Here are two questions, hoping to read the mental answers.
Understand that people will see at a glance that the center of the picture is a hard insect cocoon, to put it bluntly, this is a wintering insect cocoon made of yellow thorn moth, and the hardness of this cocoon is usually difficult for people to crush with their index fingers and thumbs. But there is a small circular hole in the carcass of this hard cocoon, and furthermore, this small round hole is actually a trace left by a parasitic wasp when it pierces the cocoon shell with a stinging needle (egg layer) to lay eggs...
So let's talk about the thorn moth first, for it is not unfamiliar to everyone, the larvae of the thorn moth mostly hatch during the day. The hatching larvae first eat the egg shell, then feed on the epidermis and leaf flesh of the leaf, and at 4 years old, they eat the leaves to form holes; the 5th and 6th instar larvae can eat the whole leaf and leave only the leaf veins. The larvae are heterogeneous, and when they are old, they spit silk on the branches of the tree as a cocoon. The cocoon is transparent at the beginning, and the activity of the larvae in the cocoon is visible, and then condenses into a hard cocoon. The cocoon is initially off-white, but soon turns brown and reveals white longitudinal stripes.
Here is a question, this cocoon is very hard, is calcareous, the initial cocoon shell transparent shell is softer, and then the calcium of the hardening process is where it comes from?
Let's talk about the Purple Wasp, an important parasitic predator of the stinging moth, which occurs once a year, with larvae overwintering in the cocoon of the stinging moth. In late June of the following year, the overwintering larvae pupate, and in mid-July begin to feather the adults, and the adults lay eggs to parasitize the larvae in the cocoon of the stinging moth, and then overwinter in the host cocoon in a larval state. The egg and pupae stages are 6 - 8 days, the adult lifespan is generally 15 - 20 days, the adult moth Purple Peak is mostly feathered during the day, before feathering, often make a crackling bite cocoon sound, and then bite through the cocoon shell to go out. Males generally feather 7- 10 days earlier than females, females can mate on the same day, and males follow the females during mating, constantly swinging their antennae, and mating once the females stop mating. The female only mates once in her life, and the next day after mating, she looks for a host to lay eggs. Before laying eggs, the position of the cocoon of the stinging moth is probed with antennae, and then the oviposiform is inserted into the appropriate part of the cocoon to parasitize the larvae of the stinging moth. Only 1 egg is laid in 1 cocoon, and it takes about 30 to 45 minutes to lay each egg.
A question is also raised here, which talks about the hardness of the cocoon shell of the thorn moth, so the egg laying apparatus of a weak parasitic wasp is not a "diamond" after all, right? What force does it use to pierce the hard cocoon shell to carry out the parasite body?