Mesostigmata

t

Taxonomy

updated 2025

Diagnostic characters

• Female with schizodorsal or divided dorsal shielddivided dorsal shield:
  in Mesostigmata, adult mites have two usually subequal dorsal shields.
  with setae of dorsal hexagondorsal hexagon:
  a fancied hexagonal area staked out by setal pairs j5, z5 and j6 in the podonotal region of many mesostigmatans; useful for orienting to setae to determine designations (see Lindquist-Evans system);  setae j3-5 may also form a hexagonal array.
  (j5, z5, j6) usually dissimilar (z5 often thickened and distally pilosepilose:
  with a covering of hairs or hair-like processes.
  )
• Genital shieldgenital shield:
  a shield or shields covering the genital opening; in female mongynaspine Mesostigmata this shield is usually called the epigynal (epigynial) shield.  
  +/- triangular, sharply taperingtapering:
  drawn out or with margins converging.
  to a point and flanked by large metasternal shields
• Male with anterior genital aperturegenital aperture:
  the genital opening or acetabulum.
  and distally fused spermatotremespermatotreme:
  a slit-like opening on the movable digit of male Parasitidae that grasps the neck of the spermatophore during sperm transfer; considered to be a foramen left by the distal fusion of a spermatodactyl to the movable digit.
  on chelicerae
• Tibiatibia:
  (pl. tibiae) the leg segment between the genu and the tarsus.
  I usually with 14 setae, including 4 ventralventral:
  relating to the lower or under side; opposed to dorsal.
  and 6 dorsaldorsal:
  relating to the upper or back side; opposed to ventral.
  

Key to some Parasitine genera (adult females) (modified from Hyatt 1980)

1. Lateral setae of palppalp:
   (= pedipalp) the second pair of limbs in arachnids, used in feeding and originating on either side of the chelicerae.  In mites, the palps may be vestigial, with only a few segments, or have a maximum of  5 freely articulating segments (rarely the femur is subdivided) and a distal or subdistal apotele.
   genu (al1–2) entireentire:
   a shield or sclerite with a continuous margin without incisions.
   , either setiform or spatulatespatulate:
   (Latin spatula = spoon) spatula-shaped; variously interpreted, but usually referring to setae that are flattened and somewhat expanded distally.
   .............................. 2
   - Lateral setae of palppalp:
   (= pedipalp) the second pair of limbs in arachnids, used in feeding and originating on either side of the chelicerae.  In mites, the palps may be vestigial, with only a few segments, or have a maximum of  5 freely articulating segments (rarely the femur is subdivided) and a distal or subdistal apotele.
   genu (al1–2) bifid.............................. Eugamasus

2. Posterior ventral regionventral region:
   in Mesostigmata, the area between the genital and anal regions.
   (opisthogaster) with 30 or fewer pairs of setae; associated with a variety of insects, but usually not bumblebees (Bombus).............................. 3
   -  Opisthogaster with extensive hypertrichy (>40 pairs of setae); associated with bumblebees (Bombus) or their nests.............................. Parasitellus

3. Corniculicorniculus:
   (pl. corniculi) (also, external malae) a usually horn-like process (sometimes toothed, bifurcate, trifurcate, spine-like, spatulate, or membranous) on the subcapitulum of parasitiform mites that usually supports the salivary styli.  A toothed corniculus could be confused with a rutellum, a possibly homologous structure in Acariformes and Opilioacarida. Phytoseiid image is spatulate corniculus.
   of normal length, not reaching the anterior margin of the palppalp:
   (= pedipalp) the second pair of limbs in arachnids, used in feeding and originating on either side of the chelicerae.  In mites, the palps may be vestigial, with only a few segments, or have a maximum of  5 freely articulating segments (rarely the femur is subdivided) and a distal or subdistal apotele.
   femur; anterior margin of anterior dorsaldorsal:
   relating to the upper or back side; opposed to ventral.
   shield convex.............................. 4
   - Corniculicorniculus:
   (pl. corniculi) (also, external malae) a usually horn-like process (sometimes toothed, bifurcate, trifurcate, spine-like, spatulate, or membranous) on the subcapitulum of parasitiform mites that usually supports the salivary styli.  A toothed corniculus could be confused with a rutellum, a possibly homologous structure in Acariformes and Opilioacarida. Phytoseiid image is spatulate corniculus.
   elongate, extending beyond palppalp:
   (= pedipalp) the second pair of limbs in arachnids, used in feeding and originating on either side of the chelicerae.  In mites, the palps may be vestigial, with only a few segments, or have a maximum of  5 freely articulating segments (rarely the femur is subdivided) and a distal or subdistal apotele.
   femur-genugenu:
   (pl. genua) (= patella) the 4th leg segment, between the femur and tibia.
   articulation; margin of anterior dorsaldorsal:
   relating to the upper or back side; opposed to ventral.
   shield concave.............................. Cornigamasus

