Smith, I.M., Lindquist, E.E., and V. Behan-Pelletier. 1998. Mites (Acari) in Smith, I.M., and G.G. Scudder, eds. Assessment of species diversity in the Montane Cordillera Ecozone. Burlington: Ecological Monitoring and Assessment Network, 1998.

MITES (ACARI)

Ian M. Smith, Evert E. Lindquist and Valerie Behan-Pelletier

ACARIFORMES - ORIBATIDA - V.M. Behan-Pelletier

In the Montane Cordillera, as in all terrestrial ecosystems, Oribatida, the so called "beetle" or "box" mites, are actively involved in decomposition of organic matter, in nutrient cycling and in soil formation. All active instars of these mites feed on a wide variety of material including living and dead plant and fungal material, lichens and carrion; some are predaceous, but none is parasitic. Oribatida influence decomposition and soil structure by shredding and feeding on organic matter and producing faecal pellets, which provide a large surface area for primary decomposition by bacteria and fungi, and which are in turn an integral component of soil structure. Oribatida also disperse bacteria and fungi, both externally on their body surface, or by feeding, with subsequent survival of spores during passage through their alimentary tracts. Many oribatid species sequester calcium and other minerals in their thickened cuticle. Thus, their bodies may form important 'sinks' for nutrients, especially in nutrient limited environments (Crossley 1977, Norton and Behan-Pelletier 1991), or in areas of heavy metal contamination (Streit 1984). Recently, research has focussed on the role of oribatid mites in bioremediation and biomonitoring and their role as bioindicators in soil (van Straalen and Verhoef 1997), all of critical importance in the Montane Cordillera Ecozone. Recent reviews on the role of Oribatida in decomposition and nutrient cycling include those of Wallwork (1983), Seastedt (1984) and Norton (1986).
 
Oribatid mites have six postembryonic instars: an inactive prelarva, and active larva, protonymph, deutonymph, tritonymph and adult. All active stages feed, and feeding habits may differ between immatures and adult of the same species (Siepel 1990). Oribatid mites generally have low metabolic rates, slow development and low fecundity and exemplify "k-selected" organisms (Crossley 1977). Species are iteroparous with adults living a relatively long time (Norton 1993). Estimates of development time from egg to adult vary from several months to two years in temperate forest soils (Luxton 1981). In cool climates oribatid mites have longer life cycles. For example, Tectocepheus velatus (Michael) from northern Norway live for two or more years (Solhøy 1975). Data from Burn (1986) suggest that the duration of nymphal stages of the Antarctic species Alaskozetes antarcticus (Michael) may be more than three years.
 
Oribatid mites in temperate and cold habitats, such as the alpine in Montane Cordillera, exhibit extensive supercooling ability (Sømme 1981). In all species studied immature stages are at least as cold hardy as adults (Cannon 1987) and immatures and adults can overwinter in mixed populations (Cannon and Block 1988). Oribatida in temperate and cold habitats also have cold tolerance traits such as accumulation of cryoprotections and resistance to desiccation, but data suggest that these traits are plesiotypic rather than adaptive in Oribatida (Behan-Pelletier 1998).
 
Knowledge of oribatid species richness in the Montane Cordillera is based on surveys by taxonomists in the Kananaskis Region, Waterton Lakes National Park, Haynes Lease Ecological Reserve and surrounding arid grassland communities, Cathedral Provincial Park and Manning Provincial Park, voucher specimens for which are in the Canadian National Collection of Acari, and ecological research studies in the Kananaskis Region (Mitchell 1977; Mitchell and Parkinson 1976; McLean et al. 1996; Kaneko et al. 1995), and in Kamloops (Marshall 1979b).
 
The known oribatid fauna of the Montane Cordillera has been collected mainly in the foothills of the Rocky Mountains, in arid grasslands, and in alpine habitats in Manning and Cathedral Provincial Parks. Berlese extraction of soil and litter was the method of collecting mites used in all studies, and thus arboreal oribatid species and deep soil species have been ignored. As many species of Oripodoidea are arboreal, this potentially explains the poor representation of this superfamily in the ecozone. Techniques such as deep soil washing and heptane flotation, or twig washing have not been used in habitats in the Montane Cordillera; similarly, few aquatic habitats have been sampled. Oribatid species richness in the arid grassland communities of the southern Okanagan is low in comparison with that of forested habitats in the Ecozone where more than 50 species may be found in a single sample of 100 cm3. However, it compares favourably with data from semi-arid grasslands in Colorado (Walter 1987) and desert and semi-desert habitats in New Mexico (Kamil et al. 1985).
 
