NAME Palaeomycites
AGE    AGE span:  mya
K&J CLASSIFICATION (2000) Chytridiomycetes, Chytridiales; or: Zygomycetes, Endogonales; or: Oomycetes, Peronosporales.
FIGURE(S)
FIGURE REFERENCE
SPECIES, AUTHORITY Palaeomycites Meschinelli 1902, p. 9, emend.
LOCATION
ORIG DESCRIPTION* ORIGINAL DIAGNOSIS: Mycelium branched, interwoven, dichotomous, cylindrical or flat (like small tapeworms), 3-4 µm in diameter, often verrucose, with indistinct septa.

DIAGNOSIS AS EMENDED (Kalgutkar & Jansonius 2000): Mycelium of branched, more or less interwoven hyphae, generally lacking septa; hyphae commonly terminating in large round to ovoid sporangia, that rarely show any contained spores; sporangia singly, or grouped into clusters; sporangia closed by a septum, or in open connection with the hypha; sporangia may be developed as a swelling in a hypha.
COMMENTS*
PUBLICATION REFERENCE Meschinelli A. 1902. Fungorum fossilium omnium Iconographia; In Aedibus J. Galla, Vicetiae, 144 p.
K&J REMARKS Meschinelli is the author of this generic name, although he himself made reference to "Palaeomyces" Renault 1896 (which was not validly published for lack of a generic diagnosis). The two species, P. gracilis and P. major [corrected from P. majus], assigned by Renault to his genus, are the full content of Meschinelli's Palaeomycites, and Meschinelli referred to Renault's effectively (if not validly) published descriptions and illustrations, which thereby become the type material. Meschinelli used, as descriptions for these species, Latin translations of the original French descriptions of Renault.

The characteristic sporocarps (also named vesicles or even, unjustifiably, 'spores') of the mycorrhizae, or rhizophagous fungi, are easily recognized by the morphology of the large, round, stalked vesicles. These are external in the 'ectomycorrhizal' fungi, and are produced within the tissues of the host by 'endomycorrhizal' fungi. In dispersed fossil remains, generally only the outer layer of the sporocarp is preserved; thus it cannot be known whether it contained a sporangium (which could have contained zygospores or chlamydospores, of unknown size), or a large spore. Most recently, Redecker et al. (2000) discussed characteristically 'glomalean' type fungal hyphae from mid-Ordovician beds (460-455 Ma), the globose single-walled sporocarps of which were referred to as "spores."

The classification of extant forms is largely based on the relationship with the host, and the structure of the wall layers of the sporocarp. Because fossil fungal remains, studied in the context of palynology, are generally dissociated from their original host, a precise classification is virtually impossible. For this reason, Kalgutkar and Jansonius (2000) have put all later generic names for fossil mycorrhizal forms with (sub)globose sporocarps into synonymy with the first validly published generic name, Palaeomycites Meschinelli 1902. Hyphae associated with arbuscles are properly assigned to Glomites.
TYPE TYPE: none designated.
ALL NAMES (Including synonyms) Aplanosporites Kar 1979.
Palaeomyces Renault ex Kidston & Lang 1921. Phycomycites Ellis 1915
Propythium Elias 1966.
Rhizophagites Rosendahl 1943.; Palaeomycites;
SERIAL NUMBER 1204
PUBLIC COMMENTS
 *For source, see Publication Reference.