Phoresy and Mites: More Than Just a Free Ride.

Mites are masters at attaching to larger animals, often insects, in a temporary symbiosis called phoresy that allows these tiny animals to exploit patchy resources. In this article, we examine phoresy in the Acari, including those that feed on their carriers in transit, from a broad perspective. From a phylogenetic perspective, phoresy has evolved several times from free-living ancestors but also has been lost frequently. Rotting logs appear to be the first patchy resource exploited by phoretic mites, but the evolution of rapid life cycles later permitted exploitation of short-lived resources. As phoresy is a temporary symbiosis, most species have off-host interactions with their carrier. These relationships can be highly complex and context dependent but often are exploitative of the carrier's resources or progeny. Transitions from phoresy to parasitism seem widespread, but evidence for transitions from obligate phoretic parasitism to permanent parasitism is weak.

A revision of the Heatherellidae (Parasitiformes: Mesostigmata) with a new genus and two new species from Australasia.

The discovery of a new genus of Heatherellidae in New Zealand has led us to revise this enigmatic family and its constituent genera. Aheatherella n. gen., based on A. mira n. sp. from the North Island of New Zealand, lacks some of the derived character states that link the Australian Heatherella, most notably the lack of sexual dimorphism in the dorsal shields and in the presence of peritremes in adult Aheatherella. Heatherella osleri n. sp. is described from New South Wales, extending the distribution of this genus beyond Queensland. New collection records of H. callimaulos and a key to the genera and species of the family are provided. We propose that the Heatherellidae-previously placed in its own cohort outside the Gamasina-are best considered a superfamily of gamasine mites within the subcohort Epicriiae.

The Importance of Habitat in the Ecology of Decomposition on Rabbit Carcasses in Malaysia: Implications in Forensic Entomology.

The stages of decomposition and the faunal succession on rabbit carcasses in three different habitats, namely jungle, rural, and highland areas, were studied. Three New Zealand White rabbit (Oryctolagus cuniculus) carcasses weighing ∼2 kg were sampled daily until the decomposition process was completed. Representative specimens of adult flies, larvae, pupa, and mites were collected from the carcasses and processed in the laboratory. There were differences in decomposition rate and faunal succession between the carcasses. The fastest rate of decomposition was recorded in rural area, and the slowest rate of decomposition was recorded in highland area. The carcasses exhibited the same pattern of colonization by adult flies, but the dominant species of larvae and adult flies on each carcass in specific habitats were different. The primary species of flies recorded in jungle were Chrysomya megacephala F., Chrysomya rufifacies (Macquart), Chrysomya chani Kurahashi, Chrysomya villenuevi Patton, Chrysomya nigripes Aubertin, Chrysomya pinguis (Walker), Hemipyrellia ligurriens (Wiedemann), Hemipyrellia tagaliana (Bigot), Hypopyiopsis fumipennis (Walker), Hypopygiopsis violacea (Macquart), and Hydrotaea spinigera Stein represented by both adults and larvae. Musca domestica L., Atherigona sp., Lioproctia pattoni (Senior-White), Lioproctia saprianovae Pape & Bänziger, and Seniorwhitea princeps (Wiedemann) were represented by adults only. The biodiversity of flies in the rural area were C. megacephala, C. rufifacies, H. ligurriens, Fannia canicularis L., Hydrotaea chalcogaster (Wiedemann), and Hyd. spinigera represented by both adults and larvae, meanwhile M. domestica, Atherigona sp., Boettcherisca peregrina (Robineau-Desvoidy), Parasarcophaga taenionota Wiedemann, Parasarcophaga scopariiformis Senior-White, and S. princeps were represented by adults only. The species of flies collected in the highland area were Lucilia porphyrina (Walker), C. megacephala, C. rufifacies, C. villenuevi, C. pinguis, H. ligurriens, Hyd. spinigera, Hyd. chalcogaster, F. canicularis, and Boettcherisca highlandica Kurahashi & Tan represented by both adults and larvae, whereas C. nigripes, Chrysomya thanomthini Kurahashi & Tumrasvin, M. domestica, Atherigona sp., Parasarcophaga albiceps Meigen, P. taenionota, Sepsidae, Phoridae, and Millichidae were represented by adults only. Faunal succession followed the sequence of dominant flies, i.e., Calliphoridae, Sarcophagidae, Muscidae, Sepsidae, and lastly Stratiomyidae for jungle, or Sepsidae for rural and highland studies. Mites, from suborders Mesostigmata, Prostigmata, Astigmatina, and Oribatida, were also recovered throughout decomposition, which could be used for future implementation in forensic investigations. The data obtained from this study could provide more accurate indicators for local forensic scientists in solving criminal cases especially on the determination of time and primary location of death.

A review of the ecology and distribution of Protoribates (Oribatida, Oripodoidea, Haplozetidae) in Alberta, Canada, with the description of a new species.

