Home
 

The European and North-American species of Sarcoscypha

H.O. Baral, Tübingen, 2004

introduction

general remarks, vital taxonomy

  

 

 

 

CONTENTS

morphology

apothecia (with images)

asci and ascospores (with images)

paraphyses (incl. pigments), excipulum & hairs (with images)

ascospore germination, anamorphs, substrate colonization

ecology

water supply, phenology, tolerance

host specifity, plant communities

geographic distribution (with map of Central Europe)

taxonomy

key to the seven European and N-American taxa

phylogeny within Sarcoscypha

accepted and excluded taxa, references

 

 

 

Introduction

 

General remarks

Sarcoscypha, the type genus of the family Sarcoscyphaceae (Pezizales, operculate discomycetes, Ascomycotina), is well known in Great Britain as “scarlet-cups” by its bright scarlet- or purple-red discs, “perhaps the most beautiful of British ascomycetes” (Dennis 1978). The genus is widespread in north temperate and boreal regions, but also occurs in (sub)tropical areas and in the southern hemisphere. To the present knowledge, about 18 species can tentatively be accepted world-wide, about 6 of which occur within Europe and N-America. Many appear to be endemic to volcanic islands in the subtropics. Though quite a high number of species (about 60) have ever been combined in the genus Sarcoscypha, many of these remained virtually unknown as they were often only collected a single time, and especially the old descriptions are very inadequate. Often redescriptions of the type material, if any exists, are lacking. Many of the taxa have later been found to belong in other genera of the Sarcoscyphaceae, or were referred to other families of the Pezizales, some even to the Helotiales.

Unlike most Pezizales, the members of the Sarcoscyphaceae grow as saprophytes on dead woody plant material (rarely woody fruits), in the case of Sarcoscypha on mostly damp, mossy branches of broad-leaved, very rarely coniferous trees, that were fallen to the ground. Most species of Sarcoscypha fruit in winter and early spring, and are often already mature when still covered by snow.

 

Vital taxonomy

Although microscopical differences observed in living specimens has indicated since about 1900 the existence of several, macroscopically indistinguishable taxa within the temperate to alpine-boreal zone of the northern hemisphere (Europe and North America), only one large-cupped species of Sarcoscypha, S. coccinea, has currently been recognized in this large area during many later decades. The diagnostic microscopical characters supporting existence of different taxa mainly concern (1) striking differences in the guttule (lipid) pattern of living ascospores, first observed by Boudier (1903), (2) a very different germination behaviour of the ascospores among collections (with or without forming conidia), first observed by Rosinski (1953, corresponding case reported by Paden 1974 in Phillipsia), and (3) differently shaped spore ends. Strong differences in conidial size were later observed in pure culture, and DNA sequences supported existence of different taxa.

Baral (1984, Central Europe), Harrington (1990, USA), Butterfill & Spooner (1995, Great Britain), Pidlich-Aigner (1999, Austria), Öpik et al. (2000, Estland), G. & Y. van Duuren (2003, 2004, Netherlands), Matočec & Kušan (2007, Croatia) and B. & O. Perić (2007) confirmed the observations of Boudier and Rosinski, and showed that totally four different large-cupped species exist in Europe and N-America (S. austriaca, S. coccinea, S. dudleyi, S. jurana, apothecial diameter 20-90 mm), three of them in Europe. Both geographical distribution and host specifity differ severely among these species. Two further species deviating by smaller apothecia and also smaller ascospores exist in that area. One is perhaps endemic to the Macaronesian islands (S. macaronesica, unclear forms intermediate to S. coccinea appear to be characteristic of the eumediterranean belt). The other species occurs in atlantic and continental N-America east of the Rocky Mts. (S. occidentalis).

Both lipid pattern and germination behaviour are vital characters, which means that they are difficult or impossible to observe in dead herbarium material: (1) ascospore guttulation severely alters in dead spores by fusion of the oil drops, and (2) presence of germinated ascospores in fruit-bodies strongly depends on the development stage of the preserved collection. Fresh samples can be kept moist until spores germinate abundantly. If dried samples show fused oil drops and do not contain germinated spores, the differences between the species bescome quite obscure. As a consequence, herbarium taxonomists like Le Gal (1941) were unable to confirm the differences as reported by Boudier and Rosinski.

Harrington (1990: 436) wrote: “The importance of fresh material for species diagnosis, especially for noting ascospore guttulation, cannot be overstated. Although I had examined material (dried herbarium specimens) from western North America I was not prepared to recognize that group as a species distinct from the two, large eastern North American species until I saw fresh (living) material.” Sarcoscypha represents one of the numerous examples of fungal genera in which a sound taxonomy is only achieved on the basis of vital macro- and especially microscopical characters gained from the study of fresh collections (“vital taxonomy”).

 

Home