| Major Groups > True Morels and Verpas > Invalid Names > Morchella esculenta |
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Note: This page explores the taxonomic validity of the species name Morchella esculenta. If you have arrived here wanting to identify morels, please see the Classic Yellow Morel for a common and wide-spread North American yellow morel matching the "Morchella esculenta" found in field guides; see also the Key to Morels. Morchella esculenta (L.) Pers.by Michael Kuo It seems obvious that the species name Morchella esculenta must be preserved, given its universal recognition (and, perhaps, because it is the type species for the genus Morchella). However, the name cannot currently be applied in any truly scientific sense, and neotypification will be required. Perhaps this should be done with well documented, genetically distinct collections from the region of Uppsala, Sweden, in order to preserve as much of the name's heritage as possible. It is quite possible, however, that there is more than one genetically distinct (but possibly morphologically inseparable) esculenta-like yellow morel growing in Sweden; if this turns out to be the case, the most common and widespread of the Swedish esculenta taxa should be selected for the name. Whether or not any North American morels match Morchella esculenta would then depend on morphological, ecological, and genetic comparison to neotypified Swedish material. Another persepctive, however, might be that we should wait until global phylogenetic studies (at least one is in preparation) determine the probable geographic origin of the Swedish yellow morel described first by Linnaeus, and then neotypify the species from that location. Although Linnaeus collected the mushroom in Sweden, it might easily have its evolutionary roots elsewhere--even on another continent. Thus it could be argued that, if the esculenta-like yellow morels descend from what we now call "Asia" (for example), the Morchella esculenta neotype should be collected in Asia. This perspective is not very concerned with preserving the name's heritage (which might be a good thing, since taxonomic heritage is almost entirely Western and, as I have argued elsewhere, as much cultural and linguistic as "scientific") but the mushroom's heritage would be placed front and center. Below is a brief history of the species name Morchella esculenta. Phallus esculentus Linnaeus (Species Plantarum, 1753, p. 1178). Linnaeus first described Morchella esculenta, as "Phallus escuelntus," with six words: "PHALLUS pileo ovato, stipite nudo rugoso"--which my high-school Latin "training" renders as "phallus with an egg-shaped cap, stem naked [and?] wrinkled."
Morchella esculenta (L.) Persoon (Synopsis Methodica Fungorum, 1794/1801, p. 618). Persoon's description cited Linnaeus's Phallus esculentus as a precedent, and contained five words: "pileo basi contracto, stipite farcto"--roughly, "cap with a contracted base, stem stuffed"; he characterizes the genus Morchella as containing mushrooms with elongated-rounded caps that feature lacunose openings.
Morchella esculenta sensu Fries (Systema Mycologicum, 1822, p. 6). Fries cited Linnaeus's Phallus esculentus and Persoon's Morchella esculenta as precedent (along with several other previously treated morel species). His description is as follows:
Here Fries corrects Persoon's notion of a "stuffed" stem, saying it is "hollow" or "rarely stuffed when young," and expands the description of the cap surface to say that it has "frequently anastomosing ribs, without cross-ribs." In a later publication, Fries published this painting of the species, by P. Åkerlund:
Morchella esculenta (L.) Pers. sensu F. J. Seaver (The North American Cup Fungi. Operculates, 1928, p. 238.) In an early North American treatment of Morchella esculenta, Seaver's description is much more complete than the descriptions above: "Pileus subglobose, ovoid, or elongated, occasionally attenuated upwards but obtuse at the apex, varying much in size but often reaching a diameter of 4-5 cm. and a length of 7-9 cm.; pits rounded, irregular, or occasionally longitudinally elongated, yellowish within, becoming brownish or blackish when dry, reaching a diameter of 5 mm. to 1 cm.; ribs irregularly anastomozing, not longitudianlly disposed, the edges rounded, about 1 mm. thick and lighter colored than the interior of the pits, usually whitish or yellowish; stem stout but not usually exceeding two-thirds the diameter of the pileus, delicately pubescent, reaching a length of 200-250 µ [sic] and a diameter of 18-20 µ [sic]; spores 1-seriate, ellipsoid, hyaline, yellowish in mass, 12-14 X 20-24 µ; paraphyses strongly enlarged above, where they reach a diameter of 15 µ, faintly colored. "On the ground in woods and open places. "TYPE LOCALITY: Europe. "DISTRIBUTION: Massachusetts to Michigan and Colorado, south to South Carolina; probably throughout North America; also in Europe."
Morchella esculenta (L.) Pers. sensu Kellner, Renker, & Buscot (2005; Organisms, Diversity & Evolution 5: 101-107) and Wipf et al. (1999; Canadian Journal of Microbiology 45: 769-778; abstract here). Several recent European papers on esculenta-like morels have used DNA analysis to determine three putative European species in the group: Morchella esculenta sensu stricto, Morchella crassipes, and Morchella spongiola. Kellner, Renker & Buscot (2005) used sequencing and RFLP analysis of 14 collected German and French fruitbodies and 9 cultured mycelia (derived from spores of collected fruitbodies) to arrive at three DNA-defined putative species, which they also compared to morel sequences "deposited" by previous researchers in GenBank (a repository of DNA information). The authors suggest that "[s]tudies integrating morphological, ecological and molecular characterisations of a large number of samples could help to find typological factors consistent with the molecular separation" (106). Cite this page as: Kuo, M. (2006, April). Morchella esculenta. Retrieved from the MushroomExpert.Com Web site: http://www.mushroomexpert.com/morchella_esculenta.html © MushroomExpert.Com |
