Mesostigmata

Day – 3

Felicity Crotty

Sejida Trigynaspida Monogynaspida

Cercomegistina Antennophorina Heatherelina Heterozerconina

Microgyniina Uropodina Gamasina

3 Suborders; One main Suborder with 5 Cohorts Trachytidae; Antennophorida; Dithinozerconidae; Epicriidae; ; Ologamasidae; Celaenopsidae Zerconidae Polyaspididae; Rhodacaridae; Protodinychidae; Digamasellidae; Dinychidae; Sejida Macrochelidae; Microgyniidae Trachyuropodidae; Pachylaelapidae; Trematuridae; Eviphididae; Podocinidae; Oplitidae; ; Amerosidae; Metagynellidae; Phytoseidae; Ascidae Uropodidae 12 families 10 families 6 SEGMENTED LEGS

Leg segmentation Tarsus IV ventral setae av4/pv4 on sclerite between basi and telotarsus a key diagnostic feature!

If present = Sejida or If absent = Trigynaspida Monogynaspida

Generalised venter

• St = sternal shield • Ep = epigynal shield • V = ventral shield • An = anal shield • Mst = metasternal shields • Trt = tritiosternum Hypostomal setae

If linear = Uropodina

If triangular = other cohorts within monogynaspida Uropodid

Bingo I.D character Pedofossa: recesses into which legs can be withdrawn Epicriina

Bingo I.D character Dorsal shield entire, covered with polygonal network of tubercles

Also identifiers include first pair of setae on small platelets. Parasitina

Males have massive arms!! Leg spurs on leg II

Shield character I.D Apex of epigynal shield triangular and flanked by large metasternal shield bearing metasternal setae

Dermanyssina Shields

Oribatida

Day – 3

Felicity Crotty

Desmonomata

Enarthronota Mixonomata Paleosomata Parhyposomata Nothrina Astigmata

“Lower Oribatids” “Higher Oribatids” Macropyline Brachypyline

5 Supercohorts; One with three cohorts Euphthiracarida; Phthiracaridae; Oribotritiidae; Oribotritiidae; ; ; ; ; ; ; ; ; ; ; Cepheidae; ; ; ; Astegistidae; Cepheidae; Quadroppidae; Hermanneiellidae; ; Poroliodidae; ; ; Damaeolidae; Cymbaeremaeid; ; Microzetidae; ; ; ; ; ; Euzetidae; Schleloribatidae; ; Zetomimidae; ; ; Mycobatidae; ; Passlozetidae; Licneremaeidae; Enichthoniidae; ; Atopochthoniidae; ; ; Gehypochthoniidae; ; Gustaviidae; Malaconothrida; Trhypochthoniidae; Eulohmanniidae; Perlohmanniidae; Epilohmanniidae; Nanhermanniidae; Hermanniidae; Camisiidae; . Adelphacaridae; Palaeacaridae = 64 FAMILIES Defining characters of the 6 major Oribatid groups

Character Palaeosomata Parhyposomata Mixonomata Desmonomata & Brachypylina Body weak Weak to Weak to strong Weak to strong Strong Sclerotisation strong Prodorsum Astegasime Steg / Steg / Steg / Stegasime type astegasime astegasime astegasime Body type Dichoid Dichoid / Dichoid / Dichoid / Holoid ptychoid trichoid ptychoid Notogastral Absent or Present (1-3) Present (1) None None Scissures poorly defined Femur Divided fused Fused Fused Fused Opisthosomal Absent Absent Present Present (or Present Gland secondarily lost) Body type

Subcapitulum

Body appears to be divided between legs II-III by a flexible sejugal furrow

Body type

Lacks flexible Box sejugal furrow

3 segments Body type

Fused coxisternum

Postpedal furrow

Pygidium Circumgastric scissure Pronotaspis Body type

2 3 1 View if Oribatid on it’s back STENARTHRIC ANARTHRIC

ANARTHRIC

DIARTHRIC

PELOPSIFORM ATTENUATE- EDENTATE Gnathosoma

Trichobothria First step to identification is it…? Lower Oribatid - Macropyline

• Genua of all legs similar to tibiae in size and shape (not knee-like) • Leg articulation not in deep acetabula • Trochanters I and II small but clearly external. • Paired aggenital and adanal plates often distinguishable • Coxisternal region often transversely divided by sejugal articulation • Subcaptiulum usually stenarthric Higher Oribatid – Brachypyline • Genua of legs I-III (& often IV) shorter than tibiae and lacking intrinsic musculature – KNEE • Holoid body type • Distinct acetubula with trochanters I and II almost totally contained within • Apodemato-acetabular system of tracheae • Brachypyline venter unified rigid plate • Often evolved chelicerae & subcapitulum modified - diarthric Acetabulum is a concave cavity in the body wall where a leg is inserted; in brachypyline oribatids these cavities are where the trochanter articulates with the coxae (fused to body wall) and may contain tracheal stigmata

Genua knee like Examples of different Oribatids

Numbers relate to susceptibility to degraded environments (5 = very susceptible)

Aoki 1996 (or Astigmata in some literature)

