A report on Arachnid and Hemolymph

A grasshopper has an open circulatory system, where hemolymph moves through interconnected sinuses or hemocoels, spaces surrounding the organs.
Basic characteristics of arachnids include four pairs of legs (1) and a body divided into two tagmata: the cephalothorax (2) and the abdomen (3)
Above is a diagram of an open circulatory system. An open circulatory system is made up of a heart, vessels, and hemolymph. This diagram shows how the hemolymph is circulated throughout the body of a grasshopper. The hemolymph is first pumped through the heart, into the aorta, dispersed into the head and throughout the hemocoel, then back through the ostia that are located in the heart, where the process is repeated.
"Arachnida" from Ernst Haeckel's Kunstformen der Natur, 1904
Hubbardia pentapeltis (Schizomida)
Fossil Goniotarbus angulatus (Phalangiotarbi)
Fossil of Kreischeria (Trigonotarbida)
Eukoenenia spelaea (Palpigradi)

It is the major tissue type of the open circulatory system characteristic of arthropods (e.g. arachnids, crustaceans and insects).

- Hemolymph

Spiders and whipscorpions extend their limbs hydraulically using the pressure of their hemolymph.

- Arachnid

1 related topic with Alpha

Overall

Arthropod

0 links

Arthropods (, (gen.

Arthropods (, (gen.

Structure of a biramous appendage.
Alignment of anterior body segments and appendages across various arthropod taxa, based on the observations until mid 2010s. Head regions in black.
Illustration of an idealized arthropod exoskeleton.
Cicada climbing out of its exoskeleton while attached to tree
Arthropod eyes
Head of a wasp with three ocelli (center), and compound eyes at the left and right
Compsobuthus werneri female with young (white)
The nauplius larva of a penaeid shrimp
Marrella, one of the puzzling arthropods from the Burgess Shale
Kylinxia
The velvet worm (Onychophora) is closely related to arthropods
Insects and scorpions on sale in a food stall in Bangkok, Thailand

The haemocoel, an arthropod's internal cavity, through which its haemolymph – analogue of blood – circulates, accommodates its interior organs; it has an open circulatory system.

The four major groups of arthropods – Chelicerata (sea spiders, horseshoe crabs and arachnids), Myriapoda (symphylan, pauropods, millipedes and centipedes), Crustacea (oligostracans, copepods, malacostracans, branchiopods, hexapods, etc.), and the extinct Trilobita – have heads formed of various combinations of segments, with appendages that are missing or specialized in different ways.