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Soil Acarology (Mites). Day – 3 Felicity Crotty. >30 taxa. But mostly unknown. Estimated, undescribed species. Species number. Known species. 10 000 000. 75 %. 1 000 000. NE. 83 %. 97 %. 72 %. 100 000. 99 %. 41 %. NE. 52 %. NE. NE. 99 %. 47 %. 10 000. NE. 54 %. 50 %.
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Soil Acarology (Mites) Day – 3 Felicity Crotty
>30 taxa
But mostly unknown... Estimated, undescribed species Species number Known species 10 000 000 75 % 1 000 000 NE 83 % 97 % 72 % 100 000 99 % 41 % NE 52 % NE NE 99 % 47 % 10 000 NE 54 % 50 % NE 1000 75 % NE NE 208 300 60 000 NE 25 000 100 9539 10 000 8800 9260 5000 6500 5000 3627 2500 1600 1500 773 730 600 162 160 10 70 56 1 Acari Diptera Isoptera Diplura Isopoda Araneae Sqamata Protozoa Mollusca Symphyla Caecilian Nematoda Coleoptera Diplopoda Chilopoda Collembola Oligochaeta Mammalia Formicoidea Enchytraeidae Other Arachnida Body size Source: Decaëns et al. (2006)
What is a Mite?!? Tiny but diverse arachnids related to spiders, are some of the most abundant and diverse groups of invertebrate fauna. Found in all environments worldwide, from the deserts to the polar regions and everything in between . The are predators, fungivores, detritivores and even herbivores. Thus occupying many different niches and speciating to adapt to the ecosystem they are inhabiting
Sub-Class Acari Super-Order Parasitiformes Acariformes Trombidiformes Holothrida Mesostigmata Sarcoptiformes Ixodida Opilloacarida Order Sphaerolichida Endeostigmata Monogynaspida Trigynaspida Prostigmata Oribatida Sub-Order Sejida Palaeosomata Eupodides Parhyposomata Labidostommatides Enarthronota Anystides Super-Cohort Eleutherengonides Brachypylina Desmonomata Mixonomata Astigmata Cercomegistina Microgynina Raphignathina Uropodina Anystina Cohort Heterozerconina Heterostigmata Antennophorina Heatherellina Parasitengonina Gamasina Euptyctima Epicriiae Pycnonticae Sub-Cohort / Infra-Order Arctacariae Dichosomata Poronoticae Dermanyssiae Parasitiae
Parasitiformes Holothyrida Opilioacaridae Mesostigmata Ixodidae • Look superficially like harvestmen • Found in caves, also under rocks and litter • Moderately rare • 6 genera; 20 species • In leaf litter, mosses and under stones in moist forests • rare • Families: - Holothyridae - Allothyridae - Neothyridae • Cosmopolitan • Most free living predators • Suborders: - Sejida - Trigynaspida - Monogynaspida • Obligate blood sucking parasites • Common • Families: - Ixodidae (Hard) - Argasidae (Soft) - Nuttalliellidae
Parasitiformes Holothyrida Opilioacaridae Mesostigmata Ixodidae • Look superficially like harvestmen • Found in caves, also under rocks and litter • Moderately rare • 6 genera; 20 species • In leaf litter, mosses and under stones in moist forests • rare • Families: - Holothyridae - Allothyridae - Neothyridae • Cosmopolitan • Most free living predators • Suborders: - Sejida - Trigynaspida - Monogynaspida • Obligate blood sucking parasites • Common • Families: - Ixodidae (Hard) - Argasidae (Soft) - Nuttalliellidae
Acariformes Sarcoptiformes (Oribatida) Trombidiformes (Prostigmata) Mostly Prostigmata (Sphaerolichida also a suborder in this group) Prostigmata with five supercohorts (variable family number within) Extremely common Mixture of predators and herbivores/fungivores Many have a phoretic immature stage “chiggers” • Mostly Oribatids (Endeostigmata also a suborder in this group and Astigmata a cohort within Oribatida) • Oribatids four supercohorts considered “lower” oribatids – MACROPYLINE one supercohort considered “higher” – BRACHYPYLINE • Extremely common
Mite Ecology Day – 3 Felicity Crotty
Almost nothing known of the biology and basic needs of most native species
Cyclic interactions Greater plant yield (more litter produced) More efficient moisture and nutrient uptake Improved rooting More food for soil biota Improved habitat for soil biota Improved soil structure Improved nutrient cycling Improved water regulation van Eekeren, Murray & Smeding (2007)
