Trigynaspida

Superorder Parasitiformes

Order Mesostigmata

Suborder Trigynaspida

Cohorts (Superfamilies): Cercomegistina (Cercomegistoidea), Antennophorina (Antennophoroidea, Celaenopsoidea, Fedrizzioidea, Megisthanoidea, Parantennuloidea, Aenictequoidea)

 

Common names: trigynaspids, cercomegistines, antennophorines

 

Probability of Encounter: low to medium

 

Quarantine importance: Most are rare and have unknown ecologies; however, many trigynaspids are associated with insects, including species parasitic on ants, and a few are associated with snakes and lizards.  None are known to be pests of crops or parasites of livestock or domestic animals.

 

Diagnosis.   Mesostigmata with the adult female genital region  having 2-4 shields or their remnants: mesogynial shield often reduced, without setae, latigynial shields often well developed (1- several pairs of setae); pregenital shield (sternogynium) free, fused to sternal elements, or absent (with 0-1 pair of setae).  Tarsus IV with intercalary sclerite bearing setae av4/pv4.  

 

Body often with moderate hypertrichy and separate podonotal and opisthonotal shields or holodorsal shield, rarely with opisthonotal region with separate mesonotal and pygidial elements.  Venter usually with large ventrianal or genitoventral shield, rarely with small anal shield; sternal shield well developed to fragmented.  Tarsus I with or without claws.  Unpaired, postanal seta usually present in larva, but absent in adult.  Chelicerae chelate-dentate to edentate; movable digit with 1-3 brush-like, mop-like or dendritic excrescences; palp genu with 5-7 setae.  Male genital opening intercoxal or at base of tritosternum; spermatodactyl absent.

 

Similar mitees.  Parasitina (Mesostigmata) have enlarged metasternal shields that superficially resemble the trigynaspid condition, and some primitive Uropodina (e.g. Trachytes)  do retain separate latigynial shields.  However, neither of these taxa retain av4/pv4 on tarsus IV, and uropodines usually have hidden capitula and elongate chelicerae.

 

Ecology & Distribution.  Cercomegistina are mostly free-living predators found in forest soil, decaying logs, or in beetle galleries under bark.  Antennophorina are mostly insect associates as adults (usually paraphages of beetles [e.g. Passalidae, Carabidae] and millipedes) and free-living predators in decaying logs,  insect galleries or nests as immatures.  However, species in at least 3 families are associated with lizards or snakes and appear to be parasites.

 

References

Butler L, Hunter PE.  1968.  Redescription of Megisthanus floridanus with observations on its biology (Acarina: Megisthanidae).  The Florida Entomologist 51: 187-197.

Camin JH & Gorirossi FE.  1955.  A revision of the suborder Mesostigmata (Acarina), based on new interpretations of comparative morphological data.  Chicago Academy of Sciences Special Publication 11: 1-70.

Franks NR, Healy KJ, and Byrom L.  1991.  Studies on the relationship between the ant ectoparasite Antennophorus grandis (Acarina: Antennophoridae) and its host Lasius flavus (Hymenoptera: Formicidae).  J. Zool. Lond. 225: 59-70.

Johnston, D.E.  1982.  Mesostigmata.  In: Parker, S.P. (ed.)  Synopsis and classification of living organisms.  McGraw-Hill, New York, p. 112-116.

Kethley, J. B. 1977. A review of the higher categories of Trigynaspida (Acari: Parasitiformes). International Journal of Acarology 3: 129-149.

Kinn DN.  1971.  The life cycle and behaviour of Cercoleipus coelonotus (Acarina: Mesotigmata) including a survey of phoretic mite associates of California Scolytidae.  Univ. Calif. Publ. Entomol. 65: 66 pp.

Krantz GW.  1978.  A Manual of Acarology.  OSU Bookstores: Corvallis.

Krantz, GW & Ainscough, B.  1990.  Mesostigmata.  pp. 583-665, in DL Dindal (ed) Soil Biology Guide.  John Wiley & Sons: Brisbane.

Lindquist, E. E. and Moraza, M. L. 1993. Pyrosejidae, a new family of trigynaspid mites (Acari: Mesostigmata: Cercomegistina) from Middle America. Acarologia 39: 203-226.

Seeman OD & Walter DE.  1997.  A new species of Triplogyniidae (Mesostigmata: Celaenopsoidea) from Australian rainforests.  International Journal of Acarology 23: 49-59.

Walter, D.E.  2000.  A jumping mesostigmatan: Saltiseius hunteri, n.g., n. sp. (Acari: Mesostigmata: Trigynaspida: Saltiseiidae, n. fam.).  International Journal of Acarology 26: 25-31.