4. Genital shieldgenital shield:
   a shield or shields covering the genital opening; in female mongynaspine Mesostigmata this shield is usually called the epigynal (epigynial) shield.  
   (or genital region of hologastric shieldhologastric shield:
   in Mesostigmata, a shield that covers the genital, ventral and anal regions; a ventrianal shield that incorporates the metapodal elements and is fused to the epigynal shield. 
   ) subtriangularsubtriangular:
   more or less triangular.  
   , acuminate.............................. 5
   - Genital region of hologastric shieldhologastric shield:
   in Mesostigmata, a shield that covers the genital, ventral and anal regions; a ventrianal shield that incorporates the metapodal elements and is fused to the epigynal shield. 
   distally tricuspidtricuspid:
   having three points or cusps, e.g., the gnathotectum of some Mesostigmata.
   .............................. Porrhostaspis

5. Lateral seta of palppalp:
   (= pedipalp) the second pair of limbs in arachnids, used in feeding and originating on either side of the chelicerae.  In mites, the palps may be vestigial, with only a few segments, or have a maximum of  5 freely articulating segments (rarely the femur is subdivided) and a distal or subdistal apotele.
   femur (al) entireentire:
   a shield or sclerite with a continuous margin without incisions.
   , usually spatulatespatulate:
   (Latin spatula = spoon) spatula-shaped; variously interpreted, but usually referring to setae that are flattened and somewhat expanded distally.
   .............................. 8
   - Lateral seta of palppalp:
   (= pedipalp) the second pair of limbs in arachnids, used in feeding and originating on either side of the chelicerae.  In mites, the palps may be vestigial, with only a few segments, or have a maximum of  5 freely articulating segments (rarely the femur is subdivided) and a distal or subdistal apotele.
   femur bifid, serrateserrate:
   with closely set teeth that resemble the cutting edge of a saw.
   , or serrateserrate:
   with closely set teeth that resemble the cutting edge of a saw.
   -spatulate.............................. 6

6. Setae of dorsal hexagondorsal hexagon:
   a fancied hexagonal area staked out by setal pairs j5, z5 and j6 in the podonotal region of many mesostigmatans; useful for orienting to setae to determine designations (see Lindquist-Evans system);  setae j3-5 may also form a hexagonal array.
   dissimilar, seta z5 longer and usually thicker than j5 and j6............................... 7
   - Setae of dorsal hexagondorsal hexagon:
   a fancied hexagonal area staked out by setal pairs j5, z5 and j6 in the podonotal region of many mesostigmatans; useful for orienting to setae to determine designations (see Lindquist-Evans system);  setae j3-5 may also form a hexagonal array.
   similar in size and ornamentation.............................. Vulgarogamasus

7. Sternal shieldsternal shield:
   a shield in the anterior intercoxal region of parasitiform mites that bears one or more pairs of sternal setae.
   entire; seta z5 usually thicker than j5 and j6 and distally pilosepilose:
   with a covering of hairs or hair-like processes.
   associated with dung (and dung beetles), compost, etc.............................. Parasitus
   - Sternal shieldsternal shield:
   a shield in the anterior intercoxal region of parasitiform mites that bears one or more pairs of sternal setae.
   split medially; seta z5 usually longer than j5 and j6 but similar in form; associated with bark beetles.............................. Schizosthetus

8. Dorsaldorsal:
   relating to the upper or back side; opposed to ventral.
   shield completely divided.............................. 9
   - Schizodorsal shieldschizodorsal shield:
   in Mesostigmata, a holodorsal shield that incised laterally at about the midpoint or podonotal and opisthonotal shields that are fused only medially.
   .............................. Gamasodes bispinosus group

