Comprehensive Description

provided by Smithsonian Contributions to Zoology
Syndexamine mullauna

DESCRIPTION OF FEMALE.—Antenna 1 extending much farther than antenna 2, both pairs of antennae short, antenna 1 thick, article 1 bearing one medium ventral spine and a setule, article 2 scarcely shorter than 1, flagella of antennae very short; spines on articles 4–5 of antenna 2 medium to small; lateral cephalic lobes broad and slightly incised, anteroventral cephalic margin with strong bulge supporting base of antenna 2; upper lip rounded below; mandibles very thick, incisors untoothed, right mandible with two spines, left with three, each molar with ragged seta, short ordinary setae on right, essentially no setae on left except main ragged member, molars scarcely triturative; each outer lobe of lower lip with medium cone (half as long as in S. wane J. L. Barnard, 1972a), mandibular lobes broad, blunt, short; inner plate of maxilla 1 with two setae in tandem on subapical medial margin, outer plate with 11 spines, apex of palp with two weak cones and four setae; inner plate of maxilla 2 with numerous facial setules, first proximal main seta not divorced from next distally, lobes like those in S. wane except inner plate slightly enlarged; maxilliped like that of S. wane; coxa 2 with one posterior seta, coxa 3 with one thin posterior spine, coxa 1 with concave anterior margin and slightly upturned anteroventral corner; gnathopod 1 like that of S. wane, palm nearly transverse but convex, gnathopod 2 like gnathopod 1, with similar obliquity to palm; pereopods 1–2 stout, spines small, posterior margin of article 6 weakly notched, article 6 thus not appearing prehensile; pereopods 3–5 with article 2 thin and rectangular, remaining articles of pereopods as short and stout as in S. wane, pereopods 3–4 with heavily prehensile appearance as active margin of article 6 bearing button-hook protuberance near base armed with three stout spines, remainder of margin nearly smooth and slightly excavate, article 6 of pereopod 5 like that of pereopods 1–2, dactyls very long, article 2 of pereopods 4–5 with weak posterodorsal ala, dactyls with main marginal seta free but recumbent; inner rami of uropods 1–2 distinctly shorter than outer, outer ramus of uropod 2 lacking dorsal spine; uropod 3 with rami bearing many heavy spines, apices rounded, one or more spines apically, outer ramus as long as inner; telson of medium width, each apex bearing one spine; pleonal epimera 1–3 with lateral ridge and weak tooth on 1–2, strong on epimeron 3, epimeron 2 with one spine above ventral spines; pleonite 3 protuberant dorsally, pleonite 4 with large, vertically erect protuberance; cuticle bearing moderately strong polygons.

Other details in comparison to S. wane: Body appearance similar, inner plate of maxilliped with three medial setae instead of two; two seta-aesthetascs of accessory flagellum longer than in S. wane; antenna 1 with stout aesthetacs and apically tubular setae as in S. wane; coxa 1 with three mediofacial setae; palms of gnathopods weakly and very finely wavy, dactyls bearing weak subdistal facial setules (unlike S. wane but normal to dexaminids), nine setae in oblique mediofacial row on hands of gnathopods, dorsal setae in three sets, large gap between sets 1 and 2, on gnathopod 1 these sets, distal to proximal, bearing five, five, and four setae, on gnathopod 2 bearing three, four, and four setae; ventral spines on epimera 1–3=one, three, six; dorsolateral ridges of urosomites 2–3 (fused) lacking spines. Male unknown.

HOLOTYPE.—SAM, female, 4.1 mm. Unique.

TYPE-LOCALITY.—Shepherd 9, Pearson Islands, South Australia, Station B, 15 feet, algae on horizontal face, 8 January 1969.

DISTRIBUTION.—Pearson Islands, South Australia, 5 m.
bibliographic citation
Barnard, J. L. 1974. "Gammaridean Amphipoda of Australia, Part II." Smithsonian Contributions to Zoology. 1-148. https://doi.org/10.5479/si.00810282.103