The oribatid mite genus Protoribates Berlese (Haplozetidae) is reviewed for North America and the genus diagnosis is revised to account for the North American species, Protoribates robustior (Jacot, 1937) is redescribed and newly reported from western North America and a new species from Alberta is described. Protoribates haughlandae sp. n. is bisexual, heterotridactylous, and lives primarily in the peat soils of fens and bogs. Protoribates robustior is all-female, monodactylous, and occurs primarily in dry forests or in dry, treeless sites dominated by grasses, sedges, and shrubs. Both species feed on fungal hyphae and spores, but P. haughlandae also is an opportunistic predator and/or necrophage of small arthropods and P. robustior gut contents often include material that resembles plant cell walls. Examination of type specimens confirms that Protoribates prionotus (Woolley, 1968) is a junior synonym of the widespread Protoribates lophotrichus (Berlese, 1904). A key to differentiate Lagenobates from Protoribates and to identify the 7 species of the latter that are known or reported from North America is provided.

A new genus and family of sejine mites (Acari, Parasitiformes, Mesostigmata, Sejoidea) based on new species from Lord Howe Island and Brazil, and a redescription of Sejus americanus (Banks, 1902).

The Sejoidea currently contains three families (Sejidae, Ichthyostomatogasteridae, Uropodellidae) of enigmatic mesostigmatic mites with a mixture of characters of general distribution in the Parasitiformes (e.g., hypertrichy, tarsus IV with an intercalary sclerite bearing a pair of ventral setae, archispermous mating system) and derived character states both unique (e.g., distinctive female sterno-gential region; first hypostomal setae adjacent and more or less membranous) and apparently convergent with other Mesostigmata (e.g., 2-tined palpal apotele, reduced dorsal sclerotisation in the adult, phoretic deutonymph). In this paper, I review the characters defining the Sejoidea; propose a new genus, Reginacharlottia gen. nov. based on two new species: one from Lord Howe Island, New South Wales, Australia (R. lordhowensis sp. nov.) and one from Bahia State, Brazil (R. braziliensis sp. nov.) and erect a new family, Reginacharlottiidae fam. nov. to accommodate them. These new species share a number of unusual characters not otherwise known in the Sejida, including a plumose interdigital cheliceral excrescence, a highly reduced female genital shield, and a highly modified anal region covered by a pair of hypertrophied preanal setae; the postanal seta is absent. Adult female R. lordhowensis carry up to a dozen eggs that enclose fully developed larvae; the larvae also lack the postanal seta, but have a unique pygidial tubercle that may act as an egg burster. In addition, the female of Sejus americanus (Banks, 1902) is redescribed and the male described for the first time. Sejus species tend to be more typical of the warmer parts of the world, but S. americanus extends well into the boreal forest of Alberta, Canada (56 degrees N). A key to separate the families of Sejoidea is provided.

Keys and the crisis in taxonomy: extinction or reinvention?

Dichotomous keys that follow a single pathway of character state choices to an end point have been the primary tools for the identification of unknown organisms for more than two centuries. However, a revolution in computer diagnostics is now under way that may result in the replacement of traditional keys by matrix-based computer interactive keys that have many paths to a correct identification and make extensive use of hypertext to link to images, glossaries, and other support material. Progress is also being made on replacing keys entirely by optical matching of specimens to digital databases and DNA sequences. These new tools may go some way toward alleviating the taxonomic impediment to biodiversity studies and other ecological and evolutionary research, especially with better coordination between those who produce keys and those who use them and by integrating interactive keys into larger biological Web sites.

Kleptoparasites or commensals? Effects of Argyrodes antipodianus (Araneae: Theridiidae) on Nephila plumipes (Araneae: Tetragnathidae).

Argyrodes antipodianus is a small kleptobiotic spider that steals prey from webs of the large orb-weaving spider Nephila plumipes, and sometimes removes the web itself. We used experiments in a greenhouse to test how the presence of the kleptobiont, differences in food availability, and web damage affected fitness of the web owner. After 49 days, N. plumipes with four A. antipodianus on their webs gained 55% less weight and relocated their webs 4.5 times as often as spiders with no kleptobionts. Increased web relocation and decreased weight gain may have resulted from reduced prey levels or from web damage by A. antipodianus. A second experiment demonstrated that hosts gained weight at the feeding rate used in the first experiment, but not at lower rates. Web relocation rate also varied with feeding rate, but in a non-linear manner. Web loss was evaluated in a separate experiment, by manually removing one-quarter of the web every 5 days for 30 days; however, neither weight gain nor rate of web relocation were affected. We conclude that A. antipodianus is a true kleptoparasite that can reduce the growth rate of its host N. plumipes, but that neither food theft nor web damage alone explain increased web relocation rates.