In the second stage, answering to the chrysalis stage of butterflies, they have six pairs of beautifully constructed natatory
legs, a pair of magnificent compound eyes, and extremely complex antennae; but they have a closed and imperfect mouth, and cannot feed: their function at this stage is, to search by their well-developed organs of sense, and to reach by their active powers of swimming, a proper place on which to become attached and to undergo their final metamorphosis.
setae emerge from the proximal region of the upper notopodial and lower neuropodial lobes beginning on setiger twenty seven.
Third instars of these taxa are separated by the presence of natatory
(swimming) sensilla on tibiae and tarsi of Neoporus and their absence on Heterosternuta (Alarie 1991).
The long antennular aesthetascs and the long plumose natatory
setae of the first and second maxillipeds have been drawn truncated.
Morphological adaptations for pelagic life such as natatory
exopods, which occur in all species, and lightly calcified, almost membranous exoskeleton of some genera are evidence of the habitat they occupy (Bauer, 2004).
Setae of antenna II not very long but reach the tip of terminal portion.
Moreover, they have adaptations to the aquatic locomotion, such as an oval and dorsoventrally flattened body shape, and the last pair of legs broadened, flattened and provided with natatory
setae that aid in underwater propulsion (Larson et al.
Sympods of all legs and natatory
lobes bearing plumose setae similar to those on exo- and endopods.
Hindfeet without natatory
fringes-- continuous combs of stiff hairs along the plantar margins and sometimes between the digits (Fig.
Also, its wide distribution may be related to its highly nektonic character because this species has longer natatory
setae (Wurdig et al.
These larvae appeared to have been hatched prematurely, and their morphology differed from that expected for a first-stage zoea form in that maxillipeds were devoid of natatory
setae (see Morphology section above).
setae, with diameters of about 2 [micro]m, experience Reynolds numbers of about 0.