Eusarsiella dornellasae (Kornicker & Caraion 1978)

Sarsiella dornellasae

HOLOTYPE.—USNM 156654, ovigerous female on slides and in alcohol.

TYPE-LOCALITY.—Station X068.

ETYMOLOGY.—The species is named for Lilia Pinto de Ornellas, Porto-Alegre, Brazil.

ALLOTYPE.—[USNM 156653], adult male from same sample as holotype.

PARATYPES.—“Grigore Antipa” 468, 1 ovigerous female from station X068; USNM 157116, 3 ovigerous females and 2 juveniles from station X068; USNM 156685, 1 adult female with male and female choniostomatid copepods in marsupium, from station X052; USNM 157117, 1 ovigerous female and 3 juveniles from station X041.

DESCRIPTION OF ADULT FEMALE (Figures 27, 28).—Carapace shape and ornamentation (Figure 27) similar to that of adult female S. ocula.

Infold: Infold of caudal process with 5–7 bristles, 1 of these close to inner margin; 1 minute bristle on inner margin of infold just anterior to caudal process; 2 setose bristles on posterior infold dorsal to caudal process; 1 small bristle near middle of anterior infold.

Size (Figure 10): USNM 156654, length 1.43 mm, height with caudal process 1.48 mm, height without caudal process 1.21 mm; USNM 156685, length 1.37 mm, height with caudal process 1.47 mm, height without caudal process 1.19 mm; USNM 157117, length 1.52 mm, height with caudal process 1.42 mm, height without caudal process 1.19 mm; USNM 157116a, length 1.41 mm, height with caudal process 1.41 mm, height without caudal process 1.14 mm; USNM 157116b (carapace distorted) approximate length 1.34 mm, approximate height with caudal process 1.42 mm, approximate height without caudal process 1.32 mm (not included in Figure 10); USNM 157116c, length 1.35 mm, height with caudal process 1.42 mm, height without caudal process 1.15 mm; USNM 157116d, length 1.43 mm, height with caudal process 1.41 mm, height without caudal process 1.14 mm.

First Antenna: Similar to that of S. ocula (see Figure 24b).

Second Antenna: Protopodite bare. Endopodite 1-jointed with 2 short proximal, anterior bristles, and 1 spinous terminal bristle (Figure 28a) (bristle about same length as longer of 2 terminal bristles on endopodite of S. ocula, see Figure 24c). Exopodite similar to that of adult female S. ocula.

Mandible: Coxale endite consisting of short stout spine; lateral side of coxale with long hairs forming 2 rows near ventral margin. Basale: similar to that of adult female S. ocula (see Figure 24d). Endopodite: similar to that of adult female S. ocula except minute medial spine observed near base of ventral claw of 1st joint.

Maxilla: Bare bristle of exopodite slightly longer than that of adult female S. ocula, otherwise limb similar to that of S. ocula (see Figure 24e).

Fifth Limb: Epipodial bristles not counted. Limb similar to that of adult S. ocula except exopodial joints 2–5 with total of 7 bristles.

Sixth Limb: Single endite with 2 or 3 short bristles; end joint with 11–13 spinous ventral bristles in addition to 2 stout, hirsute bristles; medial surface near posterior margin with abundant long hairs. In general, similar to 6th limb of adult female S. ocula (see Figure 25a).

Seventh Limb: Limb similar to that of adult female S. ocula (see Figure 25b,c).

Furca: Similar to that of adult female S. ocula (see Figure 25d).

Rod-shaped Organ (Figure 28c): Elongate, broadening very slightly distally, with rounded tip.

Eyes: Lateral eye small with 4 ommatidia; pigment between ommatidia brown (Figure 28b,c). Medial eye bare, about twice size of lateral eye, with brown pigment (Figure 28c).

Upper Lip: Helmet shaped.

Genitalia: Consisting of oval sclerotized ring on each side of body anterior to furca.

Eggs: USNM 156654 with 6 eggs in marsupium; USNM 157116a, 10 eggs in marsupium; USNM 157117, 7 eggs in marsupium.

DESCRIPTION OF ADULT MALE (Figures 29–31).—Carapace with prominent rostrum and caudal process (Figure 29).

