Arthropods are divided into which subphylums and which orders?

Arthropods are divided into five subphylums and fifteen orders.

Subphylum Trilobata: Trilobata

Subphylum Chelicerata: Cephalopoda, Arachnida, Arachnida

Subphylum Crustacea: Cephalopoda, Paddle-footed, Gill-footed, Mollusca, Jaw-footed

Subphylum Hexapoda: Endostomatopoda, Insecta

Subphylum Polypoda: Peplopoda, Labialopoda, Oligopoda, Syndesmodonta

Arthropoda Body symmetrical on both sides. It consists of a series of body segments, which are heterorhythmically segmented and can be divided into head, thorax, and abdomen, or the head and thorax are fused into a cephalothorax, or the thorax and abdomen are fused into a carapace.

For example: Insecta (locusts) are divided into head, thorax and abdomen; Crustacea (shrimps) are divided into head, thorax and abdomen; Arachnida (spiders) are divided into head, thorax and abdomen; and Polypoda (centipedes) are divided into head and trunk.

The divisions of the body also appear as divisions in physiological functions:

Head: sensory and feeding center; thorax: locomotor and support center; abdomen: nutritional and reproductive center.

Expanded Information

Most arthropods are dioecious and often monoecious. Terrestrial species often undergo internal fertilization, while many aquatic species are fertilized in vitro. Generally oviparous, but also ovoviviparous. Oviposition is by epigynous cleavage, and there is both direct and indirect development. Indirectly developing species have one to several different larval stages, and sometimes the habits of these larvae differ from those of the adults.

There are also some arthropods that are capable of parthenogenesis, in which an unfertilized egg develops into an adult. There are also forms of larval reproduction and polyembryonic reproduction. There is no asexual reproduction in arthropods.

Most arthropods are dioecious, except for a few crustaceans such as tracheopods and parasitic isopods. Individual appendages change into mating organs. Terrestrial species often carry out internal fertilization, while many aquatic species for in vitro fertilization. Reproduction is diverse, generally oviparous, but also ovoviviparous; in addition to hermaphroditism, there are also forms of monoecious reproduction, larval reproduction and polyembryonic reproduction, and so on.

Many arthropods have a large reproductive output, less yolk, and the fertilized eggs hatch quickly into larvae. Some eggs contain a lot of yolk, are well protected by the egg shell or by the mother, and hatch to a size similar to that of the adult.

Generation interval in some insects and small crustaceans less than 3 days, so a pair of hermaphroditic females or a single female in a few weeks can produce millions of offspring, on the contrary, some of the large cold-water shrimp and crab 4 years old or more before maturity, spawning once every other year.

References:

Baidu Encyclopedia - Arthropods