Eusarsiella phrix Kornicker 1996

Eusarsiella phrix

ETYMOLOGY.—From the Greek phrix (a ruffling of a smooth surface).

HOLOTYPE.—Instar IV (A–l) female on slide and in alcohol, QM W20743. (Specimen with appendages of adult visible inside its appendages.)

TYPE LOCALITY.—Calliope River and Auckland Creek area, near Gladstone, Queensland, Australia.

PARATYPES.—None.

DISTRIBUTION.—Collected only at type locality.

DESCRIPTION OF INSTAR IV FEMALE (Figures 36, 37).—Carapace oval in lateral view, with long slender posteroventral caudal process (Figure 36a–c).

Ornamentation (Figure 36a–c): Thin flange extends past valve edge along margins except on caudal process where ends of ventral and posterior flanges terminate on outer surface near midlength of process (dashed line just within outer margin of valve in Figure 36a represents valve edge). Flange along dorsal margin with large triangular process just posterior to midlength and 3 or 4 smaller processes anterior to it; flange along posterior margin with triangular process at midheight. Alate rib extends from valve near midlength and midheight (in vicinity of central adductor muscle attachments) to posterodorsal corner where it reaches past valve edge (Figure 36a). A second alate rib, broadest in vicinity of central adductor muscle attachments, continues as narrow indistinct rib almost to anterior valve margin (Figure 36a); surface of posterior parts of both alate processes with minute U-shaped scales (Figure 36a,b); ribs of left and right valves differ only slightly in shape. Inner side of flange along anterior and ventral margins bears numerous long bristles (Figure 36c), some bristles with stout proximal part. Tip of caudal process with slender bristle at both ventral and dorsal corners (Figure 36c); outer surface of valves smooth, with very few bristles, and without gel-like coating.

Infold: Anterior infold with minute bristle near valve midheight. Infold of caudal process with 5 small spine-like bristles (Figure 36c); posterior infold with 2 setal bristles dorsal to caudal process (Figure 36c); 1 or 2 minute bristles present just dorsal to caudal process and ventral to setal bristles; inner margin of infold poorly defined.

Carapace Size (length (L), height (H), in mm): QM W20743 (holotype), right valve with body removed: L = 1.95 including caudal process, H = 1.05 including flanges.

First Antenna (Figure 36d): 1st joint bare. 2nd joint with dorsal bristle with indistinct spines. 3rd joint fused to 4th, with 2 bristles (1 ventral small bare, 1 dorsal longer with few indistinct spines); 4th joint with 3 bristles (1 dorsal with spines, 2 ventral bare). Ventral bristle of 5th joint long with minute proximal filament and minute terminal papilla (only proximal part of bristle shown). 6th joint fused to 5th joint, with short medial bristle near dorsal margin. 7th joint: a-bristle about same length as bristle of 6th joint, with slender subterminal hair; b-bristle about 3 times length of a-bristle, with minute terminal papilla; c-bristle same length as bristle of 5th joint, with minute proximal filament and minute terminal papilla (only proximal part of bristle shown). 8th joint (bristles not shown): d- and e-bristles very slightly shorter than c-bristle, bare with blunt tips; f-bristle about same length as c-bristle, with minute terminal papilla; g-bristle same length as c-bristle, with minute terminal papilla.

Second Antenna: Protopodite bare (Figure 36e). Endopodite 1-jointed, with 1 or 2 proximal ringed anterior bristles and minute spine-like terminal bristle (Figure 36e). Exopodite: 1st joint with minute terminal medial curved tubular bristle; bristles of joints 2–8 with natatory hairs, no spines; 9th joint with 2 bristles (1 short dorsal, 1 long ventral) with natatory hairs; joints 2–8 with up to 10 indistinct medial spines along distal edges.

