Is it a mite?

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Nomenclature

Opilionida (Opiliones, Phalangida, including Cyphophthalmi)

Common names

harvestmen, opilionids, daddy-long-legs

Probability of encounter

high

Quarantine importance

No known importance.

Similarity to mites

Some groups very mite-like, especially in dorsaldorsal:
relating to the upper or back side; opposed to ventral.
view where the bodybody:
the idiosoma of mites.
may appear unsegmented. However, at least the venterventer:
the lower or under side; opposed to dorsum.
of the opisthosomaopisthosoma:
(= abdomen) the posterior body division in arachnids; usually not distinct in mites because of the fusion of the opisthosoma with part of the prosoma to form the idiosoma.
should be clearly segmented, even in immatures.

Morphology

Normal adult length: <15 mm
Bodybody:
the idiosoma of mites.
tagmata: prosomaprosoma:
(= cephalothorax) the anterior body region in arachnids; usually not distinct in mites.
, opisthosomaopisthosoma:
(= abdomen) the posterior body division in arachnids; usually not distinct in mites because of the fusion of the opisthosoma with part of the prosoma to form the idiosoma.
(but superficially appears as one bodybody:
the idiosoma of mites.
mass)
Eyes: 1 + 1 ocelliocellus:
(pl. ocelli) a simple eye.  Mites with eyes usually have one or two pairs of lateral ocelli, but some Opilioacarida have three pairs.  Additionally, some acariform mites have one or two median ocelli on the underside of the naso.
on median turret (or blind)
Antennae: absent
Mouthparts: 3-segmented chelicerae; leg-like or raptorialraptorial:
(Latin raptor = robber) modified for capturing prey; predatory.  The pedipalps (e.g., many Cunaxidae) or legs I may be raptorial in mites.
palps
Legs: 4 pairs; legs I or legs II antenniform
Distinguishing features: eye turret; repugnatorial glands; particulate feeding

Diversity

ca. 5,000 species

References

• Edgar 1990Edgar 1990:
  Edgar AL. 1990. Opiliones (Phalangida). pp. 529-581. In: Dindal DL. (Ed.) Soil biology guide. John Wiley & Sons, Brisbane.