Day – 3

Felicity Crotty Euphthiracarida; Phthiracaridae; Oribotritiidae; Oribotritiidae; Hydrozetidae; Peloppiidae; Autognetidae; Ctenobelbidae; Suctobelbidae ; Caleremaeidae; Micreremidae; Amerobelbidae; Oppiidae; Scutoverticidae; Cepheidae; Tectocepheidae; CarabodidaeCanestriniidae; Thyrisomidae; ; Astegistidae; Winterschmidtiidae; Cepheidae; Quadroppidae; Glycophagidae; Hermanneiellidae; ; Damaeidae; Poroliodidae; Eremaeidae ; Ameronothridae; Damaeolidae; Cymbaeremaeid; Galumnidae; Microzetidae; Achipteriidae; Haplozetidae; Phenopelopidae ; Oribatellidae; Ceratozetidae; Euzetidae; Schleloribatidae; Oribatulidae; Zetomimidae; Limnozetidae; Humerobatidae ; Mycobatidae; Chamobatidae; Passlozetidae; Licneremaeidae; Enichthoniidae; Hypochthoniidae; Atopochthoniidae ; Cosmochthoniidae; Brachychthoniidae; Gehypochthoniidae; Liacaridae; Gustaviidae; Malaconothrida; Trhypochthoniidae ; Eulohmanniidae; Perlohmanniidae; Epilohmanniidae; Nanhermanniidae; Hermanniidae; Camisiidae; Nothridae . Astigmatina

• Cohort of Oribatida (in Desmonomata currently) • Weakly sclerotized (white / pale) • Slow moving • Lack respiratory stigmata or tracheae (respire through cuticle) • Lack segmentation • Body divided into 2 main regions gnathosoma and idiosoma (separated by sejugal furrow) Astigmatina Astigmatina

• Palps ONLY 2 segmented • Chelicerae are chelate-dentate (3) • Have two genital papillae (4) • Male has aedeagus (4) • Anal opening often flanked by copulatory suckers (6) • A claw at apex of tarsus attached to a fleshy pretarsus, supported by sclerotised condylophores (7) Astigmatina biology • Complete life cycle in several days to weeks • Lay up to 800 eggs in a month! • Adult average longevity 23-46 days • Have an unusual heteromorphic deutonymphal (often phoretic) • Hypopus – highly resistant to adverse environmental conditions. Lacks mouthparts, often has suckerplate Most important soil genera

• Tyrophagus Once you are certain it is • Schwiebea an Astigmatid , it is • Rhizoglyphus very easy to identify to family AND If you are • Glycyphagus feeling adventurous, you • Lepidoglyphus can also key to genera! • Histiostoma

Day – 3

Felicity Crotty

Labidostommatidae; Cryptognathidae; ; Penthalodidae; Scutacaridae; ; Pygmephoridae; Acarophenacidae; Calyptostomatidae; Microtrombidiidae; ; ; Tanaupodidae; Johnstonianidae; Eutrombidiidae; ; Trombidulidae; Anystidae; ; Stigmaeidae; Bdellidae; Cunaxidae; Eupodidae; ; Rhagidiidae; Erynetidae; Tydaeidae; Iolnidae; Triophytdaeidae; = 29 families in UK

Prostigmata

Eupodides Anystides Eleutherengonides Labidostommatides

Anystina Parasitengonina Raphignathina Heterostigmata

4 Supercohorts; two of which have 2 cohorts within them Comparative Characters Prostigmata

Eupodina Anystid Raphignathae Heterostigmata Palp 4 5 5 5 3 max segments Palp tibia Linear Thumb claw Thumb claw Thumb claw No stigmata Base of Base of Absent Base of Anterior lateral on chelicera chelicera chelicera propodorsoma F Peritremes No Yes No Yes No Naso Yes Yes Yes No No Pairs of 1,2 1 1,2 0 0 imm; 1 F; 0 M trichobothria Empodial No No No Yes No (II, III tenant hairs membraneous) Trichobothria

Eye Dorso-sejugal Suture not distinct Dorso-sejugal suture

Genital papillae

Endeostig

Prostig Examples of palp thumbclaw Peritremes Stigmata

Two different naming systems! Same segmentation on palp

5 free leg segments

Coxa fused to ventral idiosoma Paired claws and empodium Paired claws Solenidia

Different types of setae and Trichobothria (arrow)

Famulus If Solenidia is supposed to be “Recumbent”, it is lying down alongside leg

Duplex setae: Normal setae alongside a Solenidia Labidostomatidae • 1 family • Medium to large sclerotized mites • “Arnie” mite – look like it has a 6 pack! – Coxal fields expanded • 2 pairs prodorsal trichobothria • Palps linear • Cheliceral bases separate, digits enlarged and chelate-dentate • Legs I tactile; legs II-IV walking • Predator Parasitengona • Members of this group are well known to non- acarologists as velvet mites! • Red or green • Stigmata & peritremes located between cheliceral bases • Palp thumbclaw well developed • 1 or 2 prodorsal trichobothria • Genital papillae usually present Heterostigmata • Very common • Minute to medium sized • Capitulum head-like • Palps linear and reduced to 3 or fewer segments • F: stigmata anterolaterally (on shoulders) of prodorsum. • Legs I often with tarsal claw as modified hook • F: legs IV often reduced or absent Major character systems in Prostigmata • Chelicerae modified e.g. fused together / subcapitulum; reduction of fixed digit (Prostigmata are mainly fluid feeders) • Modification of the palp • Body setation • Leg setation • Modification of the pretarsus Acknowledgments

Soil Mite Experts Cal Welbourne Valerie Behan-Pelletier Roy Norton David Walter