Zoopagales
Overview
The Zoopagales as proposed by Bessey (1950) included three families: Zoopagaceae (fungi discussed here under Zoopagaceae, and Cochlonemataceae), and two families of the Trichomycetes: Harpellaceae Léger & Duboscq. and Genestellaceae Léger & Gauthier (syn.=Legeriomycetaceae Pouzier). Alexopoulos and Mims (1979) followed Duddington (1973) in including the Cochlonemataceae and the Zoopagaceae s.s. in the Zoopagales. Benjamin (1979) also placed the Piptocephalidaceae, a suggestion made earlier by Kriesel (1969), and the Helicocephalidaceae, following Mil’ko (1974), in the Zoopagales, along with the Duddington’s two families. Sigmoideomycetaceae was added to the Zoopagales based on comparison of DNA sequences (Tanabe et al., 2000) and the report that haustoria may be formed by Thamnocephalis quadrupedata (Chien, 2000). There are reviews by Drechsler (1941b) and Duddington (1955b, 1956).
These fungi are all related because of their parasitic habit, many of these taxa producing haustoria. These are also similarities in zygospore structure, especially in suspensor morphology of many taxa. Some spp. of Syncephalis (Piptocephalidaceae) produce lobed appendages that resemble similar structures formed by some taxa of Cochlonema (Cochlonemataceae). Some Cochlonemataceae and Zoopagaceae spp. produce spores similar to those formed by members of the Piptocephalidaceae. Spores in taxa of the Helicocephalidaceae are similar to those formed by Syncephalis spp. (Piptocephalidaceae)(Benjamin, 1979).
Classification
ZOOPAGALES Bessey ex R. K. Benjamin, 1979 (In Kendrick, The Whole Fungus, p. 590).
(=Zoopagales Bessey, 1950 (Morphology and Taxonomy of Fungi, p. 177); nomen nudum, without a Latin diagnosis, Art. 36.1 of the ICBN (Greuter et al., 2000).
Fungi predaceous, or endo- or ectoparasites of other fungi or small animals. Predaceous forms and ectoparasites forming haustoria within host. Somatic structures composed of a branched or unbranched simple thallus or a branched hyphal system. Anamorph composed of chlamydospores, or unispored or multispored, simple or branched merosporangia. Teleomorph consisting of more or less globose zygospores produced on differentiated or undifferentiated, apposed, more or less straight or coiled suspensors.
Type family: Zoopagaceae Drechsler ex Drechsler emend. Duddington.
KEY TO THE FAMILIES OF ZOOPAGALES
A. Spores relatively large (25-130 µm long x 7-39 µm in diam), light brown to brown; sporangiophores simple; parasitic on eggs, rarely adults, of nematodes or rotifers——-HELICOCEPHALIDACEAE
AA. Spores usually smaller (when approaching above dimensions often includes length of sterile appendages), usually whitish to yellowish; sporangiophores simple or branched; parasitic on fungi or microanimals——C
B. Fertile hyphae regularly septate, dichotomously branched, disarticulate at maturity; stalked, more or less globose, fertile vesicles form in pairs at branching point of the fertile hyphae; fertile vesicles bear pedicellate spores over its entire surface——SIGMOIDEOMYCETACEAE
BB. Fungi not as above——C
C. Haustorial parasites of fungi, mostly Mucorales, rarely on Ascomycetes or Deuteromycetes——PIPTOCEPHALIDACEAE
CC. Haustorial ectoparasites or nonhaustorial endoparasites of small animals (amoebae, rotifers, nematodes), rarely on other fungi (not Mucorales)——C
D. Predacious; mycelium developed outside the host, within which haustoria are formed——ZOOPAGACEAE
DD. Ecto- or endoparasites; haustorial or nonhaustorial; only sporulating hyphae and spores formed outside host——COCHLONEMATACEAE
Updated Jan 15, 2005