9. Seta z5 of dorsal hexagondorsal hexagon:
   a fancied hexagonal area staked out by setal pairs j5, z5 and j6 in the podonotal region of many mesostigmatans; useful for orienting to setae to determine designations (see Lindquist-Evans system);  setae j3-5 may also form a hexagonal array.
   thickened and distally pilosepilose:
   with a covering of hairs or hair-like processes.
   ; associated with various insects.............................. 10
   - Seta z5 simplesimple:
   unadorned; simple setae are needle-like and without hairs or pectins.
   ; associated with carrion beetles (Silphidae).............................. Poecilochirus

10. Articulationarticulation:
    a region of differentiated cuticle joining two parts of an exoskeleton; a joint, scissure or furrow.
    between sternal and metasternal shields oblique; ambulacra of legs II–IV simplesimple:
    unadorned; simple setae are needle-like and without hairs or pectins.
    , rounded.............................. Gamasodes
    - Articulationarticulation:
    a region of differentiated cuticle joining two parts of an exoskeleton; a joint, scissure or furrow.
    (or suturesuture:
    an inflexible juncture between two body parts; line of fusion between two formerly separate body parts or regions.  This term is often misused for flexible articulations.
    ) between sternal and metasternal shields transverse; ambulacra of legs II–IV long and acuminate.............................. Trachygamasus

