abdominal appendage造句

• These species have small abdominal appendages, but robust legs well adapted for walking.
• Female crabs generally carry their eggs attached to the abdominal appendages until they hatch.
• However, apterygotes ( bristletails and silverfish ) and many immature aquatic insects have abdominal appendages.
• In this stage, the pleopods ( swimmerets; abdominal appendages ) become functional, and the animal closely resembles the adult form.
• These vesicles are derived from the coxal and trochanteral endites ( inner annulated lobes ) of the ancestral abdominal appendages.
• The abdominal appendages of modern chelicerates are missing or heavily modified while those of horseshoe crabs ( Xiphosura ) form gills.
• However, since crabs use the first two pairs of pleopods ( abdominal appendages ) for sperm transfer, this arrangement has changed.
• The eggs can sometimes be seen attached to the hairs on the second abdominal appendage of the female crab alongside her own eggs.
• One reason for this could be that the modification of the abdominal appendages into male copulation organs emerged later than the evolution of flight.
• The caterpillar has two abdominal appendages which serve as triggers to initiate a backward motion by which it grasps prey insects using spiny pair of forelegs.
• Modern Archaeognatha and Thysanura still have rudimentary appendages on their abdomen called styli, while more primitive and extinct insects known as Monura had much more developed abdominal appendages.
• It looks like abdominal appendages modified for sperm transfer and direct insemination have occurred at least twice in insect evolution, once in Odonata and once in the other flying insects.
• Another scenario is that abdominal appendages adapted for direct insemination have evolved three times in insects; once Odonata, once in mayflies and once in the Neoptera, both mayflies and Neoptera choosing the same solution.