12 other traits

Exceptional, plesiomorphic [P] and apomorphic [A] characters in the Oribatida (Grandjean, 1969, pp. 147, 148) and states for cladistic analysis. Polarity of characters: 0, primitive state; 1, derived state.

Abbreviations: PAL, Palaeosomata; ENA, Enarthronota; PAR, Parhyposomata; MIX, Mixonomata; DES, Desmonomata; CIR, Circumdehiscentiae; + means that there are some exceptions.

Notogaster

1/ Peranal segment [P]: (0) present in tritonymphs and adults v. (1) absent in all instars.

2/ Erectile setae [A]: (0) absent v. (1) present.

3/ Pseudanal setae [A]: (0) normal v. (1) swollen or hypertrophied (i.e.‘heterotrichous’ pseudanal rows ps present).

Podosoma

4/ Posterior humps regarded as a residue of legs IV in larvae [P]: (0) present v. (1) absent.

5/ Anterior and posterior plicature bands allowing the animal to curl up (i.e. ‘ptychoidy’) [A]: (0) absent v. (1) present in adults at least.

Ventral region of opisthosoma

6/ Varied setae (genital, eugenital, and of rows h and ps) [A]: (0) normal v. (1) hollow and turgid.

Legs

7/ Dorsal setae in patellae and tibiae [P]: (0) free v. (1) coupled with a solenidion (i.e. hollow, monorefringent, seta-like, most often olfactory receptor; cf. Alberti, 1998), reduced in size or suppressed.

8/ Solenidia of the tarsus in legs III [P]: (0) one emerging in deutonymphs v. (1) zero, one (but emerging in larvae) or two.

9/ Famuli (usually small, hollow, birefringent and spine-like organs inserted dorsally on tarsi I) [P]: (0) with bracteae (i.e. smooth, relatively thick and large, curved spines) v. (1) without bracteae.

10/ Apoteles (or ambulacra or claws), ungues in larvae and nymphs [P]: (0) three (i.e. ‘tridactyly’) or two (i.e. ‘bidactyly’) v. (1) one (i.e. ‘monodactyly’).

11/ Apoteles, ungues in adults [A]: (0) three v. (1) two lateral and perfectly symmetrical.

12/ Apoteles, mid ungues [A]: (0) normal v. (1) reduced in size (or ‘Acaronychus-type’ tridactyly).

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