Diagnosis

Female dorsaldorsal:
relating to the upper or back side; opposed to ventral.
shield with lateral incisions or completely divided, setaeseta:
(pl. setae, from L. = bristle) cuticular process composed of a hollow shaft (sometimes filled with a refractive material) produced from a membranous socket (the alveolus); the hair-like, spine-like, branched or variously expanded structures on the surfaces of the legs and body.  Most setae function as mechanoreceptors, but others (e.g., solenidia) are chemoreceptors or have unknown or ambiguous functions.
of dorsal hexagondorsal hexagon:
a fancied hexagonal area staked out by setal pairs j5, z5 and j6 in the podonotal region of many mesostigmatans; useful for orienting to setae to determine designations (see Lindquist-Evans system);  setae j3-5 may also form a hexagonal array.
dissimilar in form usually z5 larger and ornamented); dorsaldorsal:
relating to the upper or back side; opposed to ventral.
shield entireentire:
a shield or sclerite with a continuous margin without incisions.
in males and divided in deutonymphs. Peritrematalperitrematal:
(peritrematic) of or referring to the peritreme; adjectival form of peritreme.
shield fully fused to dorsaldorsal:
relating to the upper or back side; opposed to ventral.
shield. Female sternal shieldsternal shield:
a shield in the anterior intercoxal region of parasitiform mites that bears one or more pairs of sternal setae.
with three pairs of setaeseta:
(pl. setae, from L. = bristle) cuticular process composed of a hollow shaft (sometimes filled with a refractive material) produced from a membranous socket (the alveolus); the hair-like, spine-like, branched or variously expanded structures on the surfaces of the legs and body.  Most setae function as mechanoreceptors, but others (e.g., solenidia) are chemoreceptors or have unknown or ambiguous functions.
; genital shieldgenital shield:
a shield or shields covering the genital opening; in female mongynaspine Mesostigmata this shield is usually called the epigynal (epigynial) shield.  
sharply triangular, flanked by large metasternal shields, and abutting or fused to a ventrianal shieldventrianal shield:
in Mesostigmata, a ventral shield bearing the anal opening, circum anal setae, and one or more pairs of ventral setae or pores (lyrifissures) [see anal shield]; maybe rather narrow or very broad and covering most of the gaster.
that is variously fused with peritrematalperitrematal:
(peritrematic) of or referring to the peritreme; adjectival form of peritreme.
and other shields. Tibiatibia:
(pl. tibiae) the leg segment between the genu and the tarsus.
I typically with four ventral setaeseta:
(pl. setae, from L. = bristle) cuticular process composed of a hollow shaft (sometimes filled with a refractive material) produced from a membranous socket (the alveolus); the hair-like, spine-like, branched or variously expanded structures on the surfaces of the legs and body.  Most setae function as mechanoreceptors, but others (e.g., solenidia) are chemoreceptors or have unknown or ambiguous functions.
, six dorsal setaeseta:
(pl. setae, from L. = bristle) cuticular process composed of a hollow shaft (sometimes filled with a refractive material) produced from a membranous socket (the alveolus); the hair-like, spine-like, branched or variously expanded structures on the surfaces of the legs and body.  Most setae function as mechanoreceptors, but others (e.g., solenidia) are chemoreceptors or have unknown or ambiguous functions.
, and two al setaeseta:
(pl. setae, from L. = bristle) cuticular process composed of a hollow shaft (sometimes filled with a refractive material) produced from a membranous socket (the alveolus); the hair-like, spine-like, branched or variously expanded structures on the surfaces of the legs and body.  Most setae function as mechanoreceptors, but others (e.g., solenidia) are chemoreceptors or have unknown or ambiguous functions.
(2 3/2 3/2 2); tibiatibia:
(pl. tibiae) the leg segment between the genu and the tarsus.
III with eight or nine setaeseta:
(pl. setae, from L. = bristle) cuticular process composed of a hollow shaft (sometimes filled with a refractive material) produced from a membranous socket (the alveolus); the hair-like, spine-like, branched or variously expanded structures on the surfaces of the legs and body.  Most setae function as mechanoreceptors, but others (e.g., solenidia) are chemoreceptors or have unknown or ambiguous functions.
(2 1/1 2/1 1(2)); chaetotaxychaetotaxy:
the use of setal position and form in taxonomy; see Lindquist-Evans system, Grandjean system, Rostral-lamellar system, etc.
of genugenu:
(pl. genua) (= patella) the 4th leg segment, between the femur and tibia.
IV (2 2/1 3/1 1). Palptarsal apotelepalptarsal apotele:
(= palp apotele, palptarsal claw) the most distal segment of the palp; absent in Acariformes, claw-like in Opilioacarida, and a subdistal, tined structure in the Mesostigmata.
3-tined. Female often with an elaborate endogynium. Male with presternal genital aperturegenital aperture:
the genital opening or acetabulum.
on holoventral or sternitigenital shieldsternogenitalshield:
(also sternitogenital, sternitigenital) in male Mesostigmata, a shield covering the intercoxal region and bearing the genital opening.  
, and typically with highly developed spurs on legs II; chelicerae with sperm-holding structure (spermatotremespermatotreme:
a slit-like opening on the movable digit of male Parasitidae that grasps the neck of the spermatophore during sperm transfer; considered to be a foramen left by the distal fusion of a spermatodactyl to the movable digit.
) which is coalescedcoalesced:
united, grown together, as for example, the genital and anal regions of some prostigmatans.
distally with movable digit. Larva without pygidial shieldpygidial shield:
(pygidial sclerite) in Mesostigmata, a shield at the back end of the idiosoma.
; protonymphal pygidial shieldpygidial shield:
(pygidial sclerite) in Mesostigmata, a shield at the back end of the idiosoma.
reduced laterally, generally with 4–5 pairs of setaeseta:
(pl. setae, from L. = bristle) cuticular process composed of a hollow shaft (sometimes filled with a refractive material) produced from a membranous socket (the alveolus); the hair-like, spine-like, branched or variously expanded structures on the surfaces of the legs and body.  Most setae function as mechanoreceptors, but others (e.g., solenidia) are chemoreceptors or have unknown or ambiguous functions.
(without setaeseta:
(pl. setae, from L. = bristle) cuticular process composed of a hollow shaft (sometimes filled with a refractive material) produced from a membranous socket (the alveolus); the hair-like, spine-like, branched or variously expanded structures on the surfaces of the legs and body.  Most setae function as mechanoreceptors, but others (e.g., solenidia) are chemoreceptors or have unknown or ambiguous functions.
S4–S5), or shield sometimes absent; dorsaldorsal:
relating to the upper or back side; opposed to ventral.
shield of deutonymphdeutonymph:
(also deuteronymph) the second nymphal stage or instar.
divided, apicotarsusapicotarsus:
(= acrotarsus) distal subdivision of the tarsus, usually of tarsus I.
present in deutonymphs.

