Morchella esculenta

Morchella esculenta, (commonly known as common morel, morel, yellow morel, true morel, morel mushroom, and sponge morel) is a species of fungus in the Morchellaceae family of the Ascomycota. It is one of the most readily recognized of all the edible mushrooms and highly sought after. Each fruit body begins as a tightly compressed, grayish sponge with lighter ridges, and expands to form a large yellowish sponge with large pits and ridges raised on a large white stem. The pitted yellow-brown caps measure 2–7 cm (0.8–2.8 in) broad by 2–10 cm (0.8–3.9 in) tall, and are fused to the stem at its lower margin, forming a continuous hollow. The pits are rounded and irregularly arranged. The hollow stem is typically 2–9 cm (0.8–3.5 in) long by 2–5 cm (0.8–2.0 in) thick, and white to yellow. The fungus fruits under hardwoods during a short period in the spring, depending on the weather, but it is also associated with old orchards, woods, disturbed grounds and burnt areas. Although a process was reported in 1982 to grow the fruit bodies under controlled conditions, attempts to cultivate the mushroom commercially have only been partially successful. The fungus was originally named Phallus esculentus by Carl Linnaeus in his Species Plantarum (1753), and given its current name by Swedish mycologist Elias Magnus Fries in 1801. Morchella esculenta is commonly known by various names: morel, common morel, true morel, morel mushroom, yellow morel, sponge morel, Molly Moocher, haystack, and dryland fish. In Nepal it is known as Guchi chyau. The specific epithet is derived from the Latin esculenta, meaning 'edible'. The scientific name Morchella esculenta has been applied to many similar yellow morels throughout the world. In 2014 Richard et al. used DNA analysis to restrict the M. esculenta name to a single species of yellow morel commonly found in Europe and also reported from China. Other species of yellow morel, including those in North America, have received new scientific names. The cap is pale brownish cream, yellow to tan or pale brown to grayish brown. The edges of the ridges are usually not darker than the pits, and somewhat oval in outline, sometimes bluntly cone-shaped with a rounded top or more elongate. Caps are hollow, and attached to the stem at the lower edge, and typically about 2–7 cm (0.8–2.8 in) broad by 2–10 cm (0.8–3.9 in) tall. The flesh is brittle. The stem is white to pallid or pale yellow, hollow, and straight or with a club-shaped or bulbous base. It is finely granular overall, somewhat ridged, generally about 2–9 cm (0.8–3.5 in) long by 2–5 cm (0.8–2.0 in) thick. In age it may have brownish stains near the base. It has a passing resemblance to the common stinkhorn (Phallus impudicus), for which it is sometimes mistaken. Yellow morels are often found near wooded areas. Giant centipedes make their home inside these morels, so you can identify the morel if you see a centipede inside. Infested morels usually have a hole in the top. The spores range from white to cream to slightly yellow in deposit, although a spore print may be difficult to obtain given the shape of the fruit body. The spores are formed in asci lining the pits—the ridges are sterile. They are ellipsoidal, smooth, thin-walled, translucent (hyaline), and measure 17.5–21.9 by 8.8–11.0 µm. The asci are eight-spored, 223–300 by 19–20 µm, cylindrical, and hyaline. The paraphyses are filamentous, cylindrical, 5.8–8.8 µm wide, and hyaline. The hyphae of the stem are interwoven, hyaline, and measure 5.8–9.4 µm wide. The surface hyphae are inflated, spherical to pear-shaped, 22–44 µm wide, covered by a network of interwoven hyphae 11–16.8 µm wide with recurved cylindrical hyphal ends. Fruit bodies have successfully been grown in the laboratory. R. Ower was the first to describe the developmental stages of ascomata grown in a controlled chamber. This was followed by in-depth cytological studies by Thomas Volk and Leonard (1989, 1990). To study the morel life cycle they followed the development of ascoma fruiting in association with tuberous begonias (Begonia tuberhybrida), from very small primordia to fully developed fruit bodies.