External exoskeletal cavities in Coleoptera and their possible mycangial functions

Publication Type:Journal Article
:2010
Authors:V. V. Grebennikov, Leschen R. A. B.
Journal:Entomological Science
Volume:13
Pagination:81-98
Date Published:Mar
:1343-8786
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This paper reviews the occurrence of external exoskeletal cavities in beetles and provides critical reassessment of their possible mycangial function. In most reported cases, the decision to attribute mycangial function to exoskeletal cavities was based solely on the combination of two factors: (i) observation of these cavities on beetle's body; and (ii) knowledge that this particular beetle species uses fungi as a food source. Such reasoning resulted in the assumption, occasionally premature and not supported by other evidence, that exoskeletal pits in the following families may function as mycangia: Rhysodidae, Ptiliidae, Staphylinidae, Hybosoridae, Scarabaeidae, Derodontidae, Ptinidae, Jacobsoniidae, Boganiidae, Cryptophagidae, Endomychidae, Erotylidae, Latridiidae, Nitidulidae, Phloeostichidae, Silvanidae, Sphindidae, Pyrochroidae, Anthribidae, Attelabidae and Curculionidae. We conclude that only two beetle families include species with adequately documented cases of external exoskeletal mycangia: (i) Curculionidae (some Scolytinae and Platypodinae); and (ii) the structurally complex mycangia of Attelabidae (Euops females). One or more species of Sphindidae, Erotylidae, Silvanidae, and Latridiidae have likely functional mycangia. Exoskeletal pits with uncertain function are additionally reported from the following families: Cupedidae, Ommatidae, Lepiceridae, Carabidae, Histeridae, Hydraenidae, Leiodidae, Elmidae, Artematopodidae, Throscidae, Elateridae, Rhinorhipidae, Biphyllidae, Cerylonidae, Cyclaxyridae, Monotomidae, Mycetophagidae and Zopheridae. We also discuss the transport of fungal spores and conidia by waxy exudates or debris build up on beetle exoskeleton, as well as their passive attachment to the body.

Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith