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Home , Discina (fungus), Gyromitra, Helvellaceae

Paradiscina Benedix- a synonym of Fr.

Harri Harmaja

Botanical Museum, University of Helsinki, SF-00170 Helsinki, Finland

HARMAJA, H. 1976: Paradiscina Benedix- a synonym of Gyromitra Fr.- Karstenia 15: 33- 35. The status of the Paradiscina Benedix () was studied by examining the holotype of the type species of that genus, melaleuca Bres. The type specimen of that species has spores with four nuclei and a persistent strongly cyanophilic perisporium as well as excipulum of the Gyromitra type. It is concluded that Discina melaleuca (1) is a typical member of the family Dum., (2) belongs to the genus Gyromitra Fr. sensu HARMAJA 1973 and (3) is a valid species. Consequently, Paradiscina becomes a synonym of the older generic name Gyromitra. The results of the study necessitate the transfer of D. melaleuca to Gyromitra, and the following new combination is made: Gyro­ mitra melaleuca (Bres.) Harmaja. A note on the excipular anatomy of Gyromitra is also given. The family Rhizinaceae Bon. is included in Helvellaceae.

The genus Paradil>cina was created by BE­ Gocciadoro, Martio 1897 sub/Pino silvestri/ NEDIX (1969) to accommodate some species, Leg G Bresadola"), kindly lent by Naturhis­ previously included in Discina (Fr.) Fr., which toriska Riksmuseet (8) in Stockholm, yielded he thought to differ enough from the rest of the following results. The number of nuclei the species of that genus to warrant the esta­ per spore was studied by heating a thin section blishment of a new genus. Four species were of the hymenium in acetocarmine stain. In a included by him: Dil>cina convoluta Seav., D. certain number of immature spores the nuclei leucoxantha Bres., D. melaleuca Bres. and did absorb the dye satisfactorily. A preceding Paradil>cina intermedia n.sp., D. melaleuca KOH treatment of the tissue (see HARMAJA being the type. The criteria used by him to 197 4b) did not improve the staining in make a distinction between Dil>cina and Para­ this case. The number of nuclei per spore dil>cina are, however, very vague (see BENE­ proved to be four. This most important obser­ DIX 1969: 270-271) and no other taxonomist vation partly confirms the position of the spe­ working with the Pezizales has approved this cies in the family Helvellaceae Dum. (in which arrangement. The same applies to the esta­ I now include Rhizinaceae Bon., i.e. Gyromitra blishment in the same paper of another new s. lato and Rhizina Fr.). Towards maturity the genus of Benedix: Fastigiella for Gyromitra spores become enveloped by a continuous, (Neogyromitra) caroliniana (Fr.) Fr. The strongly cyanophilic sheath, or perisporium, last-named species I have already commented which first appears at spore ends. Because of in two previous papers (HARMAJA 1969 and that persistent cyanophilic perisporium, the 197 3) and considered it to belong to the genus spores represent the 'Peziza type' of HARMA­ Gyromitra Fr. s. lato, which of course implies J A 197 4a, which finally shows that this that I regard the genus Fastigiella Benedix as is a true member of Helvellaceae. The outer a synonym of Gyromitra. My comment on layer of the spore wall proper is congophilic Paradiscina has, however, been delayed since as in the Gyromitra species studied (HARMA­ only recently I studied the type specimen of JA 1976). Most spores contain oil drops, but the type species of this genus, Discina mela­ gaseous de Bary bubbles are always absent leuca. from them as observed in heated cotton blue. My examination on the holotype of Dil>cina The asci represent the most common type in melaleuca ("Discina melaleuca Bres./imatura!/ the order Pezizales: they appear operculate,