The suborder Oribatida, (Oribatei or Cryptostigmata), is represented in Canada by 31 superfamilies, many of which occur in the Montane Cordilleran Ecozone. The Canadian fauna was treated at the family level by Marshall (1979a), and published distribution records for species known from Canada were given in Marshall et al. (1987) and Behan-Pelletier (1993a). Expected species diversity in families represented in the Montane Cordillera is presented in Table 3. Known species diversity of oribatid mites in the Montane Cordilleran Ecozone, based on published records, is presented in Table 4, the distribution of these species in the Montane Cordillera and the Ecological Regions of North America is summarized in Table 5.
 
TABLE 3: EXPECTED DIVERSITY OF FAMILIES OF ORIBATIDA KNOWN FROM THE MONTANE CORDILLERA ECOZONE BASED ON RECORDS OF NAMED AND UNNAMED SPECIES IN CANADIAN NATIONAL COLLECTION OF ACARI
 

SUPERFAMILY	FAMILY	HABITAT OR HOST OF ADULT	FEEDING BEHAVIOUR OF ADULT	# SPECIES EXPECTED IN MONTANE CORDILLERA/ CANADA
Palaeacaroidea	Palaeacaridae	soil, litter	fungivorous, algivorous	1/3
Ctenacaroidea	Aphelacaridae	soil	fungivorous, algivorous	1/1
canadensis Hypochthonioidea	Hypochthoniidae	litter	fungivore, saprophagous	1/2
	Eniochthoniidae	soil, litter	fungivorous	1/2
	Mesoplophoridae	litter, decaying wood	saprophagous	2/5
Protoplophoroidea	Cosmochthoniidae	moss, lichen, litter	algivorous	3/5
Unplaced Family	Arborichthoniidae	moss, litter	unknown	1/1
Brachychthonioidea	Brachychthoniidae	moss, soil, litter, lichens	fungivorous, algivorous	20/50
Atopochthonioidea	Atopochthoniidae	soil, litter	unknown	1/3
Parhypochthonioidea	Parhypochthoniidae	soil	unknown	1/1
	Gehypochthoniidae	soil	unknown	1/1
Phthiracaroidea	Phthiracaridae	decaying wood, litter	saprophagous (xylophagous)	10/25
Euphthiracaroidea	Oribotritiidae	decaying wood, litter	saprophagous (xylophagous)	5/10
	Euphthiracaridae	decaying, wood, litter	saprophagous (xylophagous)	5/10
Eulohmannioidea	Eulohmanniidae	soil, litter	unknown	1/1
Epilohmannioidea	Epilohmanniidae	litter, moss	unknown	3/4
Crotonioidea	Nothridae	moss, litter	sapropagous	4/8
	Camisiidae	moss, litter, canopy, semiaquatic	saprophagous	5/25
	Trhypochthoniidae	moss, litter, semiaquatic, aquatic	fungivorous, algivorous	5/10
	Malaconothridae	moss, litter, semiaquatic	fungivorous, algivorous	4/10
Nanhermannioidea	Nanhermanniidae	moss	fungivorous	2/10
Hermannioidea	Hermanniidae	moss	fungivorous	4/8
Hermannielloidea	Hermanniellidae	moss, litter	fungivorous, saprophagous	4/8
	Plasmobatidae	moss, litter	unknown	1/1
Liodoidea	Liodidae	moss, canopy	saprophagous	2/4
Plateremaeoidea	Gymnodamaeidae	dry litter	fungivorous, saprophagous	10/25
	Plateremaeidae	dry litter, moss	unknown	1/2
	Licnodamaeidae	moss, litter	unknown	1/2
Damaeoidea	Damaeidae	moss, litter	fungivorous	20/50
Polypterozetoidea	Podopterotegaeidae	litter	unknown	1/2
Cepheoidea	Cepheidae	moss, litter	saprophagous	5/20
Microzetoidea	Microzetidae	litter	unknown	2/2
Amerobelboidea	Amerobelbidae	litter	unknown	1/1
	Eremulidae	litter	unknown	1/2
	Damaeolidae	litter	unknown	1/1
	Eremobelbidae	litter	unknown	1/3
Eremaeoidea	Eremaeidae	litter, moss, lichen	fungivorous	20/35
	Megeremaeidae	litter, moss	fungivorous	3/6
Zetorchestoidea	Zetorchestidae	moss	fungivorous	1/1
Gustavioidea	Tenuialidae	moss	unknown	5/10
	Liacaridae	moss, litter	saprophagous	10/25
	Astegistidae	moss, litter	fungivorous	5/10
	Peloppiidae	moss, litter	fungivorous	8/25
	Gustavioidea	moss, litter	unknown	1/3
	Kodiakellidae	moss, litter	unknown	0/1
Carabodoidea	Carabodidae	fungi, litter, decaying wood	fungivorous	5/25
Tectocepheoidea	Tectocepheidae	litter	fungivorous	2/4
Oppioidea	Oppiidae	soil, litter	fungivorous	20/80
	Caleremaeidae	soil, litter	unknown	1/3
	Suctobelbidae	soil, litter	fungivorous	15/45
	Autognetidae	soil, litter	fungivorous	4/10
	Thyrisomidae	soil, litter, moss	fungivorous	8/15
	Quadroppiidae	soil, litter	fungivorous	2/5
Hydrozetoidea	Hydrozetidae	aquatic	algivorous, fungivorous	2/8
	Limnozetidae	aquatic, semiaquatic	algivorous, fungivorous	2/20
Ameronothroidea	Ameronothridae	semiaquatic	unknown	1/6
	Tegeocranellidae	semiaquatic	fungivorous	1/4
Cymbaeremaeoidea	Cymbaeremaeidae	dry litter	fungivorous	10/20
	Micreremidae	litter	unknown	1/1
Licneremaeoidea	Licneremaeidae	canopy	unknown	1/2
	Passalozetidae	dry litter	fungivorous	2/4
	Scutoverticidae	dry litter	unknown	2/5
Oripodoidea	Parakalummnidae	litter	saprophagous	4/12
	Scheloribatidae	soil, litter, canopy	fungivorous, predaceous, saprophagous	12/40
	Oribatulidae	soil, litter, canopy	fungivorous	20/35
	Haplozetidae	litter	fungivorous, omnivorous	10/35
	Mochlozetidae	canopy	saprophagous	2/5
	Oripodidae	canopy	fungivorous	10/20
Ceratozetoidea	Chamobatidae	semiaquatic, moss	saprophagous	2/6
	Euzetidae	semiaquatic	saprophagous	1/3
	Zetomimidae	aquatic, semiaquaic	fungivorous, saprophagous	3/6
	Ceratozetidae	litter	saprophagous, fungivorous, predaceous	25/60
	Mycobatidae	moss, litter	fungivorous, saprophagous	10/30
	Humerobatidae	canopy	fungivorous, algivorous, ?predaceous	2/5
Phenopelopoidea	Phenopelopidae	litter	saprophagous	8/25
	Unduloribatidae	litter	unknown	1/2
Oribatelloidea	Oribatellidae	litter, moss	saprophagous	5/15
Achipterioidea	Achipteriidae	litter, moss	saprophagous	10/40
	Tegoribatidae	litter, moss	saprophagous	10/25
Gaumnoidea	Galumnidae	litter, moss	saprophagous, predaceous	5/25
TOTALS: 31 Superfamilies	80 Families			404/1081

