Larva medium sized, up to 5 mm long, red. Head capsule evenly golden to golden-brown (amber) coloured; mentum and mandibular teeth darker. Occipital margin not darkened
SIII seta on clypeus, separate from frontal apotome; labral sclerites fragmented, sclerite 2 distinct.
Antenna with 5 segments, segment 2 subequal or shorter than 3rd, remainder diminishing in size; AR < 1. Ring organ in basal 1/4 - 1/3 of segment 1, seta absent. Blade extending to near apex of 3rd segment, accessory blade 1/2 length of blade. Lauterborn organs opposite on apex of 2nd segment, as long as segment 3. Style about half length of segment 3.
SI broadly plumose, and SII longer, narrowly and weakly plumose; SIII simple, short; SIVa and b short. Seta premandibularis simple. Labral lamellae broad, without indication of median division, with 15-30 teeth. Pecten epipharyngis of three digitiform scales, basally with indication of microteeth. 7-9 apically plumose chaetulae laterales, 2 apically branched chaetulae basales. Premandible with 2 teeth and strong brush.
Dorsal tooth absent, with pale apical tooth and 4 dark, pointed inner teeth. Pecten mandibularis absent. Outer margin smooth, inner margin (mola) with some spines. Seta subdentalis inserted on dorsal surface, long, curved extending to apical mandibular tooth. Seta interna inserted on dorsal surface, with 2 major branches, each strongly plumose, multi-branched.
Mentum with simple, broad, rounded median tooth, more protruding 1st laterals with slight to well developed lateral notches, laterals evenly sloping from 1st to outermost. Ventromental plates slender and scarcely separated medially, wider than mentum width, with dense, more or less parallel striae. Setae submenti simple.
Without prominent body setae; with or without short, posterodorsally-directed lateral tubules arising from posterior pleurae. Procerci stout, digitiform, posteriorly curved, length 2-6 times width, arising close together from broad basal tubercle that overhangs segment XIII. Anal tubules elongate, about 1/5th length of body and extensively tracheated, or shorter than posterior parapods, digitiform, not extensively tracheated. Anterior parapods with smooth long claws, short claws with few minute inner teeth, or also smooth; posterior parapod claws simple
Manoa belongs to the tribe Pseudochironomini, distinguished from other Chironominae by the SI setae arising from a common base, antennae not mounted on elongate pedestal, mandible without dorsal tooth and with the seta subdentalis inserted on the dorsal side. The second lateral tooth of the mentum is reduced and largely appressed (fused) to the first lateral tooth.The long ventromental plates touch or almost touch medially. The procerci of Manoa arise from a common base that overhangs the last body segment, whereas the procerci of the otherwise quite similar (and related) Pseudochironomus are shorter and arise separately.
Manoa was described from all stages from Amazonia, and a second adult species has been described from East Africa. In the Florida Everglades, M. pahayokeensis are found in shallow water areas subject to fluctuating water levels and seasonal drying.