Philomedes bonneti Kornicker & Caraion 1977

Philomedes bonneti

HOLOTYPE.—“Grigore Antipa” 288, ovigerous female, length 1.99 mm, right valve and some appendages in alcohol, remaining appendages on 2 slides; right valve gold-plated.

TYPE-LOCALITY.—Station X046.

ETYMOLOGY.—The species is named for Dr. Marc Bonnet, leader of the expedition aboard Thalassa.

ALLOTYPE.—“Gigore Antipa” 289, adult male, length 2.15 mm, from same station as holotype.

DESCRIPTION OF FEMALE (Figures 6–8; Plates 1–4).—Carapace not calcified, with slightly convex dorsal margin, evenly rounded anterodorsal and posterodorsal corners, almost straight anterior and posterior margins except for small caudal process (Figures 6, 7a–d; Plates 1–3); ventral margin convex with small swelling near anterior end; distal margin of rostrum straight with minute protuberance on posterior corner (Figures 6, 7a; Plate 1c,d); incisur broad with rounded inner end (Figures 6, 7a).

Ornamentation (Figure 7e; Plates 1b–f): Surface smooth with widely scattered bristles with broad base and shorter bristles without broad base; bristles form row along ventral margin and caudal process; edge of caudal process with 6–10 minute digitations (Figure 7c; Plate 2b,c,f).

Infold (Figure 7a,c,d; Plates 2d–f, 3): Broad along anterior and ventral margins and narrow along posterior margin dorsal to caudal process; infold on rostrum with 26 bristles, mostly spinous with bifurcate tips; 1 small bristle present on infold posterior to inner end of incisur; anteroventral part of infold with about 15 striae and 17 spinous bristles; infold along ventral margin bare; list paralleling inner margin of posteroventral and posterior infold with about 43 small bristles in groups of 1 to 6 bristles; “pocket” present in infold of caudal process; anterior margin of pocket with 5 or 6 small bristles; outer edge of caudal process with 3 minute bristles; posteroventral infold anterior to caudal process with 2 or 3 bristles near middle.

Selvage (Figure 7a; Plates 1a,c,d, 2d, 3): Lamellar prolongation striate, fringed; anteroventral prolongation with additional long hairs with bases on lateral side.

Central Muscle Attachment Scars: Consisting of about 15 individual oval scars (Figure 6).

Size: Holotype, length 1.99 mm, height 1.43 mm.

First Antenna (Figure 7f–h): 1st joint: medial hairs and spines. 2nd joint: short spines forming 7 or 8 rows on lateral surface near dorsal margin, and short row of stouter spines forming single row on lateral surface near terminal dorsal corner (Figure 7h); 3 bristles (1 ventral, 1 dorsal, 1 lateral), each with long middle and short distal spines. 3rd joint: 1 ventral bristle with short marginal spines and 3 dorsal bristles (2 long with long middle and short distal spines, 1 short with short marginal spines). 4th joint: 1 dorsal bristle with long middle and short distal spines, and 4 ventral bristles (2 long, 1 medium, 1 short), all with long middle and short distal spines. 5th joint: sensory bristle with 5 short proximal filaments and 5 short terminal filaments including stem. 6th joint: medial bristle about two-thirds length of a-bristle, with long middle and short distal spines. 7th joint: a-bristle with long middle and short distal spines; b-bristle about twice length of a-bristle, with 1 short proximal filament and 3 short terminal filaments; c-bristle about same length as sensory bristle of 5th joint, with 3–5 short proximal filaments and 5 short terminal filaments including tip. 8th joint: d- and e-bristles bare, about same length as c-bristle; f-bristle about same length as c-bristle, with 4 short proximal filaments and 4 short terminal filaments including stem; g-bristle about same length as c-bristle, with 3 short proximal filaments and 5 short terminal filaments including stem.