33 they mature at different times, and their v,rall neglected but very important detail in the is inamyloid and cyanophobic being rather careful studies of MCKNIGHT (1969 and thin and unspecialized also at the apex. The 1971) on Discina s. str. and two species of the contents of young asci are somewhat dextri­ Neogyromitra group is the discovery in at noid, which is a very common if not constant least the young apothecia of some species of phenomenon in Gyromitra. The excipulum a superficial and apparently ephemeral proved to be exactly of the Qyromitra type excipular layer with character of t. angularis­ both in young and mature apothecia. This prismatica and tendency to have projecting means that it is homogeneous practically cylindrical, ventricose, clavate or capitate end throughout being composed of textura intri­ cells. Now my own studies have recently cata. In places the hyphae are slightly swollen revealed that also the type species of Gyro­ being rather broad. The hyphal walls are mitra, G. esculenta (Pers.) Fr., possesses such slightly thickened, reviving well in young a layer at least when young. It is possibly apothecia and to some extent in the mature in this species even more distinct than in the ones. Cyanophilic 'septal collars' (see HAR­ above mentioned ones, and the clavate end MAJA 1973: 55) are usually scattered being cells form a true palisade in places! This narrow and not exceeding 1 [lm in breadth; character of Gyromitra is very important in in mature apothecia they may locally be showing, beside some others, the close relation­ somewhat less scarce. Their occurrence and ship between the genera Gyromitra and Hel­ kind are as in the Gyromitra species studied by vella St.-Amans; both genera are best included me; however, the possibility that they, pro­ in one family, Helvellaceae. bably due to the slightly thickened hyphal Summarizingly it can be stated that Disc ina walls, are very slightly broader than in those melaleuca Bres. is a typical member of the species cannot be excluded. The outermost family Helvellaceae and belongs to the genus hyphae of the excipulum have some tendency Gyromitra sensu HARMAJA 1973. As D. toward forming a very narrow zone of t. pris­ melaleuca is the type species of the genus matica atthe outer surface of the apothecium, Paradiscina Benedix, the latter generic name in young ascocarps slightly more clearly than becomes a synonym of the older name Gyro­ in mature ones (whether this kind of tissue is mitra. As this species is valid, it is herewith left in truly old apothecia, remains to be transferred to the genus Gyromitra: Gyro­ studied). No cyanophilic intercellular matter mitra melaleuca (Bres.) Harmaja, n. comb. is present in that area. Here and there the (Discina melaleuca Bresadola, Fungi Triden­ outermost cells are ± elongated and projecting tini II : 74. 1898.). - more often in young apothecia, especially It may be added, that neither published (?) towards their margin - but they are not Benedix the new combination 'Paradiscina specialized, or 'hairs', as their walls are ± melaleuca (Bres.) Benedix' nor 'Fastigiella hyaline, cyanophobic, smooth and not caroliniana (Fr.) Benedix' validly since in thickened or only slightly so. both cases he failed to give the appropriate The fact that I above consider an excipulum complete reference to the basionym with its at least initially ± distinctly two-layered original publication (International Code of typical of Gyromitra may appear surprising as Botanical Nomenclature, Art. 33). the current established opinion, strengthened by the study of ECKBLAD (1968), regards Acknowledgement. - I wish to thank Prof. Rolf the excipulum of Gyromitra s. lato (incl. Santesson, the Director of Naturhistoriska Riks­ Discina s. str. and Neogyromitra Imai) as one­ museet (S) in Stockholm, for arranging the loan of layered with only t. intricata. However, a the type of Disc ina melaleuca.

REFERENCES

BENEDIX, E . H. 1969: Art- und Gattungsgrenzen HARMAJA, H. 1969: A wider and more natural bei hoheren Discomyceten, III. - Kultur­ concept of the genus Gyromitra Fr. - Kar­ pflanze17:253-284. stenia 9: 9-12. ECKBLA D, F.-E. 1968: The genera of the operculate 1973: Amendments of the limits of the Discomycetes. A re-evaluation of their genera Gyromitra and , with , phylogeny and nomenclature. - the description of a new species, Gyromitra N. Mag: Bot. 15: 1-191. montana.- Karstenia 13: 48-58.

34 197 4a: Observations on the presence of a genera Gyromitra, and Otidea. - cyanophilic perispore in the spores of the Karstenia Karstenia 15:29-32. Pezizales. - Karstenia 14: 123-125. MCKNIGHT, K. H. 1969: A note on Discina. - 197 4b: The generic limit between Otidea Mycologia 61: 614-630. and Tarzetta (Pustularia auct.). - Karstenia 1971: On two species of false morels (Gyro­ 14: 138-142. mitra) in Utah.- Great Basin Nat. 31:35-47. 1976: New species and combinations in the

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