 
There are published records of only 87 species, representing 47 genera and 26 families of oribatid mites from the Montane Cordillera, though this undoubtedly is one of the most diverse ecozones in Canada. I estimate that that these 87 species represent at most 20% of expected diversity (Table 3). For example, there are no representatives of the superfamilies Phthiracaroidea, Euphthiracaroidea, Cepheoidea or Galumnoidea from this Ecozone in publications, and I anticipate many new records in the Brachychthonioidea, Plateremaeoidea, Gymnodamaeoidea, Oppioidea and Ceratozetoidea. Superfamilies with several species represented in the Montane Cordillera, or those of special interest are discussed below.
 
Eremaeoidea: Species in this superfamily primarily are found in dry habitats where they live in organic litter. They are also found on trunks and in the canopy of trees, where they feed on the fungal fruiting bodies and the fungal component of lichens. In the soil profile, species of Eremaeidae are found primarily in the litter layer, or in moss and lichens on the soil surface. Occasionally a large percentage of the population may be found in the fermentation layer (Mitchell 1978), but there is no seasonal pattern of vertical migration, and no significant correlation between soil moisture and horizontal distribution.
 
Most North American species of Eremaeidae prefer dry habitats. Apparently these habitats need to be well structured and/or stable, because only one species has ever been recorded from cultivated soil. In any particular habitat up to five species of Eremaeidae may co-occur. Thus, the few studies on ecology of these genera are clouded because the "Eremaeus sp." in literature generally refers to more than one species (Behan-Pelletier 1993b). Whether size patterns or other character displacements exist in such sympatric congeners, has yet to be determined. Likewise, we know nothing about resource partitioning among these co-occuring fungivores.
 