Second Antenna (Figure 7i): Protopodite bare. Endopodite 2-jointed: 1st joint with 5 short, bare, proximal bristles, and 1 short distal bristle with few short hairs; 2nd joint with 1 recurved bare terminal bristle and 3 ventral bristles (proximal of these long, with long middle and short distal spines; middle bristle short with short marginal spines; distal bristle with few long middle spines and short distal spines). Exopodite: 1st joint with short medial spine; joints 2–8 with short spines forming row near terminal margin and short basal spines increasing in length on distal joints; basal spine on joint 8 one-half to three-fourths length of ventral margin of 9th joint; bristle of joint 2 reaching well past 9th joint and with 2 minute ventral spines near middle of bristle; bristles of joints 3–5 bare, slightly longer than bristle of 2nd joint; bristles of joints 6–8 and 4 long bristles of 9th joint broken, with natatory hairs near tip of stump; 9th joint with 2 unbroken, short, dorsal bristles with long middle and short distal hairs, and 1 unbroken, very short bare dorsal bristle; 9th joint without lateral spine.

Mandible (Figure 7j): Coxale endite bifurcate, spinous, with minute bristle near base. Basale: medial side with 6 proximal bristles near ventral margin (3 unringed, pectinate, 3 ringed, with long middle and short distal spines); lateral side with 5 bristles forming row near ventral margin, each with long middle and short distal spines; ventral margin with 3 distal bristles with long middle and short distal spines; dorsal margin with 3 bristles in addition to 2 terminal bristles, all with long middle spines, some with very short distal spines or without distal spines. Exopodite and endopodite similar to those of Philomedes lilljeborgii (Sars, 1865) (see Skogsberg, 1920: fig. 11).

Maxilla (Figure 8a–c): Similar to that of P. lilljeborgii (see Skogsberg, 1920:408). Distal margin of basale with 4 bristles of which 2 form pair near anterior corner.

Fifth Limb: Similar to that of Philomedes globosa (Liljeborg, 1853) [=Philomedes brenda (Baird, 1850), Sylvester-Bradley, 1950] (see Skogsberg, 1920: 388) and P. lilljeborgii (see Skogsberg, 1920:407, fig. 12).

Sixth Limb (Figure 8d): Similar to that of P. globosa (see Skogsberg, 1920:390); limbs of holotype with 24 or 25 bristles on end joint.

Seventh Limb (Figure 8e): Similar to that of P. lilljeborgii (see Skogsberg, 1920:407, 408, figs. 13, 14), except with only 4 proximal bristles, 2 on each side.

Furca: Similar to that of P. lilljeborgii (see Skogsberg, 1920:409, fig. 15).

Rod-shaped Organ: Elongate, 1-jointed with rounded tip (Figure 8f).

Eyes: Medial eye bare, eye of holotype without black pigment (Figure 8f); lateral eye weak, difficult to see, with numerous minute oval bodies (cells?) (Figure 8f).

Upper Lip: Helmet-shaped, hirsute, with several anterior processes (Figure 8f).

Anterior and Posterior of Body: Rounded knob present between medial eye and upper lip (Figure 8f). Posterior of body just dorsal to furca hirsute.

Y-Sclerite: Normal for genus (Figure 8g).

Genitalia: Small oval structure anterior to anus (Figure 8g).

Eggs: Holotype with 8 eggs in marsupium.

DESCRIPTION OF MALE (Figures 9, 10; Plate 4).—Carapace slightly longer than that of female but not as high (Figure 9); incisur more open than that of female; protuberances on posterior corner of rostrum and along anteroventral margin absent.

Ornamentation: Similar to that of female carapace except with more long bristles with broad bases present near posterior of each valve.

Infold: Similar to that of female.

Size: Allotype, length 2.15 mm, height 1.16 mm.