Similar taxa

Similar taxa in key. Female Pergamasinae have holodorsal shields with the dorsal hexagondorsal hexagon:
a fancied hexagonal area staked out by setal pairs j5, z5 and j6 in the podonotal region of many mesostigmatans; useful for orienting to setae to determine designations (see Lindquist-Evans system);  setae j3-5 may also form a hexagonal array.
setae similar in form (species of Vulgarogamasus of the subfamily Parasitinae also have similar dorsal hexagondorsal hexagon:
a fancied hexagonal area staked out by setal pairs j5, z5 and j6 in the podonotal region of many mesostigmatans; useful for orienting to setae to determine designations (see Lindquist-Evans system);  setae j3-5 may also form a hexagonal array.
setae). Veigaiidae may be superficially similar, but have anal shields, a scale-like process above the palp apotelepalptarsal apotele:
(= palp apotele, palptarsal claw) the most distal segment of the palp; absent in Acariformes, claw-like in Opilioacarida, and a subdistal, tined structure in the Mesostigmata.
, often moustache-likemoustache-like:
having the appearance of a well developed handlebar moustache, as in the internal malae of most species of Veigaia (Mesostigmata).  
internal malae, and a spermatodactylspermatodactyl:
(also spermadactyl) the 'sperm finger' on the chelicerae of male dermanyssine Mesostigmata used to transfer sperm to the secondary sperm system in the female; spermatodactyls take various forms, from simple finger-like processes to very long, contorted structures.  
that is free distally on the male chelicerae.

Similar taxa not in key. Most members of the suborder Trigynaspida have three shields around the genital opening, but retain setae av4 and pv4 on an intercalary scleritesclerite:
A component section of an exoskeleton; a plate forming the skeleton of an arthropod.
and excrescences on the movable digit.

Ecology and distribution

Predators of small arthropods and other invertebrates. Most species appear to be bisexual and diplodiploidy has been demonstrated in the group. Phoresyphoresy:
a type of migration where mites board larger animals (usually insects or other arthropods) and cease or otherwise alter normal behaviors (e.g., feeding, reproduction, movement) until some cue elicits the departure from the animal and the resumption of normal behavior.  Phoresy usually results in the dispersal of populations, but may result in reaggregation, especially for mites using highly specialized habitats (e.g., pitcher plants and other phytotelmata).  Some mites hold on to their phoretic carriers with specialized structures (e.g., the anal pedicel in Uropodina; modified legs I in phoretomorphic Pygmephoridae; a specialized tooth on the chelicerae of many Macrocheles), but others simply use their feet or grip a seta with unmodified mouthparts.  Phoretic relationships my be highly host specific, very general, or anywhere in between, depending on the species.  In earlier work, phoresy was differentiated from parasitism by whether or not feeding occurred on the host.  However, recent work has shown that some phoretic mites may also feed on or otherwise harm their host.
is not known in the Pergamasinae, but deutonymphs of Parasitinae are phoretic and are aggressive predators in patchy organic habitats such as dung, carrion, compost, rotting fungi, and beach wrack. Species of Schizothetus are associated with bark beetles in the genera Dendroctonus and Ips.

