dcsimg

Comprehensive Description

provided by Smithsonian Contributions to Zoology
Parawaldeckia yamba

DESCRIPTION (of female from South Australia).—Eye elongate-oval, deep brown in alcohol; lateral cephalic lobes evenly triangular; prebuccal mass deeply produced, rounded; upper lip formed of small, narrow asymmetrical lobe hanging from epistome, posterior margin with setulose hump; article 3 of mandibular palp about 55 percent as long as article 2, bearing 3 apical setae, article 2 with 3 short setal spines apically; article 1 about 50 percent as long as article 2; apex of palp on maxilla 1 sharp, inner plate with 1 short seta; coxa 1 strongly expanded and slightly extended anteroventrally; posterior margin of hand on gnathopod 1 with 5 medium-sized serrations, dactyl bearing distal accessory tooth, otherwise simple; palm of gnathopod 2 protuberant, dactyl attached in middle of hand apex, hand wider than distal third of article 5 but 1.7 times as long as broad; pereopods 1–5 with very small spines on active margins of article 6, dactyls with weak slit and vestigial accessory setule-tooth; article 4 of pereopods 1–2 twice as broad as articles 5–6; article 4 of pereopods 3–5 broadly expanded on pereopod 5, its process reaching less than halfway along 5 (see Figures 162P3–5 for details of shapes of articles), article 2 of pereopod 5 posteroventrally beveled; pleonal epimeron 1 with anteroventral protrusion softly rounded, epimera 2–3 softly quadrate posteroventrally; pleonite 4 with low dorsal mound behind dorsal saddle; inner ramus of uropod 2 with 1 spine in normal-sized notch; peduncle of uropod 3 moderately expanded, half as broad as long, inner ramus about 35 percent as long as outer (including basal immersed portions), outer ramus with article 2 clearly articulate; depth of medial incision on telson about 20 percent of length, each apex armed with 1–2 large and 1–2 small spines, each lateral margin with notch near middle bearing 2 fat plumose seniles, each apex with subterminal plumose setule or spinule.

Adult males differing from females in the elongate antenna 2, the shorter cephalic lobe with small mammilliform projection, the more broadly rounded epistome projecting less, the hand of gnathopod 1 bearing only 4 posterior serrations, the flatter dorsal margin of pleonite 4, the different epimeral shapes (Figure 163En), the reduction of spines on uropod 2 to 1 spine on the outer ramus and no spines on the inner, the grossly setose uropod 3, and the longer, narrower telson. This male, 5.2 mm, and others are far better developed than the 7.0 mm male of adolescent description below.

ADOLESCENT MALE (from Western Australia).—Antenna 2 elongate, about half as long as body, eyes scarcely larger than those of female; inner ramus of uropod 3 conical, 70 percent as long as outer; dorsal hump of pleonite 4 slightly flatter than in female.

FEMALE AND MALE (from Southwestern Australia). —Uropod 2 with only 1 spine on outer ramus and none on inner ramus.

HOLOTYPE.—SAM, sex unknown, 6.2 mm.

TYPE-LOCALITY.—Shepherd 40, D-282, Point Gilliam, West Island, South Australia, 0–4 feet, among corallines, Asparagopsis armata, and Halopteris species, 27 May 1967.

RELATIONSHIP.—The incised telson distinguishes this species from the type, P. thomsoni (Stebbing, 1906); the latter also has an upturned acute posteroventral corner of epimeron 3.

This species differs from Stephensen’s (1927) identification of P. hidderi from the Auckland and Campbell islands by the presence of spines on the telson. Stephensen’s synonymy of P. kidderi is erroneous, as Stebbing’s (1888) Socarnoides kergueleni is not in Parawaldeckia and Monod’s (1926) identification appears to be correctly Nannonyx kidderi, but the latter species belongs with a distinct, perhaps undescribed, genus (see J. L. Barnard, 1969a).

The material figured herein is of the female-like morphology, the antennae being short, but the specimen lacks brood plates.

MATERIAL.—Shepherd 40 (2), 46 (1); JLB Australia 4 (1), 10 (2), 12 (17), 13 (20).

DISTRIBUTION.—Warm-temperate Australia, littoral and sublittoral.

Tryphosella Bonnier
license
cc-by-nc-sa-3.0
bibliographic citation
Barnard, J. L. and Drummond, M. M. 1978. "Gammaridean Amphipoda of Australia, Part III. The Phoxocephalidae." Smithsonian Contributions to Zoology. 1-551. https://doi.org/10.5479/si.00810282.103

Depth range

provided by World Register of Marine Species
Littoral (0 to 30 m) 0-1.5 m.
license
cc-by-4.0
copyright
WoRMS Editorial Board
contributor
Lowry, Jim [email]
contributor
Lowry, Jim [email]

Habitat

provided by World Register of Marine Species
Marine, among coralline algae (e.g. Asparagopsis armata & Halopteris spp.)
license
cc-by-4.0
copyright
WoRMS Editorial Board
contributor
Lowry, Jim [email]
contributor
Lowry, Jim [email]