Gerald W. Krantz

Identification of glandular and poroidal idionotal systems inMacrocheles perglaber F. & P. (Acari: Macrochelidae)

Based on a silver nitrate reduction treatment of adult and immatureMacrocheles perglaber, certain of the dorsal cuticular openings were found to be sites of glandular secretion and were designated as crobylophores. Reactivity tests showed an ontogenetic progression of dorsal gland activity, with those of tested larvae being non-reactive at all pore sites. Six pairs of glands were identified on the adult dorsum on the basis of reduction reactions.

Two new glaber group species of Macrocheles (Acari: Macrochelidae) from Southern Africa

Abstract Adult and immature stases of Macrocheles eurygaster and M. peregrinus n. spp. are described, and theglaber species group of Macrocheles is redefined. The potential importance of M. eurygaster and M. peregrinus as biological control agents of fly pests in Australia is noted.

Observations on pollen processing byPneumolaelaps longanalis (Acari: Laelapidae), a mite associate of bumblebees

Pneumolaelaps longanalis feeds on nectar and surface compounds of bumblebee-collected pollen grains by dissolving these materials in salivary secretions applied to the grain as it is manipulated by the mites mouthparts. Observations suggest that sugars applied to the pollen grain during bee-processing serve as a feeding stimulus for the mite.

A Unique Mesozoic Parasitic Association

State University 1993 13. Britton, E.B. In: The insects of Australia, p. 613. Melbourne: Melbourne University Press 1979 14. Wink, M.: Z. Naturforsch.50c, 868 (1995) 15. Käss, E., Wink, M.: Botanica Acta108, 149 (1995) 16. Wink, M., von Nickisch-Rosenegk, E.: J. Chem. Ecol. 23, 1549 (1997) 17. Kuschel, G., Oberprieler, R.G., Rayner, R.J.: Entomologica Scandinavica25, 137 (1994) 18. Marshall, G.A.K.: Rhynchophora: Curculionidae, p. 28. The Fauna of British India, including Ceylon and Burma. London: Taylor and Francis 1916 19. Dieckmann, L.: Entomologische Nachrichten. Berlin33, 97 (1989)

Mites, nematodes and the multimillion dollar weevil.

The African oil palm (Elaeis guineensis Jacquin) is a major plantation crop throughout much of the Old and NewWorld tropics, and its successful pollination is dependent primarily on the flower weevil, Elaeidobius kamerunicus (Faust). Among the several invertebrates found with E. kamerunicus in oil palm flowers are a bacteriophagous nematode and an undescribed mite species of the ascid genus Proctolaelaps. Both utilize E. kamerunicus for dispersal from senescent to newly opened oil palm inflorescences, and Proctolaelaps sp. feeds on the phoretic nematodes during the transfer phase.

A review of glaber-like species with reduced sclerotization and ventral ornamentation: The scutatus subgroup (Acari: macrochelidae: Macrocheles)

ABSTRACT Nine described and two new species of Macrocheles are united by a set of characters that are interpreted as reductions from a more strongly ornamented ancestor in the glaber species group (sensu Walter & Krantz 1986). These species most strongly resemble M. scutatus (Berlese), the smallest and least sclerotized species in Filipponi & Pegazzanos (1962) glaber-group, and herein are assigned to four species complexes in the scutatus subgroup. Species in the scutatus complex are distributed throughout the Old World, while those of the transmigrans, paganus, and rhodesi complexes are known only from subsaharan Africa and southeastern Asia. M. scutatus, a synanthropic species, is widely distributed (Europe, Africa, Asia, New Zealand) and uses the broadest range of phoronts of any species in the subgroup. Species in the remaining complexes usually are associated with scarab beetles of the tribe Scarabaeini, the dung rollers. Scutatus subgroup associates of Scarabaeini tend to have greatly reduced scler...

A remarkable example of predation in the parasitic mite family Macronyssidae

Abstract An undescribed genus and species of Macronyssidae has been found in guano of the bat Eptesicus fuscus in Indiana, USA, and in guano of an unidentified bat in Brazil. Unlike all other macronyssids, the new mite is predaceous on other mites in the guano and has no direct feeding relationship with the bat. We believe this is the first known instance, in any animal group, of reversion from parasitism to predation in all feeding stases.

Observations on the biology and behavior of Macrocheles mycotrupetes Krantz and Mellott (Acari: Macrochelidae)

Abstract The life history and behavior of Macrocheles mycotrupetes were examined in the laboratory. Unmated females failed to produce progeny, suggesting a mode of reproduction unlike that heretofore observed in other phoretic Macrocheles species. A discussion is presented on possible means of intergallery transfer by M. mycotrupetes based on its behavior in sand substrates and on seasonal activity of Mycotrupes gaigei and Geotrupes egeriei, its primary and secondary beetle phoronts. Laboratory observations suggest that lateral transfer of M. mycotrupetes occurs between subsurface beetle galleries, and verifies that mite movement through the sand substrate is triggered and guided by a beetle-generated kairomonal stimulus.

New records of mites (Arachnida: Acari) from Sable Island, Nova Scotia, Canada

The first investigations of the mite fauna of Sable Island, Nova Scotia, Canada, are reported. Fourteen species have been found. Uropoda orbicularis. (Muller) (Uropodidae) and Scarabaspis inexpectatus. (Oudemans) (Eviphididae) are newly recorded for North America, Macrocheles nemerdarius. Krantz and Whitaker (Macrochelidae) is newly recorded for Canada, and Trichoribates striatus. Hammer (Ceratozetidae) is recorded for the first time south of the subarctic zone. Colonization, dispersal, and the zoogeographic origins of the fauna are discussed in the context of the biological, geological, and human history of the island.

First ultrastructural observations on a putative sperm access system in veigaiid females (Veigaiidae, Gamasida)

Females of Dermanyssina display a reproductive system composed of a region involved in egg production and laying and another involved in sperm reception and likely storage. This second region is called the sperm access system, and it is related to a peculiar sperm transfer mode known as podospermy. Males have the chelicerae modified as gonopods which possess a peculiar process on the movable digit, the so-called spermatodactyl, which is used for sperm transfer. In Veigaiidae, males are rarely, exceptionally, or never found, and some species are considered to reproduce parthenogenetically. Known veigaiid males have spermatodactyls, sometimes of extraordinary length. The conspecific females have so-called spiral organs located behind coxae IV. It is likely that these organs, not known from other gamasid mites, represent the veigaiid sperm access system. In the present study, first ultrastructural details on these peculiar organs are given comparing a bisexual species (Veigaia sp.) with two species in which males are extremely rare (V. nemorensis and V. cerva). Each of these structures is composed of a major tube starting from the opening, a vesicle-like region, and several minor tubes. In general it is considered to be derived from an entapophysis. Muscles attach to the minor tube region. A general similarity to the phytoseiid type of sperm access systems may be noted. But preliminary observations on the whole genital system of both female and male veigaiids also reveal a resemblance to the genital system in Parasitina. Whether these findings may challenge the current status of Parasitina and/or Dermanyssina will require further investigations.