Ornamentation (Figures 29, 30a): Lateral rib near dorsal margin extending from tip of rostrum, where it projects anteriorly past anterior edge of valve, to posterodorsal part of valve, where it terminates in 2 spinous processes, each with single long bristle; a second lateral rib present just below valve middle, extending from rostrum to near posterior end of shell, and with 3 or 4 spinous processes; a third shorter rib with 3 spinous processes present near ventral margin; lateral side of caudal process with spinous process near middle; surface of valves with shallow fossae (Figure 30a); short spines abundant between fossae and on lateral ribs and processes; long bristles present along anterior and ventral margins and sparsely distributed on valve surface.

Size (Figure 10): USNM 156653, length 1.22 mm, height 0.82 mm.

First Antenna (Figure 30b): 1st joint: few spines on lateral surface. 2nd joint: few spines near dorsal margin and 1 dorsal subterminal bristle. 3rd and 4th joints: fused; 3rd joint with long dorsal and minute ventral bristle; 4th joint with 3 bristles (1 dorsal, 2 ventral). 5th joint: small, sensory bristle with cuplike proximal part with abundant filaments and stem with 3 or 4 marginal filaments. 6th joint: medial bristle short. 7th joint: a-bristle longer than combined length of joints 6–8; b-bristle bare, about one-third longer than a-bristle; c-bristle reaching past tip of sensory bristle of 5th joint, with 4 marginal filaments. 8th joint: d- and e-bristles bare, with blunt tips, slightly shorter than c-bristle; f-bristle slightly shorter than c-bristle, with 3 or 4 marginal filaments; g-bristle about same length as c-bristle, with 5 marginal filaments; minute spine at tip of sensory bristle, c-, f-, and g-bristles.

Second Antenna: Protopodite bare. Endopodite 1-jointed with 2 short proximal anterior bristles and 3 or 4 terminal bristles on low mound (1 of these longer than others) (Figure 30c,d). Exopodite: 1st joint with short terminal medial spine; bristle of 2nd joint with proximal natatory hairs on ventral and dorsal margins followed by 4–7 slender ventral spines and, then, natatory hairs on both margins; bristles of joints 3–8 with natatory hairs but without spines; 9th joint with 1 long and 1 short (dorsal) bristle with natatory hairs; joints without basal spines.

Mandible (Figure 30e): Coxale endite represented by ringed spine; ventral margin of coxale bare. Basale: ventral margin with 2 short midbristles; medial side with 4 bristles near ventral margin; dorsal margin with 2 bristles. Exopodite hirsute with base on lateral side of basale and distal part on medial side of 1st endopodite joint. Endopodite: 1st joint with abundant hairs on dorsal half of medial side and 1 long terminal ventral bristle with minute bristle near its base; 2nd joint with spines forming rows on medial surface, 1 ventral terminal bristle, and 1 dorsal midbristle; 3rd joint short, with stout terminal claw and 3 bristles near base of claw (2 ventral, 1 dorsal).

Maxilla (Figure 30f): Limb reduced, with weakly developed bristles.

Fifth Limb (Figure 30g): Single endite with 1 short bristle. Exopodite: 1st joint with 2 bristles; remaining joints fused, with total of 8 bristles; limb weakly developed.

Sixth Limb (Figure 31a): Single endite with 3 short bristles; end joint with 13 hirsute and spinous bristles.

Seventh Limb (Figure 31b): Consisting of minute stump.

Furca: Similar to that of adult female.

Rod-shaped Organ (Figure 31c): Similar to that of adult female.

Eyes: Lateral eye with about 9 ommatidia and with dark brown pigment between ommatidia (Figure 31d); medial eye pigmented, bare, about same size as lateral eye (Figure 31c).

Copulatory Organ (Figure 31e): Typical for genus.

Y-Sclerite (Figure 31f): Typical for family.

COMPARISONS.—The carapace of Sarsiella dornellasae is very similar in shape and ornamentation to that of S. ocula but is smaller (Figure 10). Each endopodite of the 2nd antennae of the adult and juvenile female of S. ocula in the collection has 2 terminal bristles, whereas, females of S. dornellasae examined (4 adults and 1 juvenile) have only 1 terminal bristle. The pigment between the ommatidia in the lateral eyes of all 3 specimens of S. ocula in the collection (1 adult female, 1 juvenile female, 1 adult male) is light amber, about the same color as the ommatidia. The pigment is brown in lateral eyes of S. dornellasae.