References

• Al-Amidi et al. 1991Al-Amidi et al. 1991:
  Al-Amidi AHK, Dunne R, Downes MJ. 1991. Parasitus bituberosus (Acari: Parasitidae): an agent for control of Lycoriella solani (Diptera: Sciaridae) in mushroom crops. Experimental and Applied Acarology 11: 159–166.
• Athias-Henriot 1980aAthias-Henriot 1980a:
  Athias-Henriot C. 1980a. Parasitidae nord-coréens (Parasitiformes): apparentés au genre Neogamasus Tikh., avec création de trois nouveaux genres. Annales Musei Historico-Naturalis Hungarici. 72: 285–294.
• Athias-Henriot 1982aAthias-Henriot 1982a:
  Athias-Henriot C. 1982a. Schizosthetus n.g. (type Eugamasus lyriformis McGr. & Farr., 1969) avec deux espèces nouvelles (Parasitiformes, Parasitidae). Acarologia 23: 207–214.
• Athias-Henriot 1982bAthias-Henriot 1982b:
  Athias-Henriot C. 1982b. Sur le genre monotypique Parasitus Latr. (Parasitiformes, Parasitidae). Diagnose, définition, distribution. Revue Suisse de Zoologie 89: 3–6.
• Axtell 1981Axtell 1981:
  Axtell RC. 1981. Use of predators and parasites in filth fly IPM programs in poultry housing. pp. 26-43. In: Patterson RS, Koehler PG, Morgan PB, and Harris RL, eds. Status of Biological Control of Filth Flies. Proceedings of a Workshop, Feb. 4-5, 1981, University of Florida, Gainesville. USDA Science and Education Administration.
• Beninger 1993Beninger 1993:
  Beninger CW. 1993. Egg predation by Poecilochirus carabi (Mesostigmata: Parasitidae) and its effect on reproduction of Nicrophorus vespilloides (Coleoptera: Silphidae). Environmental Entomology 22: 766–769.
• Bhattacharyya 1963Bhattacharyya 1963:
  Bhattacharyya SK. 1963. A revision of the British mites of the genus Pergamasus Berlese s.lat. (Acari: Mesostigmata). Bulletin of the British Museum (Natural History), Zoology 11 (2): 131–242 + 8 plates.
• Blackman and Evans 1994Blackman and Evans 1994:
  Blackman SW, Evans GO. 1994. Observations on a mite (Poecilochirus davydovae) predatory on the eggs of burying beetles (Nicrophorus vespilloides) with a review of its taxonomic status. Journal of Zoology 234: 217–227.
• Brown and Wilson 1994Brown and Wilson 1994:
  Brown JM, Wilson DS. 1994. Poecilochirus carabi: Behavioral and life-history adaptations to different hosts and the consequences of geographical shifts in host communities. pp. 1–22. In: Houck MA, ed. Mites: Ecological and evolutionary analyses of life-history patterns. Chapman & Hall, New York.
• Hennessey and Farrier 1989Hennessey and Farrier 1989:
  Hennessey MK, MH Farrier 1989. Mites of the family Parasitidae (Acari: Mesostigmata) inhabiting forest soils of North and South Carolina. NC Agricultural Research Service Technical Bulletin No. 291: 78 pp.
• Hyatt 1980Hyatt 1980:
  Hyatt KH. 1980. Mites of the subfamily Parasitinae (Mesostigmata: Parasitidae) in the British Isles. Bulletin of the British Museum (Natural History) Zoology 38: 237–378.
• Hyatt 1987Hyatt 1987:
  Hyatt KH. 1987. Mites of the genus Holoparasitus Oudemans, 1936 (Mesostigmata: Parasitidae) in the British Isles. Bulletin of the British Museum (Natural History) Zoology 52: 139–164.
• Juvara-Bals 2002Juvara-Bals 2002:
  Juvara-Bals I. 2002. A revision of the genus Heteroparasitus new status, with the description of Heteroparasitus (Medioparasitus) athiasae subgen. n., sp. n. from Spain and with a key to the genera of Pergamasinae (Acari, Gamasida, Parasitidae). Revue Suisse de Zoologie 109: 23–46.
• Krantz 1983Krantz 1983:
  Krantz GW. 1983. Mites as biological control agents of dung-breeding flies, with special reference to the Macrochelidae. pp. 91–98. In: Hoy MA, Cunningham GL, Knutson L, eds. Biological control of pests by mites. University of California Agriculture Experiment Station, Special Publication 3304, Berkley.
• Micherdzinski 1969Micherdzinski 1969:
  Micherdzinski W. 1969. Die Familie Parasitidae Oudemans 1901 (Acarina, Mesostigmata). Zakład Zoologii Systematycznej Polskiej Akademii Nauk, Krakow. 690 pp.
• Richards and Richards 1976Richards and Richards 1976:
  Richards LA, Richards KW. 1976. Parasitid mites associated with bumblebees in Alberta, Canada (Acarina: Parasitidae; Hymenoptera: Apidae). II. Biology. University of Kansas Science Bulletin 51: 1–18.
• Schousboe 1987Schousboe 1987:
  Schousboe C. 1987. Deutonymphs of Parasitellus phoretic on Danish bumblebees (Parasitidae, Mesostigmata; Apidae, Hymenoptera). Acarologia 28: 37–41.
• Schwarz and Müller 1992Schwarz and Müller 1992:
  Schwarz HH, Müller JK. 1992. The dispersal behaviour of the phoretic mite Poecilochirus carabi (Mesostigmata, Parasitidae): Adaptation to the breeding biology of its carrier Necrophorus vespilloides (Coleoptera, Silphidae). Oecologia 89: 487–493.
• Springett 1968Springett 1968:
  Springett BP. 1968. Aspects of the relationship between burying beetles, Necrophorus spp. and the mite, Poecilochirus necrophori Vitz. Journal of Animal Ecology 37: 417–424.
• Wrensch and Johnston 1983Wrensch and Johnston 1983:
  Wrensch DL, Johnston DE. 1983. Sexual dimorphism in deutonymphs of mites of the family Parasitidae (Acari: Mesostigmata). Annals of the Entomological Society of America 76: 473–474.