Mandible (Figure 37a): Part of coxale containing endite broken off both limbs of holotype; coxale with slender ventral spines. Basale: ventral margin with 5 or 6 small bristles (2 or 3 proximal and 1 distal medial, 2 distal lateral); dorsal margin with 1 short bristle distal to middle and 2 short ringed subterminal bristles. Exopodite absent. 1st endopodial joint with spines (on medial surface, ventral margin, and terminally on dorsal margin), stout ventral claw with short row of minute spines proximally on dorsal margin, and minute medial bristle near base of claw. 2nd endopodial joint with small dorsal bristle and stout ventral claw. 3rd endopodial joint with stout terminal claw and 3 minute bristles (2 ventral, 1 dorsal).

Maxilla (Figure 37b): Endites I and II (endite II bristles not shown) each with 6 bristles; endite III with 4 bristles (not shown). Coxale with short dorsal bristle on left limb but none on right limb (Figure 37b and with fringe of dorsal hairs. Basale without bristles. Exopodite with 3 bristles (1 long, 2 short). Endopodite: 1st joint with spines along anterior margin and spinous and pectinate alpha- and beta-bristles; 2nd joint with 2 small a-bristles, 1 small c-bristle, and 5 stout pectinate end bristles (middle bristle shorter, anterior bristle ringed distally).

Fifth Limb (Figure 36f): Epipodite with about 34 bristles. Single endite with short bristle. Exopodite: 1st joint with 3 bristles; joints 2–5 fused, with total of 8 or 9 bristles (interpretation: 2nd joint with 3 bristles; 3rd joint with 3 or 4 bristles (2 long plus none or plus 1 minute on inner lobe, and 1 on outer lobe); fused 4th and 5th joints with total of 2 bristles).

Sixth Limb (Figure 37c): Single endite with 2 bristles (1 short medial, 1 longer terminal). End joint with 14 spinous ringed bristles followed by space and 2 broad plumose posterior bristles.

Seventh Limb (Figure 37d): Proximal group with 11 tapered bristles (juvenile character), 5 on one side, 6 on the other, each with single bell; terminal group with 4 tapered bristles, 2 on each side, each with 2 bells; all bristles without marginal spines. Tip with small opposing combs, each with few minute teeth.

Furca (Figure 37e): Each lamella with 5 claws; claw 1 nonarticulated; claws 1–4 with teeth along posterior edge, some teeth longer than others, but none longer than width of claw base (some of long teeth shown in Figure 37e); left lamella with few spines following last claw; right lamella anterior to left lamella by width of base of claw 1.

Bellonci Organ (Figure 37f–i): Tapering to narrow tip (similar to that of Eusarsiella saengeri).

Eyes: Medial eye with brown area (Figure 37f–i). Lateral eye: left side of holotype with triangular process with single oval near tip (similar to process of E. tryx) (Figure 37g), but right side with indistinct eye with light brown pigmented area containing a few minute cells (eye somewhat similar to those of E. saengeri but less distinct) (Figure 37f).

Upper Lip (Figure 37j): Single bare lobe.

Genitalia: Absent.

Posterior of Body: Evenly rounded, bare.

Y-Sclerite (Figure 37k): Similar to that of E. tryx.

COMPARISONS.—The carapace of E. phrix differs from those of E. tryx and E. saengeri in having an alate process at midlength and midheight in addition to the posterodorsal alate process present on all three species. The alate processes on E. phrix resemble those of Eusarsiella disparalis (Darby, 1965) and E. dispar Kornicker, 1986a, collected in the Atlantic Ocean and Gulf of Mexico in the vicinity of North America, but the first antenna of E. phrix differs from those species in having a ventral bristle on the third joint.

Eurypylus Brady, 1869

TYPE SPECIES.—Eurypylus petrosus Brady, 1869:141, by monotypy.

COMPOSITION.—This genus has eight species including three (two described herein) from Australia.

DISTRIBUTION.—Continental shelf off Georgia, North America; mangrove area in vicinity of Tanzania, East Africa; Cape Verde Islands off West Africa; shallow water in vicinity of Singapore; in vicinity of Mayotte and Glorioso Islands, Indian Ocean; Lizard Island lagoon, Australia; and Darwin, sta 304, and Calliope River and Auckland Creek area, Australia, herein.