Table 3 Similarities and differences between postlarval instar 2 of the pallenopsids studied
Instar 2 | Species | ||
|---|---|---|---|
P. villosa | P. hodgsoni | P. vanhoeffeni | |
Nutrition | ? | lecithotrophic | lecithotrophic |
Body length (mm) | ? | 1.2–1.4 | ≥1.5 |
Ocular tubercle | ? | dome-shaped | cone-shaped w/ pointed tip |
Eyes/eye anlagen | ? | present | present |
Proboscis | ? | gradually tapering, increasing toward tip | +/− cylindrical w/ tapering only in distal portion |
Cheliphore | ? | 3-articled | 3-articled |
Chela fingers | ? | proximal portion +/− straight, then curving toward tip | proximal portion +/− straight, then curving toward tip |
Attachment gland process | ? | single & short | single & short |
Scape setae | ? | 1 distal & dorso-lateral | 3–4 distal & evenly spaced along the dorsal side |
Chela setae | ? | 1 dorsal & ventral to mf base; 1 dorsal & 1–2 ventral to ff base | 2–4 along mf base; 1 dorsal & 1–2 ventral to ff base |
Palpal larval limb | ? | externally 3-articled; > > ovigeral limb; atrophy of limb tissue | externally 3-articled =ovigeral limb; atrophy of limb tissue |
Ovigeral larval limb | ? | externally 2-articled; atrophy of limb tissue | externally 3-articled; atrophy of limb tissue |
Walking leg 1 | ? | 9-articled | 9-articled |
Walking leg 2 | ? | 9-articled | 9-articled |
Walking leg 3 | ? | elongate limb bud; internally 9 articles defined | elongate limb bud; at least 8 articles internally defined |
Walking leg 4 | ? | tiny elevation w/ compressed internal tissue | tiny elevation w/ compressed internal tissue |
Walking leg 1&2 setae | ? | fe, tb1 & 2 w/ dorso-distal setae; only tb2 w/ 1 dorsal seta at mid-length | fe, tb1 & 2 w/dorso-distal setae; tb1 & 2 w/ at least 3 dorsal setae at mid-length |
Anal tubercle | ? | w/ slit-shaped proctodeum; anus not open yet | w/ slit-shaped proctodeum; anus in some specimens open |
Ventral side of trunk | ? | segmentation lines between wl segments | segmentation lines between wl segments |
Dorsal side of trunk | ? | no signs of segmentation | no signs of segmentation |
Gabelborsten | ? | ca. 10 μm; multifurcating but arranged in two main bundles | 20–30 μm; bi-, tri- or tetrafurcating |
Central nervous system | ? | all ganglion anlagen well-defined | all ganglion anlagen well-defined |