NAME Palaeopericonia
AGE    AGE span:  mya
K&J CLASSIFICATION (2000) Fungi Imperfecti, Amerosporae.
FIGURE(S)
FIGURE REFERENCE
SPECIES, AUTHORITY Palaeopericonia Ibañez & Zamuner 1996, p. 138.
LOCATION
ORIG DESCRIPTION* ORIGINAL DIAGNOSIS: [combined description] Mycelium immersed, organized in layers (pl. 1, figs. 1-2); composed of brown hyphae, 4.3-9.6 µm wide, septa being infrequent, walls thin and delicate with sparse rounded ornamental elements (pl. 1, fig. 6). Conidiophores micronematous, mononematous. Conidiogenous cells blastic, terminal, with a blistered end. Blastoconidia globose, brown or dark brown, with verrucose walls (pl. 1, fig. 3), 6.7-14.4 µm, formed singly or in basipetal chains of up to nine elements (pl. 1, fig. 2-5) from compact apical heads. Spherical terminal chlamydospore 37.4 x 41.3 µm, with a thick wall (2.4-3.4 µm wide), and with contracted content, with a supporting hyphal end 8.2 µm in diameter (pl. 1, fig. 6).

Etymology: from Greek palaeo- (palaios) = old, and for its similarity to the extant genus Periconia.
COMMENTS* The material studied is made up of only asexual structures represented by conidia produced on single conidiophores, not enclosed in pycnidia or acervuli (conidiomata). This allows the assignment of this material within Hyphomycetes - Moniliales. The presence of conidia and mycelium pigmented, rough-walled and conidial chains, would relate the sample studied to several Dematiaceae genera. This is supported by the black color the conidia have preserved (pl. 1, 5), that could be associated to a dark mycelium - at least when alive. The closely related genera would be Periconia, Torula, Stachybotrys, Humicola, Thermomyces and Chlamydomyces. Comparisons of these can be seen on chart 1.

Almost a dozen fossil genera have been described belonging to the Dematiaceae, among them Torulites Pia 1927. This genus, and therefore extant Torula, show affinities with our material, though it is clearly differentiated by the usually non-spherical form of the spores, and the complex organization of its conidia in profusely branched chains.

Its affinity with Periconia is established by the presence of spherical, verrucose conidia, similar in size, solitary or in simple chains (pl. 1, 4), as seen in P. laminella and P. macrospinosa (figs. 2-4). Extant Araucariaceae are invaded by members of 4 fungal groups, such as Oomycetes, Ascomycetes, Basidiomycetes and Deuteromycetes (Farr et al., 1989). Within the latter, 12 Coelomycetes genera and 8 Hyphomycetes genera have been recognized, 5 of which are Dematiaceae. Most of these genera invade leaves, causing necrosis with color changes, and in only one case do they invade the wood.

Periconia has not been described invading extant Araucariaceae. It is mainly a saprophyte, frequent in soil as well as on decomposing wood, leaves, and stems of Angiosperms.

The material studied would represent the first fossil record related to Periconia and the oldest to date of the Dematiaceae family. Probably, Palaeopericonia would represent an opportunistic saprophyte; evidence of other kinds of association has not been observed (parasites, mutualism). The action of this saprophyte is supposed to have begun after the fall of young cones, contributing to their decomposition.

The presence of Palaeopericonia suggests the existence of a warm temperate and very wet habitat.
PUBLICATION REFERENCE Ibañez CG, Zamuner AB. 1996. Hyphomycetes (Deuteromycetes) in cones of Araucaria mirabilis (Spegazzini) Windhausen, Middle Jurassic of Patagonia, Argentina; Mycotaxon, v. 59, p. 137-143.
K&J REMARKS
TYPE TYPE: Palaeopericonia fritzschei Ibañez & Zamuner 1996, p. 138, pl. 1, figs. 1-6.
ALL NAMES (Including synonyms) Palaeopericonia;
SERIAL NUMBER 1222
PUBLIC COMMENTS
 *For source, see Publication Reference.