文档介绍：第三章昆虫的胚后发育Postembryonic development
孵化
生长与脱皮
变态
第一节孵化Hatching, Eclosion
幼虫从卵中破壳而出的过程。
To escape from the eggs, a larva must break the various membranes which surround it. These include the chorion, vitelline membrane.
破壳方式
化学物质
破卵器eggburster
上颚mandible
第二节生长与脱皮 Growth and moulting (ecdysis)
Insect growth is discontinuous, because the rigid cuticle limits expansion.
Size increase is by moulting (ecdysis).
The formation of new cuticle of greater surface area and shelding of the old cuticle. (由激素控制——蜕皮激素Ecdysone)。
蜕Exuvia
不同种脱皮次数不同,同种脱皮次数一般相同。一般脱皮2—20次
龄期stadium (stadia): The period between moults相邻两次脱皮之间的时间。
虫龄instar: The growth stage, or the form between two essive 。
first instar larva一龄幼虫、second instar larva二龄幼虫••••••
last instar larva末龄幼虫( full-grown larva老熟幼虫)
Insect development involve ponents of growth.
Moult increment蜕皮期生长
It is the increment in size occurring between one star and the next.
Intermoult period increment龄期生长
It is the increment in a stadium or instar duration.
第三节变态Metamorphosis
Metamorphosis: The relatively abrupt change in body form between the end of immature development and the onset of the imaginal (adult) phase.
胚后发育过程中,昆虫从幼期状态转变为成虫状态的现象。
5 patterns of development.
一、增节变态Anamorphosis
A metamorphosis in which the immature stages have fewer abdominal segments than the
是系统演化中多足纲遗留下来的特征。
二、表变态Epimorphosis
In Collembola, Diplura, Archeognatha and Thysanura, which as adults remain wingless, the degree of change from juvenile to adult is slight and is manifest primarily in increased body size and development of functional genitalia.
弹尾目、双尾目、石炳目、缨尾目
幼虫基本具备了成虫的特点
除了个体增大、触角及尾须节数增多、性器官继续成熟以外,性成熟后仍继续脱皮。
三、原变态Prometamorphosis
Nymphs of mayflies have 12-45 aquatic instars, and wings are visible in older nymphs. Between the nymph stage and adult stage there is a subimago . 蜉蝣幼虫到成虫期之间有一个很短的“亚成虫期”。
The subimago is fully winged, flying or crawling.
四、plete Metamorphosis
一生只经历三个虫期:egg-juvenile-adult sta