First Antenna (Figure 10a): 1st joint: bare. 2nd joint: spines forming rows near distal dorsal and ventral margins and near terminal margin of medial surface; lateral surface with long hairs forming rows distally; 3 bristles (1 ventral with long middle and short distal spines; 1 dorsal and 1 medial, both with only short marginal spines). 3rd joint: short spines forming rows on medial surface and 4 bristles (3 dorsal, I very short, with short marginal spines, 2 longer with long middle and short distal spines; and 1 ventral with long middle and short distal spines, the base of this bristle actually on medial side of terminal margin). 4th joint: 5 bristles (1 dorsal with long middle and short distal spines, and 4 ventral bristles with bases on medial surface; outer and inner bristles shorter than middle bristles and with long middle and short distal spines; long middle bristles with only short marginal spines). 5th joint: minute, triangular; sensory bristle with abundant filaments along broad proximal part and 5 terminal filaments. 6th joint: medial bristle with base near dorsal margin and with long middle and short distal spines. 7th joint: a-bristle about same length as bristle of 6th joint, with short marginal spines; b-bristle less than twice length of a-bristle, with 3 marginal and 4 terminal filaments including stem; c-bristle extremely long, with 12 or 13 marginal filaments. 8th joint: d- and e-bristles bare with blunt tips; d-bristle about 3 times length of a-bristle; e-bristle about 4 times length of a-bristle; f-bristle same length as c-bristle, with 12 marginal filaments; g-bristle slightly longer than b-bristle, with 3 marginal and 5 terminal filaments including stem.

Second Antenna: Protopodite bare. Endopodite 3-jointed (Figure 10b,c): 1st joint with 5 short, bare, proximal bristles and 1 short spinous distal bristle; 2nd joint elongate with 3 spinous bristles at middle of ventral margin; 3rd joint elongate, reflexed on 2nd, with 2 small subterminal bristles and tip with about 5 toothed ridges. Exopodite: 1st joint with short medial spine; 2nd joint with spines forming row along distal margin and bare ventral bristle reaching 5th joint; 3rd joint longer than 2nd, with spines forming row along distal margin; bristles of joints 3–8 and long bristles of 9th joint with natatory hairs; joints 3–8 with basal spines increasing in length on distal joints; basal spine on joint 8 about one-half length of joint 9; joint 9 and its bristles obscure on appendage examined.

Mandible (Figure 10d,e): Coxale endite small, bifurcate, with minute bristle near base (Figure 10d). Basale: medial side with 5 proximal bristles (3 non-annulate, 2 annulate), all with slender marginal spines (not pectinate); medial side near middle with 1 slender bristle with long middle and short distal spines; lateral side with 4 bristles forming row almost on ventral margin, all with long middle and short distal spines; ventral margin with 2 distal bristles with long middle and short distal spines; dorsal margin with 3 bristles in addition to 2 terminal bristles, all with long middle spines, lateral bristle of terminal pair about same length as exopodite; medial surface of basale spinous. Exopodite similar to that of female except both bristles with only short marginal spines. Endopodite similar to that of female, except proximal group of bristles on dorsal margin of 2nd joint with only 4 bristles, and bristles in distal group with only short marginal spines.

Maxilla: Appendage slightly smaller than that of female; distribution of bristles also similar except that most are hirsute.

Fifth Limb (Figure 10f): Similar to that of Philomedes globosa (Liljeborg, 1853) described by Skogsberg (1920:391, fig. 15).

Sixth Limb: Endite I with 1 medial and 2 terminal bristles; endite II with 1 medial and 3 terminal bristles; endites III and IV with 1 medial and 8 terminal bristles; end joint with 18 bristles; 3 hirsute epipodial bristles present; most bristles on appendage with long hairs either proximal or all along margin except near tip.

Seventh Limb, Rod-shaped Organ, Upper Lip (Figure 10h), Anterior, Posterior, Y-Sclerite: Similar to that of female.

Furca: Similar to that of female except with only 9 claws.

Eyes: Medial eye similar to that of female (Figure 10g); lateral eye larger than medial eye, with about 29 ommatidia (Figure 10g).

Heart: Well-developed, tapering slightly towards posterior.

Copulatory Organ: Elongate with 2 or 3 lobes at tip (Figure 10i).

COMPARISONS.—The female of the new species, P. bonneti, closely resembles the female of Philomedes lilljeborgii (Sars, 1865) described by Skogsberg (1920:402), but differs from that species as follows: posterior edge of caudal process with minute digitations; dorsal margin of mandibular basale with 5 instead of 6 or 7 bristles; 7th limb with 9 instead of 10 or 11 bristles.