Mesostigmata
Day – 3
Felicity Crotty Mesostigmata
Sejida Trigynaspida Monogynaspida
Cercomegistina Antennophorina Heatherelina Heterozerconina
Microgyniina Uropodina Gamasina
3 Suborders; One main Suborder with 5 Cohorts Trachytidae; Antennophorida; Dithinozerconidae; Epicriidae; Parasitidae Veigaiidae; Ologamasidae; Celaenopsidae Zerconidae Polyaspididae; Rhodacaridae; Protodinychidae; Digamasellidae; Dinychidae; Sejida Macrochelidae; Microgyniidae Trachyuropodidae; Pachylaelapidae; Trematuridae; Eviphididae; Podocinidae; Oplitidae; Laelapidae; 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Bingo I.D character Pedofossa: recesses into which legs can be withdrawn Epicriina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 Oribatida
Desmonomata
Enarthronota Mixonomata Paleosomata Parhyposomata Nothrina Brachypylina Astigmata
“Lower Oribatids” “Higher Oribatids” Macropyline Brachypyline
5 Supercohorts; One with three cohorts Euphthiracarida; Phthiracaridae; Oribotritiidae; Oribotritiidae; Hydrozetidae; Peloppiidae; Autognetidae; Ctenobelbidae; Suctobelbidae; Caleremaeidae; Micreremidae; Amerobelbidae; Oppiidae; Scutoverticidae; Cepheidae; Tectocepheidae; Carabodidae; Thyrisomidae; Astegistidae; Cepheidae; Quadroppidae; 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. Adelphacaridae; Palaeacaridae = 64 FAMILIES Defining characters of the 6 major Oribatid groups
Character Palaeosomata Enarthronota 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 mites 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 Astigmatina (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; Histiostomatidae; Astegistidae; Winterschmidtiidae; Cepheidae; Quadroppidae; Glycophagidae; Hermanneiellidae; Acaridae ; 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 mite, it is • Rhizoglyphus very easy to identify to family AND If you are • Glycyphagus feeling adventurous, you • Lepidoglyphus can also key to genera! • Histiostoma Prostigmata
Day – 3
Felicity Crotty
Labidostommatidae; Cryptognathidae; Eriophyoidea; Penthalodidae; Scutacaridae; Tarsonemidae; Pygmephoridae; Acarophenacidae; Calyptostomatidae; Microtrombidiidae; Smarididae; Erythraeidae; Tanaupodidae; Johnstonianidae; Eutrombidiidae; Trombidiidae; Trombidulidae; Anystidae; Cheyletidae; Stigmaeidae; Bdellidae; Cunaxidae; Eupodidae; Penthaleidae; 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 Parasitengona 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