge on illustrated organ probably partly result of twisting of organ.)

SUPPLEMENTARY DESCRIPTION OF JUVENILE FEMALE.—Instar III?, from Bimini, USNM 158525 (Figure 11g–l). Similar in shape to that of adult female, but softened specimen distorted. Small process near middle of posterior edge of left valve.

Infold: Rostral infold obscure but with at least 3 bristles (Figure 11g). List of caudal process forming about 45° angle with ventral margin of valve, with 2 small bristles, 1 at each end; 1 small bristle in pocket between list and posterior end of caudal process (Figure 11h,i); posterior infold with 1 small bristle dorsal to caudal process; ventral margin anterior to caudal process with several bristles.

Size: USNM 158525, length 0.79 mm, height 0.54 mm.

First Antenna (Figure 11j): 1st joint bare. 2nd joint with 2 bristles, 1 dorsal, 1 lateral. 3rd and 4th joints fused; 3rd joint with 2 or 3 bristles, 1 ventral, 1 or 2 dorsal; 4th joint with 2 bristles, 1 ventral, 1 dorsal. Sensory bristle of 5th joint with 2 minute marginal filaments. 6th joint minute, fused to 5th, with 1 short medial bristle. 7th joint: a-bristle about one-third longer than bristle of 6th joint; b-bristle about same length as a-bristle, with minute filament near middle; c-bristle same length as sensory bristle of 5th joint, with 2 minute marginal filaments. 8th joint: d- and e- bristles bare with blunt tips, about three-fourths as long as c-bristle; f-bristle slightly longer than d-bristle; g-bristle about same length as c-bristle, with fairly long proximal filament and minute distal filament.

Second Antenna: Protopodite bare. Endopodite 1-jointed, with 2 small anterior bristles and 1 minute posterior process (Figure 11k). Exopodite: distal medial margin of elongate 1st joint with minute, straight, tubular bristle; bristles of joint 2–8 short with row of blunt, closely spaced, spines along ventral margin, no natatory hairs; 9th joint with 4 short bristles (ventral of these longer than others and with blunt ventral spines); joints 3–8 with slender spines forming row along distal margin, no basal spines.

Mandible (Figure 11l): Terminal claws of 2nd and 3rd endopodial joints similar to those of adult. Except for having only 1 lateral bristle, bristles of 3rd endopodial joint similar to those of adult female.

Maxilla, Fifth and Sixth Limbs: Well developed. Seventh Limb: Elongate, without bristles; tip rounded bare.

Furca: Similar to that of adult female, with 4 stout claws followed by 2 weaker claws.

Bellonci Organ: Similar to that of female but with middle part not as broad and tip less pointed. Tip similar to organ illustrated by Kornicker (1958, fig. 57D).