Species of Eremaeidae are known fungivores (Mitchell and Parkinson 1976). These authors found that in culture Eremaeus spp. would feed only on Phoma exigua Desm. of seven species of fungi offered. They found gut contents of field populations full of other species of fungi. In addtion, pollen grains of conifers were noted in the gut of specimens of Eueremaeus chiatous (Behan-Pelletier 1993b).
 
Overall diversity of Eremaeidae is strikingly higher in the west and southwest of North America, reflecting the habitat requirements of members of this family, and the greater habitat diversity in the western mountains and valley grasslands of the Cordillera. As the oribatid fauna of these regions is known very incompletely, further collecting should uncover many undescribed species, as well as better circumscribe the known distributions of habitats of previously described species. Some species, e.g., Eremaeus boreomontanus, E. kananaskis, E. salish have a distribution restricted to the Western Cordillera, whereas E. plumosus and Eueremaeus osoyoosensis are found in both the Western Crodillera and the Western Interior Basin and Ranges (Table 5).
 
Carabodoidea: Many species in the carabodoid genus Carabodes are more common on tree trunks and in the crown of trees than in litter. They form part of the diverse, but poorly known, arboreal oribatid fauna (Walter and Behan-Pelletier 1998), which includes species in other superfamilies, e.g., Crotonioidea and Oripodoidea. Carabodes species feed on fungi, especially bracket fungi, and lichens on trunks and branches of trees (Reeves 1988). Carabodes wonalancetanus has a wide distribution, but C. colorado and C. dickinsoni have a narrow distribution in the Western Cordillera and the Western Interior Basin and Ranges with the most northerly distribution records from the Montane Cordillera Ecozone (Reeves and Behan-Pelletier 1998).
 
Cymbaeremaeoidea: Species in the cymbaeremaeid genus Ametroproctus are restricted to dry, primarily alpine habitats in western North America, the Russian Far East, Japan, and Switzerland (Behan-Pelletier 1987a). These species are probably fungivorous. In some habitats, e.g., the south-facing aspect of the outcrop at the summit of Kobau Mountain in the Southern Interior they can be the numically dominant oribatid mite. Kobau Mountain has a complex oribatid fauna including species usually found in dry subalpine habitats together with those typically living in grassland. Until recently, Scapuleremaeus kobauensis was only known from this locality in the Southern Interior, but recently has been collected from a similar, arid habitat in California.
 
Licneremaeoidea: The scutoverticid species Exechocepheus eremitus Woolley and Higgins is among the dominant arthropods and often the dominant oribatid mite in grass habitats in the Haynes Lease Ecological Reserve in Okanagan Highlands Ecoregion, and on Kobau Mountain (Behan-Pelletier 1987b). This species is also known from shortgrass prairie sites at Writing-on-Stone Provincial Park, Alberta. Occurrence of this genus in Canada is so far restricted to these dry to arid grassland habitats. Another interesting record is the occurrence of Passlaozetes californicus Wallwork in soil under Agropyron spicatum at Haynes Lease Ecological Reserve. This species was first described from Joshua Tree National Monument in California, and has subsequently been found in semi-desert soils in New Mexico. Their presence in the Reserve is the most northerly record for both these species.
 
Ceratozetoidea: This is diverse superfamily in the Montane Cordillera, the fauna being dominated by members of the Ceratozetidae and Mycobatidae which prefer dry habitats, the habitats which have been best surveyed in this Ecozone. Undoubtedly, collecting in aquatic habitats in this Ecozone will yield species of the ceratozetoid family Zetomimidae which live in semi-aquatic habitats. Species of Ceratozetes, Dentizetes and Mycobates are macrophytophages, microphytophages, fungivores; some feed on carrion. Ceratozetes kananaskis, C. oresbios, C. watertonensis and M. brevilamellatus are only known from the Montane Cordillera (Behan- Pelletier 1993a), whereas M. altus also has been recorded from the Southern Cordillera site at Niwot Ridge in Colorado (Behan-Pelletier 1994). Interestingly, the most southern distribution for D. rudentiger is in the Montane Cordillera. Species of Ceratozetidae are among the oribatid mites of veterinary importance as intermediate hosts and vectors of tapeworms, and could play a similar role as intermediate hosts for tapeworms of Mountain goats.
 

TABLE 4: LIST OF NAMED SPECIES OF ORIBATID MITES FROM THE MONTANE CORDILLERA ECOZONE (Unnamed species included are only known representatives of genus in Ecozone)

Superfamily - Brachychthonioidea

Family - Brachychthoniidae

Brachychthonius bimaculatus Willmann

Liochthonius lapponicus Trägårdh

Sellnickochthonius immaculatus (Forsslund)

Verachthonius montanus (Hammer)

Superfamily - Protoplophoroidea

Family - Cosmochthoniidae

Cosmochthonius sp.

