ITP Logo

Major mite taxa—Key feature pages

 

Division of dorsal shield

In acariform mites, a putative remnant of the chelicerate prosomaprosoma:
(= cephalothorax) the anterior body region in arachnids; usually not distinct in mites.
 is often defined by a dorso-sejugal suturesejugal suture:
(or plane) a division cutting the acariform mite idiosoma between legs II-III.
 (below left) that separates the posteriorposterior:
the back part of the body or towards that region in comparison, e.g., 'posterior to'.
 notogaster from an anterior prodorsumprodorsum:
the dorsal surface of the propodosoma.
. This division is visible in most sclerotized acariform mites, especially in the traditional oribatid mites, Astigmata hypopi, and also in some Prostigmata and Astigmata adults.

In contrast, the dorsosejugal planesejugal suture:
(or plane) a division cutting the acariform mite idiosoma between legs II-III.
 is not visible in parasitiform mites, and the idiosoma is completely covered by a single holodorsal shieldholodorsal shield:
a shield that covers all of the dorsum.  In Mesostigmata, the holodorsal shield is often interpreted as resulting from the fusion of podonotal and opisthonotal shields and a suture between these regions is often visible (see recurved and procurved).
 (below middle) in Holothyrida and many Mesostigmata. This is also true in some armored Prostigmata (e.g., Labidostommatina) and the dorso-sejugal suturesejugal suture:
(or plane) a division cutting the acariform mite idiosoma between legs II-III.
 may be obscured in many derived Brachypylina. The holodorsal shieldholodorsal shield:
a shield that covers all of the dorsum.  In Mesostigmata, the holodorsal shield is often interpreted as resulting from the fusion of podonotal and opisthonotal shields and a suture between these regions is often visible (see recurved and procurved).
 is often divided in the Mesostigmata, but the division is posteriorposterior:
the back part of the body or towards that region in comparison, e.g., 'posterior to'.
 to the legs (below right), and no dorso-sejugal suturesejugal suture:
(or plane) a division cutting the acariform mite idiosoma between legs II-III.
 is present.

Multiple dorsaldorsal:
relating to the upper or back side; opposed to ventral.
 shields are present in many mites, as are reductions of shielding to a single anterior plate or completely soft cuticle.

Feature pages