Hypotarzetta insignis was originally described in the genus Pustularia. It is supposed to be a member of the Pyronemataceae, and takes a unique position in that family, because of the unique growth mechanism concerning the transition from hypogeous to epigeous.
It was described from a plantation of Cedrus atlantica in southeastern France.
It is also unique in having white fruitbodies; most members of the Pyronemataceae have fruitbodies with orange pigments.
Hypotarzetta insignis is a striking spring fruiting species.
It is a very rare species with fragmentary distribution in the Mediterranean area. It is ectomycorrhizal with Cedrus, Abies and Pinus spp. In Spain it is known from scattered occurrences in old-growth Pinus forests that are under threat of clearcutting and other human disturbances. In Greece and Turkey it grows with Abies in natural Abies forests, which are alos threatened. In Morocco, it is native to the Cedrus atlantica forests of the Atlas. In France it seems to be least endangered, as it grows in planted Cedrus groves, and even with introduced Pseudotsuga menziesii outside the Mediterranean area.
Widespread in the Mediterranean area, but everywhere very localized and rare. Known from the Atlas mountains in Morocco, two locations in Greece, one in Turkey, several in Spain, and some disjunct locations in France.
The species is very localized in various countries around the Mediterranean. Nothing is known about the situation in northern Africa where it grows with Cedrus atlantica. It is stable in the Cedrus plantation of the Petit Lubéron in southeastern France, and was reported from a Pseudotsuga plantation in the northeast of France. In other parts of the Mediterranean it seems to be very local in small populations of only a few individuals, and growing with Pinus spp. and Abies spp.
It is not known from Italy and the Balkan, but there are two localities in Greece, and one in Turkey. Whether it occurs with Cedrus libani in Lebanon and Syria is unknown.
Population Trend: Uncertain
Ectomycorrhizal with various conifer species (notably Pinus spp., Cedrus spp., Abies spp.) in the Mediterranean Area, and also with introduced Pseudotsuga menziesii in northeastern France. Fruiting in spring. Growing in open forests and plantations, at middle elevations with sparse understory of shrubs and bushes. The forests in which the species grows are well established and old-growth. The Cedrus plantation in southeastern France was planted in 1862. Starting out hypogeous, emerging and becoming epigeous. Spore dispersal probably by wind.
The Spanish populations consist of only a few individuals each, and occur in open spaces of old-growth Pinus forests, which are under threat of clearcutting and forest management, and human disturbances.
The French populations seem not threatened, and the species seems even to spread there to other host trees.
In Turkey and Greece, Hypotarzetta is very rare, populations are small and isolated and the Abies forests in which they occur under constant threat of clearcut and overgrazing.
There is no information on the Moroccon population(s).
Berthet, P. & Riousset, L. 1963. Un Pustularia nouveau: P. insignis. Description de l’espèce et remarque sur un caractère cytologique du genre Pustularia. Bull. trimest. Soc. Mycol. France 79: 392–398.
Doll, D. & Sarraillon, F. 2013. Hypotarzetta insignis, une nouvelle espèce pour l’Alsace. Bulletin de la Fédération Mycologique de l’Est 11: 27–29.
Fouchier, F. & Neville, P. 1998. Hypotarzetta insignis, Neournula pouchetii et Geopora sumneriana, Ascomycota printaniers de la cédraie du Petit Lubéron. Bull. FAMM 13: 32–44.
Honrubia, M. & Llimona, X. 1981. Aportación al conocimiento de los hongos del S.E. de España. IV. Tres citas nuevas para la microflora-española: Pustularia insignis, Tuber borchii, Leucogaster cf. floccosus. Anales de la Universidad de Murcia 37: 81–90.
Honrubia, M. & Berthet, P. & Llimona, X. 1983. Contribution à la connaissance des champignons du Sud-Est de l’Espagne. VII. Pezizales (Ascomycètes). Bulletin Mensuel de la Societé Linnéenne de Lyon 51: 46–62.
Kaya, A. & Y. Uzun (2015). Six new genus records for Turkish Pezizales from Gaziantep Provinceg. Turkish Journal of Botany 39: 506–511.
Mateo, J.F. 2011. Hypotarzetta insignis, una especie muy rara recolectada en Cuenca. Bol. Soc. Micol. Madrid 35: 25-29.
Hypotarzetta insignis (Berthet & Riousset) Donadini. http://www.mycohellas.gr/mc/viewarticle.asp?a=1145 [accessed Feb 2018]