- Selection of uropodine mites – center and lower right are ant associates
I just noticed an error in my posting on ‘A mite with a mite problem’ – the lizard was covered with deutonymphs of a uropodid mite, not of an astigmatan (see Domrow, R. 1981. A small lizard stifled by phoretic deutonymphal mites (Uropodina). Acarologia 22:247–52). However, that gives me an excuse to post on the Uropodina, a fascinating, if poorly studied group.
Early derivative uropodines have a variety of plates and often a thick covering of highly ornamented cerotegument (e.g. the long mite with the tail in the plate and the mite in the viewer’s upper righthand corner). The more derived lineages, however, use shiny armour for defence and sometimes add detritus to the mix, e.g. the yellow Basket Mites (probably species of Clausiadinychus) in the lower left (ventral view) and upper right region (lateral view). These mites have a basket formed of raised setae into which they deposit little balls of detritus. Most higher uropodines, however, look more like turtles than baskets, and are sometimes called Tortoise Mites (not to be confused with the mites that are parasitic on tortoises or other turtles).
The Uropodina is a massive radiation of mesostigmatans (Acari: Parasitiformes: Mesostigmata) that is most diverse in species and ecological associations in the southern lands that once composed Gondwana. The elf hat mite is one that I have already posted on. Mostly what these mites do is a mystery. For example, I commonly get sent samples of Uroactinia agitans (probably better known as Fuscouropoda agitans) from people with earthworm colonies where these mites can build up tremendous populations. As far as I know, these mites do no direct damage to the worms, although they may feed on dead or dying worms and possibly compete for resources. But that is as far as I know – and a search on BIOSIS this morning failed to find any recent studies that support this relatively benign interpretation (the paper I read was from 1953). So, if a no one is sure what a common synanthrope does, what we know about most Gondwanan species is probably minimal.
One partial exception are the uropodine mites associated with doryline and ecitonine army ants in the Neotropics. The diversity and extent of these associations was first documented by the late Carl Rettenmeyer (see Myrmecos Blog for a thoughtful review of his influence on ant people) during his PhD studies. Since then, Richard Elzinga (see list of papers below) has described many of these fascinating myrmecophiles (under a variety of family and generic names now mostly treated as subgenera of Trichocylliba). Unlike most higher uropodines, these mites attach to the ants as adults, rather than deutonymphs. Some just hold on tightly with well developed claws to the mandibles, head or body of the ant. Others, though, have bizarre modifications to facilitate attachment to specific spots on their ant hosts. Some have toothed lobes of the body that clasp an ant leg segment or have the entire body modified to fit a leg or antennal segment. Elongate mites of one genus (Habeogula) clamp the ant’s neck and align themselves under the labial region of the host’s head, presumably to steal food.
This is just a taste of the mesostigmatan associates of ants which include groups outside the Uropodina and such strange forms as the Larvamimidae, which look like army ant larvae and are treated as such by the ants, including lugging them around (Elzinga 1993). Other mites are known to be kleptoparasites, e.g. Antennophorus grandis on the ant Lasius flavus (Franks et al. 1991). True ectoparasitism has been demonstrated for one uropodine mite, Macrodinychus sellnicki (Dinychidae), which slowly suck the pupae of the Neotropical ant, Paratrechina fulva into shriveled little husks (Krantz et al. 2007). A partial list of references follows.
Elzinga, R. J. 1978. Holdfast mechanisms in certain uropodine mites (Acarina: Uropodina). Ann. Entomol. Soc. Amer. 71: 896–900.
Elzinga, R. J. 1982. The generic status and six new species of Trichocylliba (Acari: Uropodina). Acarologia 23:3–18.
Elzinga, R. J.1982. The genus Antennequesoma (Acari: Uropodina) and descriptions of four new species. Acarologia 23:319–25.
Elzinga, R. J. 1982. Th e genus Coxequesoma (Acari: Uropodina) and descriptions of four new species. Acarologia 23:215–24.
Elzinga, R. J. 1989. Habeogula cauda (Acari: Uropodina), new genus and species of mite from the army ant Labidus praedator (F. Smith). Acarologia 30:341–44.
Elzinga, R. J. 1991. Two new elongate species of Planodiscus (Acari: Uropodina) with a key to the known species. Acarologia 32:109–14.
Elzinga, R. J. 1993. Larvamimidae, a new family of mites (Acari: Dermanyssoidea) associated with army ants. Acarologia 34:95–103.
Elzinga, R. J. & C. W. Rettenmeyer. 1970. Five new species of Planodiscus (Acarina: Uropodina). Acarologia 12:59–70.
Elzinga, R. J. 1974. Seven new species of Circocylliba (Acarina: Uropodina). Acarologia 16:595–611.
Franks, N. R., K. J. Healy, & L. Byrom. 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.
Gotwald, W.H. Jr. 1996. Mites That Live with Army Ants: A Natural History of Some Myrmecophilous Hitch-Hikers, Browsers, and Parasites. Journal of the Kansas Entomological Society, Vol. 69, No. 4, Supplement: Special Publication Number 2: Proceedings of the Eickwort Memorial Symposium (Oct., 1996), pp. 232-237.
Krantz, G. W., L. A. Gomez, and V. E. Gonzalez. 2007. Parasitism in the Uropodina: A case history from Colombia. In Morales-Malacara et al., 29–38. Acarology XI, Proceedings, XI International Congress of Acarology. Mérida, Universidad Nacional Autónoma de México.
Rettenmeyer, C. W. 1961. Arthropods associated with Neotropical army ants with a review of the behavior of these mites (Arthropoda: Formicidae: Dorylinae). Ph.D. diss., Univ. Kansas.
Rettenmeyer, C. W. 1962. Notes on host specifi city and behavior of mymecophilous macrochelid mites. J. Kans. Entomol. Soc. 35:358–60.