Superfamily - Crotonioidea

Family - Camisiidae

Camisia biurus (C. L. Koch)

Camisia horrida (Hermann)

Family - Trhypochthoniidae

Trhypochthonius tectorum (Berlese)

Mucronothrus nasalis (Willmann)

Superfamily - Plateremaeoidea

Family - Gymnodamaeidae

Gymnodamaeus bicostatus (C.L. Koch)

Odontodamaeus sp.

Joshuella sp.

Nortonella gildersleeveae (Hammer)

Superfamily - Damaeoidea

Family - Damaeidae

Belba sp.

Epidamaeus sp.

Dyobelba sp.

Hungarobelba sp.

Quatrobelba montana Norton

Superfamily - Eremaeoidea

Family - Eremaeidae

Eremaeus boreomontanus Behan-Pelletier

Eremaeus kananaskis Behan-Pelletier

Eremaeus occidentalis Behan-Pelletier

Eremaeus plumosus Woolley

Eremaeus salish Behan-Pelletier

Eremaeus translamellatus Hammer   

Eueremaeus aysineep Behan-Pelletier

Eueremaeus chiatous (Higgins)

Eueremaeus foveolatus Hammer   

Eueremaeus marshalli Behan-Pelletier

Eueremaeus masinasin Behan-Pelletier

Eueremaeus michaeli Behan-Pelletier

Eueremaeus osoyoosensis Behan-Pelletier

Eueremaeus tetrosus (Higgins)   

Family - Megeremaeidae

Megeremaeus kootenai Behan-Pelletier

Superfamily - Gustavioidea

Family - Tenuialidae

Hafenferrefia sp.

Family - Liacaridae

Dorycranosus sp.

Family - Peloppiidae

Ceratoppia bipilis (Hermann)

Ceratoppia quadridentata arctica Hammer

Superfamily - Carabodoidea

Family - Carabodidae

Carabodes colorado Reeves & Behan-Pelletier

Carabodes dickinsoni Reeves & Behan-Pelletier

Carabodes wonalancetanus Reeves

Superfamily - Tectocepheoidea

Family - Tectocepheidae

Tectocepheus velatus (Michael)

Superfamily - Oppioidea

Family - Oppiidae

Microppia simplissimus (Jacot)

Oppia sp.

Oppiella washburni (Hammer)

Oppiella nova (Oudemans)

Family - Quadroppiidae

Quadroppia ferrumequina Jacot

Family - Suctobelbidae

Suctobelba sp.

Suctobelbella sp.

Family - Caleremaeidae

Veloppia kananaskis Norton

Superfamily - Cymbaeremaeoidea

Family - Cymbaeremaeidae

Ametroproctus tuberculosus Behan-Pelletier

Ametroproctus reticulatus Aoki & Fujikawa

Ametroproctus canningsi Behan-Pelletier

Scapuleremaeus kobauensis Behan-Pelletier

Superfamily - Licneremaeoidea

Family - Passalozetidae

Passalozetes californicus Wallwork

Family - Scutoverticidae

Exochocepheus eremitus Woolley and Higgins

Superfamily - Oripodoidea

Family - Scheloribatidae

Liebstadia similis (Michael)

Scheloribates pallidulus (C. L. Koch)

Family - Oribatulidae

Oribatula sp.

Zygoribatula sp.

Superfamily - Ceratozetoidea

Family - Ceratozetidae

Ceratozetes cuspidatus Jacot

Ceratozetes gracilis (Michael)

Ceratozetes kananaskis Mitchell

Ceratozetes oresbios Behan-Pelletier

Ceratozetes watertonensis Behan-Pelletier

Ceratozetes thienemanni Willman

Dentizetes rudentiger Hammer

Mycobates altus Behan-Pelletier

Mycobates azaleos Behan-Pelletier

Mycobates brevilamellatus Behan-Pelletier

Mycobates dryas Behan-Pelletier   

Mycobates incurvatus Hammer

Mycobates punctatus Hammer

Superfamily - Phenopelopoidea

Family - Phenopelopidae

Propelops canadensis (Hammer)   

Propelops pinicus Jacot

Superfamily - Oribatelloidea

Family - Oribatellidae

Oribatella sp.

Superfamily - Achipterioidea

Family - Achipteriidae

Lepidozetes sp.

Parachipteria nivalis (Hammer)