(Figs 3, 4)

Type material. Holotype, male 1.8 mm, AM P70701, Watsons Bay, Lizard Island (14°39.689'S 145°26.872'E), scrapings from mooring block, sandy bottom with mounds and Udotea, 8.3 m, P.B. Berents & L. Hughes, 24 February 2005 (QLD 1636). Paratypes: 3 males, 4 females, AM P75465 (QLD 1636), 3 males, 9 females, AM P70716 (QLD 1636), same data.

Type locality. Watsons Bay, Lizard Island, Queensland, Australia (14°39.689'S 145°26.872'E).

Etymology. Referring to its diminutive size.

Description. Based on holotype, male, 1.8 mm, AM P70701.

Head. Head lateral cephalic lobes apically round, Antenna 1 flagellum with about 9 articles; accessory flagellum absent. Antenna 2 with few long setae. Lower lip with fine setae only. Maxilla 1 inner plate with 1 long pectinate apical seta. Mandible, palp article 3 longer than 2, posterior margin straight, posterior margin without setae

Pereon. Pereonites without sternal spines. Gnathopod 1 enlarged in males only; coxa weakly produced anterodistally; basis slender, less than half as broad as long, without a spine, posterodistal margin with setae absent, anterodistal margin with weak flange; ischium anterior margin without flange, posterodistal margin without setae; merus greatly elongated, distally free and produced along posterior margin of carpus, posterior margin with few setae, without posterodistal spine; carpus longer than propodus, anterior margin without setae, without spine, posterior margin without spines; propodus anterior margin with few setae, posterior margin straight, palm absent; dactylus less than half length of propodus. Gnathopod 2 subchelate; basis anterodistal margin straight, without flange, posterodistal margin without robust setae; merus not enlarged; carpus longer than propodus, anterior margin not lobate, with short, sparse setae; propodus anterior margin with short sparse setae, with robust seta defining palm. Pereopod 3 without brush of long setae on merus. Pereopod 6 basis not or weakly produced posterodistally. Pereopod 7 significantly less than 125% length of pereopod 6.

Pleon. Epimeron 3 posterodistal margin with small notch. Uropod 1 rami subequal, peduncle much longer than broad, distoventral spine shorter than peduncle. Uropod 2 biramous, inner ramus longer than outer ramus, peduncle with short distoventral spine less than one quarter length of peduncle. Uropod 3 biramous, rami subequal, inner ramus shorter than peduncle. Telson with distal fine setae only.

Female (sexually dimorphic characters). Based on paratype, female, 2.1 mm, AM P75465. Gnathopod 1 merus not greatly elongated, not distally free; carpus shorter than that of male, subequal with propodus. Gnathopod 2 more slender than that of male, carpus shorter than propodus.

Habitat. Among encrusting flora and fauna on mooring block, over sandy bottom.

Remarks. A. parvus differs from most described species of Aoroides by the poorly setiferous male gnathopod 1 and by the very short dactylus of that appendage. It differs from A. nahili J.L. Barnard, 1970 in having the merus of the male gnathopod 1 shorter than the carpus, inward curved and not ending acutely and from A. columnaris Ariyama, 2004 and A. curvipes Ariyama, 2004 in the weakly produced male coxa 1.

Distribution. Australia. Queensland: Lizard Island (current study).