Name: Hygrocybe acutoconica
Author: (Clem.) Singer
Citation: Lilloa 22: 153. 1951.
Deprecated Synonyms: Hygrocybe aurantiolutescens, Hygrocybe cuspidata (Peck) Hongo & Izawa, Hygrophorus cuspidatus Peck, Hygrophorus acutoconicus (Clem.) A.H. Sm., Hygrocybe acutoconica var. cuspidata (Peck) Arnolds, Hygrocybe cuspidata (Peck) Murrill, Prunulus acutoconicus (Clem.) Murrill., Mycena acutoconica Clem.
Misspellings: Hygrocybe cuspidatus
See Cantrell, S.A. and D.J. Lodge. 2000. Hygrophoraceae of the Greater Antilles: Hygrocybe, subgenus Hygrocybe. Mycological Research 104: 873-878.
H. persistens is considered to take precedence over H. acutoconica in the Index Fungorum (as of January 2009). Hygrophorus persistens is used by Largent in the Agaricales of California (1985) along with Hygrophorus acutoconicus. Largent states “The red color of the pileus is the only reliable way to separate Hygrophorus persistens from Hygrophorus acutoconicus.”
Based on this information, I’ve made both names valid and broken them apart as separate names. I’ve also updated my votes so that collections from the US are considered H. acutoconica.
Regarding other synonyms D.J. Lodge provided the following note:
“Comparisons of ITS sequences by Dr. Karen Hughes and me confirms that Hygrocybe cuspidata is a synonym of Hygrocybe acutoconica, and that Hygrocybe konradii is a distinct species.”
These notes come from Hygrocybe cuspidata (Peck) Roody when it was merged with this name:Isonym
North American Flora 1916
44. Prunulus acutoconicus (Clements) Murrill.
=Mycena acutoconica Clements, Bot. Surv. Neb. 2: 38. 1893.
Pileus submembranous, persistently conic, acute, 2.5-3 cm. broad; surface light-yellow, viscid, smooth: lamellae free, linear, ochraceous when dry: spores oblong-ellipsoid, 12 X 7-8 um: stipe long, equal, smooth, yellowish-brown, 6-7 cm. long.
Type Locality: Squaw Crofton, Nebraska
Habitat: In sand
Distribution: known only from type locality
D.J. Lodge provided the following notes:
“I found with diligent tracking of the release dates of the original descriptions that Hygrocybe acutoconica has priority over H. persistens by two months. Unpublished DNA analyses of nuclear ribosomal DNA – ITS sequences show that H. persistens (described from Europe) only differs by 3.5% from H. acutoconica, which was described from Nebraska. That is on the boarderline for separating species, and one could consider them the same or different, depending on one’s preference. However, H. persistens in the strict sense isn’t in the USA, as far as I know. Morphologically (macro- and micro-) you would be hard pressed to find differences, so I follow Boertmann in considering them synonyms, though in his earlier version (now in revision), he had followed Arnolds in assuming that H. persistens had priority over H. acutoconica, but then Arnolds and Boertmann hadn’t really tracked down the release dates, as I have.”