Tydeoidea

Triophtydeus sp., copyright Pierre Bornand.

Belongs within: Prostigmata.
Contains: Procurvata, Tydeinae.

The Tydeoidea are a diverse group of free-living mites, many of which are notably resistant to desiccation. They may be more or less omnivorous in diet, with some species having been recorded feeding on a variety of animal, plant or fungal foods (Walter et al. 2009). Within the Tydeoidea, the Triophtydeidae are characterised by antenniform first legs, reduced or absent apoteles, and a median eyespot of subcuticular silver granules (Walter et al. 2009). Members of the subfamily Edbakerellinae bear solenidia on both the tibiae and tarsi of legs I and II whereas Triophtydeinae bear tarsal solenidia only. The Tydeidae are characterised by a loss of eugenital setae in females and a reduction of the cis-acetabulal area between the genital discs. However, monophyly of this group relative to the families Iolinidae and Ereynetidae (together forming the clade Procurvata) has been questioned because of the uncertain position of the distinctive species Australotydeus kirstenae (André & Fain 2000).

Characters (from Walter et al. 2009): Soft-bodied or ornamentally sclerotised dorsally. Gnathosoma with postcheliceral stigmata and tracheae distinct or obscure; cheliceral based fused or closely contiguous along their mesal edges, lacking dorsal cheliceral setae; fixed cheliceral digit reduced, lobe-like, movable cheliceral digit stylet-like or needle-like, rarely elongated, whip-like; subcapitulum characteristically with inversely T-shaped, sclerotised delineation of medial walls of lateral lips; palpi simple, with one to four (rarely five) segments. Prodorsum lacking anteromedian naso, with four pairs (sometimes as few as one pair) of setae, including one pair of bothridial sensilla; eyes present, with either surface cornea or subdermal pigmented areas, or absent. Opisthosoma with seven to eleven pairs of setae dorsally, laterally, and caudally, lacking postlarval setal additions or hypertrichy dorsally, but including a second pair of bothridial sensilla on posterodorsal aspect in certain Ereynetidae and Tydeidae; cupules (lyrifissures) present, sometimes obscure or absent; elements of opisthosomatic segments PS and AD present, including ps1 and, rarely, ps2 or ad1. Adult genital aperture positioned behind legs III and IV, usually longitudinal but transverse in some Iolinidae, and usually with two pairs of genital papillae (reduced to one pair or absent in Iolinidae). Males usually lacking an aedeagus (present in some Iolinidae). Leg setation lacking bothridial setae; tarsus I with one or two usually erect solenidia (with one recumbent solenidion in a rhagidial-like depression in some Ereynetidae) and with or without claws, occasionally with only a median empodium; tarsi II to IV generally with paired claws and a padlike setulose, but not rayed, median empodium. Generally with five active postembryonic instars: larva, protonymph, deutonymph, tritonymph, and adult (tritonymph sometimes suppressed).

<==Tydeoidea
    |--Triophtydeidae [Edbakerellidae, Meyerellidae] AF00
    |    |--Edbakerellinae [Meyerellinae] WL09
    |    |    |--Pseudotriophtydeus AF00
    |    |    `--Edbakerella André 2004 [=Meyerella Baker 1968 non Gray 1872] WL09
    |    |         `--‘Meyerella’ marshalli AF00
    |    `--Triophtydeinae AF00
    |         |--Pretriophtydeus tilbrooki AF00
    |         `--Triophtydeus Thor 1932 H98
    |              |--T. bakeri WL09
    |              |--T. immanis WL09
    |              |--T. lebruni H96
    |              `--T. pinicolus (Oudemans 1929) [=Tydeus pinicolus] H98
    `--Tydeidae [Tydidae] AF00
         |  i. s.: Paralorryia Baker 1965 A05
         |           `--P. eharai Baker 1968 C-RSV-S88
         |         Tectotydeus Oudemans 1937 A05
         |           `--*T. demeyeri (Oudemans 1929) [=Tydeus demeyeri] A05
         |         Brachytydeus Thor 1931 [incl. Raphitydeus Thor 1933] A05
         |           `--*B. cruciatus (Koch 1838) [=Tydeus cruciatus, Lorryia cruciata] A05
         |         Stylotydeus Thor 1933 A05
         |         Lasiotydaeus Berlese 1908 A05
         |         Eotydeus A05
         |         Melissotydeus macrosolenus André 1985 A05
         |         Venilia liberta WL09
         |         Metalorryia palpsetosa N07
         |         Retetydeus G38a
         |           |--R. catenulatus G38b
         |           `--R. viviparus Thor 1931 G38a
         |--Australotydeus [Australotydeinae] AF00
         |    `--A. kirsteneae Spain 1969 SL71
         `--+--Procurvata AF00
            `--+--Pretydeinae AF00
               |    |--Prelorryia indoniensis AF00, A05
               |    `--Pretydeus panitae A05
               `--Tydeinae AF00

*Type species of generic name indicated

REFERENCES

[A05] André, H. M. 2005. In search of the true Tydeus (Acari, Tydeidae). Journal of Natural History 39 (13): 975–1001.

[AF00] André, H. M., & A. Fain. 2000. Phylogeny, ontogeny and adaptive radiation in the superfamily Tydeoidea (Acari: Actinedida), with a reappraisal of morphological characters. Zoological Journal of the Linnean Society 130: 405–448.

[C-RSV-S88] Corpuz-Raros, L. A., G. C. Sabio & M. Velasco-Soriano. 1988. Mites associated with stored products, poultry houses and house dust in the Philippines. Philippine Entomologist 7 (3): 311–321.

[G38a] Grandjean, F. 1938a. Retetydeus et les stigmates mandibulaires des acariens prostigmatiques. Bulletin du Muséum National d’Histoire Naturelle, 2^e Série 10 (3): 279–286.

[G38b] Grandjean, F. 1938b. Au sujet de la néotenie chez les acariens. Comptes Rendus des Séances de l'Académie des Sciences 207: 1347–1350.

[H98] Halliday, R. B. 1998. Mites of Australia: A checklist and bibliography. CSIRO Publishing: Collingwood.

[H96] Hossain, S. M. 1996. Composition and fluctuations of some mite populations in apple orchards in western Norway. In: Mitchell, R., D. J. Horn, G. R. Needham & W. C. Welbourn (eds) Acarology IX vol. 1. Proceedings pp. 243–251. Ohio Biological Survey: Columbus (Ohio).

[N07] Niemczyk, E. 2007. Species, occurrence and role of tydeid mites (Acari: Tydeidae) in apple orchards. In: Morales-Malacara, J. B., V. M. Behan-Pelletier, E. Ueckermann, T. M. Pérez, E. G. Estrada-Venegas & M. Badii (eds) Acarology XI: Proceedings of the International Congress pp. 365–372. Instituto de Biología and Faculdad de Ciencias, Universidad Nacional Autónoma de México, Sociedad Latinoamericana de Acarología: México.

[SL71] Spain, A. V., & M. Luxton. 1971. Catalog and bibliography of the Acari of the New Zealand subregion. Pacific Insects Monograph 25: 179–226.

[WL09] Walter, D. E., E. E. Lindquist, I. M. Smith, D. R. Cook & G. W. Krantz. 2009. Order Trombidiformes. In: Krantz, G. W., & D. E. Walter (eds) A Manual of Acarology 3^rd ed. pp. 233–420. Texas Tech University Press.

Last updated: 19 July 2022.