Rhizophagous aphids Collembola Predaceous mites Cryptostig. mites Phytophagous nematodes Predaceous collembola Roots Non-cryptostig. mites Nematode feeding mites Fungivorous nematodes Fungi Predaceous nematodes Earthworms Detritus Enchytraeids Bacteria Bacteriophagous nematodes Winter Wheat fields: Netherlands Amoebae Flagellates Adapted from De Ruiteret al. (1993) J. Appl. Ecol. 30, 95-106 Blue = Bacterial Green = Fungal Red = Root Bacteriophagous mites
Trophic patterns in Acari (rare) (Ticks) (Similar to harvestmen) (mainly predators) (macropyline) (brachypyline)
Feeding strategies Saprophagy (phyllophagy) – using parenchymous tissue of dead leaves Saprophagy (xylophagy) – using woody structural tissue / dead plant parts e.g. Mixonomata species R. Norton R. Norton
Saprophagy (Phyllo / Xylo)Energy Flow DIRECT: Assimilation of energy from plant materials (BUT low quality food – high C:N; produce large faecal pellets – little of C is used) INDIRECT: Production of faecal pellets with greater surface area – “material going through digestive tract of total mite population in 1 year, apx equal to 50% of annual litter fall!” Berthet 1964 DIRECT: Assimilation of nutrients from plant materials; Concentration of nutrients (and heavy metals) INDIRECT: Shredding increases nutrient leaching Nutrient Cycling
Feeding strategies Mycophagy – feeding on fungal hyphae or spores (usually growing on decaying plant material) Other strategies include: Necrophagy Coprophagy Bacteriophagy Nematophagy Protistivory Herbivory (root / living tissue) Algivory Omnivory Predation
Mycophagy / BacteriophagyEnergy Flow DIRECT: Assimilation of energy from microflora INDIRECT: Stimulation / suppression of microfloral activities. Dispersal of hyphae/spores. Selective grazing. DIRECT: Assimilation of nutrients from plant materials; Concentration of nutrients (and heavy metals) INDIRECT: Stimulation or suppression of microfloral activities Nutrient Cycling
Aboveground communities are affected by both direct and indirect consequences of soil food web.- Indirect (R) detritus food web stimulate nutrient turnover improving plant performance.- Direct (L) soil biota feed on roots and form antagonistic / mutualistic relationships Wardle et al., Science 2004
Microhabitats • Burrowers • Soil dwellers • Lichen associates • Saxicoles (rock dwellers) • Arboreal – “island soil colonies” • Marine littoral • Fresh water • Insect Associates
Biology • The majority of the Mesostigmata and Prostigmata are r-strategists with fast reproductive cycles, short lifespans and quick recovery times to perturbations • Majority of the Oribatids are k-strategists with slow reproductive cycles, long lifespans and are slow to recover to perturbations – may therefore be a good indication group
Mite Glossary http://itp.lucidcentral.org/id/mites/invasive_mite/Invasive_Mite_Identification/key/0_Glossary/Mite_Glossary.htm
JARGON Body Regions Different order = different words OR even different key Prosoma = front body - carapace? - prodorsal - pronotal ≠ notum = back - podonotal Opisthosoma= back body - Opisthonotal - Opisthogaster (gaster = stomach) • -soma = body • Pro- = front • Opistho- = back • Podo- = foot • Gnatho- = jaw/mouth/head • Idio- = distinct / unique
Mite arbitrary body divisions (JARGON) Mouth parts/head Gnathosoma(sometimes referred to as capitulum) Proterosoma (Anterior of sejugal furrow) Prosoma (= cephalothorax) Aspidosoma is anterior dorsal region Propodosoma (dorsal surface = prodorsum) Legs I & II Podosoma Hysterosoma (Rear of sejugal furrow) Dorsally called notogaster Metapodosoma Legs III & IV Idiosoma (body) Gaster if ventral or notum if dorsal Abdomen region Opisthosoma (Opisthonotal if dorsal)
JARGON… It’s getting “trichy” - CHAETOTAXY (setal position / hairs) • Holotrichy – complete complement of setae thought to be present in ancestral group - Unideficient – lost one setae (f1) • Neotrichy – setae not in ancestral condition (new hairs) • Hypertrichy – extra setae