Transcript Soil mites
Soil Acarology (Mites) Day – 3 Felicity Crotty >30 taxa But mostly unknown... Estimated, undescribed species Species number Known species NE 10 000 1000 NE NE 75 % 56 162 773 100 3627 70 208 300 9539 9260 10 000 100 000 52 % NE NE 83 % NE 1 000 000 NE 2500 41 % NE 5000 1600 60 000 600 8800 47 % 50 % NE 160 730 6500 25 000 54 % 72 % 97 % 99 % 1500 5000 99 % 75 % 10 000 000 10 1 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 Order Parasitiformes Holothrida Opilloacarida Trigynaspida Acariformes Mesostigmata Sub-Order Sphaerolichida Endeostigmata Monogynaspida Palaeosomata Eupodides Parhyposomata Labidostommatides Enarthronota Cohort Microgynina Eleutherengonides Brachypylina Astigmata Uropodina Heterostigmata Antennophorina Sub-Cohort / Infra-Order Arctacariae Parasitengonina Gamasina Euptyctima Epicriiae Parasitiae Raphignathina Anystina Heterozerconina Heatherellina Anystides Desmonomata Mixonomata Cercomegistina Prostigmata Oribatida Sejida Super-Cohort Trombidiformes Sarcoptiformes Ixodida Dermanyssiae Dichosomata Pycnonticae Poronoticae Parasitiformes Mesostigmata Holothyrida • In leaf litter, • Cosmopolitan mosses and • Most free living under stones in predators moist forests • Suborders: • rare - Sejida • Families: - Trigynaspida - Holothyridae - Monogynaspida - Allothyridae - Neothyridae Ixodidae Opilioacaridae • Obligate blood sucking parasites • Common • Families: - Ixodidae (Hard) - Argasidae (Soft) - Nuttalliellidae • Look superficially like harvestmen • Found in caves, also under rocks and litter • Moderately rare • 6 genera; 20 species Parasitiformes Mesostigmata Holothyrida • In leaf litter, • Cosmopolitan mosses and • Most free living under stones in predators moist forests • Suborders: • rare - Sejida • Families: - Trigynaspida - Holothyridae - Monogynaspida - Allothyridae - Neothyridae Ixodidae Opilioacaridae • Obligate blood sucking parasites • Common • Families: - Ixodidae (Hard) - Argasidae (Soft) - Nuttalliellidae • Look superficially like harvestmen • Found in caves, also under rocks and litter • Moderately rare • 6 genera; 20 species Acariformes Sarcoptiformes (Oribatida) • 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 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” 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 Phytophagous nematodes Roots Collembola Cryptostig. mites Non-cryptostig. mites Fungi Fungivorous nematodes Earthworms Detritus Predaceous mites Predaceous collembola Nematode feeding mites Predaceous nematodes Enchytraeids Bacteria Winter Wheat fields: Netherlands Adapted from De Ruiter et al. (1993) J. Appl. Ecol. 30, 95-106 Bacteriophagous nematodes Flagellates Bacteriophagous mites Amoebae Blue = Bacterial Green = Fungal Red = Root Trophic patterns in Acari Feeding strategies Saprophagy (xylophagy) – using woody structural tissue / dead plant parts e.g. Mixonomata species Saprophagy (phyllophagy) – using parenchymous tissue of dead leaves 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 Nutrient Cycling DIRECT: Assimilation of nutrients from plant materials; Concentration of nutrients (and heavy metals) INDIRECT: Shredding increases nutrient leaching 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 / Bacteriophagy Energy Flow DIRECT: Assimilation of energy from microflora INDIRECT: Stimulation / suppression of microfloral activities. Dispersal of hyphae/spores. Selective grazing. Nutrient Cycling DIRECT: Assimilation of nutrients from plant materials; Concentration of nutrients (and heavy metals) INDIRECT: Stimulation or suppression of microfloral activities Functional groups of mites (cf. Moore et al. 1988) Functional Group Description Taxa General predators Attack anything smaller Mesostigmata Arthropod predators Attack only Arthropods Many Prostigmata Nematode Predators Only nematodes Mesostigmata Some Oribatida Fluid feeding fungivore Pierce and suck fluids of fungi, protists Prostigmata Engulfing fungivores Ingest bits of fungi, hyphae, algae, spores Oribatida Astigmata Root fluid feeders (Herbivores) Pierce roots and suck fluids Some Prostigmata Detritivores Ingest dead plant material Oribatida Astigmata Coprophagous Ingest faecal / exoskeleton material Oribatida Astigmata 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/mi tes/invasive_mite/Invasive_Mite _Identification/key/0_Glossary/ Mite_Glossary.htm JARGON Body Regions • • • • • • -soma = body Pro- = front Opistho- = back Podo- = foot Gnatho- = jaw/mouth/head Idio- = distinct / unique Different order = different words OR even different key • Prosoma = front body - carapace? - prodorsal - pronotal ≠ notum = back - podonotal • Opisthosoma = back body - Opisthonotal - Opisthogaster (gaster = stomach) Mite arbitrary body divisions (JARGON) Mouth parts/head Legs I & II Legs III & IV Abdomen region Gnathosoma (sometimes referred to as capitulum) Propodosoma (dorsal surface = prodorsum) Podosoma Proterosoma Prosoma (= cephalothorax) Aspidosoma is anterior dorsal region Metapodosoma Idiosoma (body) Opisthosoma (Opisthonotal if dorsal) Gaster if ventral or notum if dorsal (Anterior of sejugal furrow) Hysterosoma (Rear of sejugal furrow) Dorsally called notogaster 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