First pair of pereopods overreaching scaphocerite with distal portion of carpus.
The two species can be distinguished in adult males by differences in the second pair of pereopods: (a) the largest second pereopod overreaches the scaphocerite with ca.
Diagnosis: rostrum in adults not reaching scaphocerite end, shorter than carapace (brooked at south Atlantic examined specimen); branchiostegal spine strong, flared outwards, with distinct carina extending backwards on to carapace for three times the spine length (Figs.
Diagnosis: rostrum usually as long as carapace, overreaching scaphocerite, ventral margin straight, with six teeth, dorsal margin with eight teeth; antennal spine present; branchiostegal spine present with distinct carina extending twice the length of the spine.
Diagnosis: rostrum directed anterodorsally, large at base tapering to tip, short, reaching a maximum of 3/4 scaphocerite length, dorsal margin slightly concave, with 7-8 teeth at all rostrum length, ventral margin sinuous with or without 0-3 sub-distal teeth; antennal spine present, branchiostegal spine absent, pterygostomian spine present without carina; hepatic groove present; cervical groove well developed; branchiostegal suture not well developed; eyes with cornea weakly developed, more slender than the ocular peduncle; scaphocerite with short distal spine not overreaching blade; stylocerite short, not overreaching the antennular peduncle first segment distal margin (Fig.
Second pair of pereopods different in size and pubescent; the larger second pereopod overreaching scaphocerite with entire carpus; merus 0.7 to 1.0 x carpus length, 0.7 to 1.0 x palm length, and 0.4 x chela length; carpus 0.4 to 0.6 x chela length, with a spine at inner distal border; fingers 1.0 to 1.2 x palm length, 1 to 2 teeth on proximal portion in cutting edge of each fingers (Fig.
Rostrum straight, as long as or slightly longer than scaphocerite; upper margin with 6 to 9 teeth, including 1 to 3 completely post orbital, lower margin 1 to 4 teeth (Fig.
Rostrum straight, as long as scaphocerite; upper margin with 7 to 9 teeth, including 1 to 2 completely post orbital, lower margin 2 to 3 teeth (Fig.
amazonicum can be recognized by the long slender rostrum, which reaches distinctly beyond the scaphocerite, the anterior tip directed upwards.
jelskii are: the slender rostrum with the tip curved upwards, reaching beyond the scaphocerite. The dorsal margin bears 6 to 7 (rarely 5 to 8) teeth, excluding the subapical.
The morphological characters of the first postlarva are 43 scaphognathite setae on the maxilla, three scaphocerite spines on the outer margin of antenna, and sternal plate spines: 2,2,0,1,1.
7B): Biramous; protopod two-segmented; endopod and exopod unsegmented; endopod with three naked setae; exopod (scaphocerite) with 12 marginal plumose setae.