Gymnopilus maritimus

Gymnopilus maritimus
Scientific classification
Domain:	Eukaryota
Kingdom:	Fungi
Division:	Basidiomycota
Class:	Agaricomycetes
Order:	Agaricales
Family:	Hymenogastraceae
Genus:	Gymnopilus
Species:	G. maritimus
Binomial name
Gymnopilus maritimus Contu, Guzm.-Dáv., Ortega & Vizzini[1][2]
Gymnopilus maritimus is known only from a localised area in the Province of Olbia-Tempio, Sardinia, Italy.[3]

Gymnopilus maritimus is a fungus species of the family Hymenogastraceae first collected in northern Sardinia, Italy, in 2006. The species produces moderately sized, sturdy mushrooms of a reddish-orange colour. The cap, which can measure up to 70 millimetres (3 in) across, is covered in orange fibrils, and sometimes has small scales. The yellowish stem measures up to 110 mm (4 in) in length by 8 mm (0.3 in) in width, and sometimes shows remnants of the partial veil. The mushrooms have thick gills of a variable colour, ranging from yellow to rust but staining darker, and the yellow flesh has a mild taste. The mushrooms leave a rusty-brown spore print, while the spores themselves measure from 7.5–11.5 micrometres (0.00030–0.00045 in) in length. The species is most similar in appearance to G. arenophilus and G. fulgens, but can be differentiated from both morphologically. Despite the similarities, it is not closely related to either, suggesting convergent evolution. Instead, within the genus Gymnopilus, it is most closely related to the spectabilis–imperialis clade. However, it is not particularly similar to any of its closest relatives.

The species has been found only on coastal

Within the genus Gymnopilus, it is located in the

synonymous with G. spectabilis), G. pampeanus, and others.^[11] G. maritimus forms a more inclusive clade along with the members of spectabilis–imperialis; while it produces the smallest fruit bodies, it shares with the other members strong, sturdy mushrooms, caps with fibrils (sometimes with scales) and large, warty spores that turn red in Melzer's reagent or Lugol's iodine.^[11]

Description

External image
A photograph of Gymnopilus maritimus mushrooms, taken of the holotype and published with the original description. Hosted by Springer.

Species of fungus

Gymnopilus maritiumus Mycological characteristics
	Gills on hymenium
	Cap is convex
	Hymenium is adnate or sinuate
	saprotrophic
	Edibility is unknown

Gymnopilus maritimus mushrooms have a

mycelia are sometimes visible. It is dry, with fibres and furrows. It is a yellowish colour, bruising reddish brown.^[13] Traces of the partial veil are sometimes visible on the stem, though it does not form a ring.^[14] The yellow (brown at the bottom of the stem) flesh can be up to 15 mm (0.6 in) thick in the cap and does not bruise. It dries dark brown. There is no distinctive odour, and the taste is mild or slightly bitter.^[13] The thick gills can be adnate (connected to the stem by the entire depth of the gill) or sinuate (wavy, with the gills becoming shallower than deeper). They are subdistant (neither close nor distant) and swollen in the middle. In colour, they are yellow in the youngest mushrooms, turning an ochre-orange, while the oldest mushrooms they are rust. The gill edges are paler than the faces, and the gills stain orange-brown or darker.^[12] No reference is made in the original description to the edibility of the mushrooms.^[15]

Microscopic characteristics

Gymnopilus maritimus leaves a rusty-brown

metachromatic.^[13]

The four-spored

wine-skin. The top of the cell suddenly widens, and the cell as a whole is thin-walled, hyaline and yellowish, and sometimes appears to contain small grains.^[13] The caulocystidia (cystidia on the stem) can be found in tufts at the top of the stem, and measure from 24–60 micrometres (0.00094–0.00236 in) by 3–9 micrometres (0.00012–0.00035 in). They are cylindrical, or narrowly flask-shaped, sometimes with a long neck. They are, again, yellow and hyaline.^[3]

The yellowish

trichoderm.^[3]

Similar species

There are five species similar in appearance to G. maritimus:

heathland; further, the spores are similar in appearance to those of G. maritimus. However, G. fulgens requires soil rich in peat and must grow among moss. Moreover, there are a number of morphological differences; G. maritimus mushrooms are larger and thicker, there are never remains of the partial veil on G. fulgens stems, the shape of the top of the spores differs between the two species, and the cheilocystidia and caulocystidia are significantly larger on G. maritimus. G. fulgens var. luteicystis is even more distinct from G. maritimus than the nominate variety.^[18] Despite the similarities between the three species, the three have been shown to be in different clades within Gymnopilus, suggesting ecological convergence between G. arenophilus and G. maritimus, and morphological convergence between G. fulgens and G. maritimus.^[11]

Gymnopilus flavus, despite also appearing on land near the

Mediterranean, can be differentiated from G. maritimus as it lives among grass, especially Dactylis glomerata, and it has distinctly smaller spores, typically measuring 5 to 6 by 3.5 to 4.2 μm.^[11] G. pseudofulgens, also collected in Italy, shows two major morphological differences: it produces smaller mushrooms, and spores that are of a different shape with smaller warts. G. decipiens, another species that grows on sandy soil, again has spores that are markedly different.^[11] The American species G. arenicola also favours sandy soil, but has significantly smaller spores than G. maritimus. Two other species of Gymnopilus found around the Mediterranean are G. corsicus and G. spadiceus. G. corsicus has no veil remnants on the stem, and spores that do not turn red in Melzer's reagent or Lugol's iodine, and so can easily be differentiated from G. maritimus. G. spadiceus shows several similarities to G. maritimus, but grows only on pine wood and has rectangular spores.^[11]

Gymnopils maritimus is clearly a different species from other members of its clade, despite their close relation. All other species in the clade grow upon dead wood and have well-developed rings on their stems. The spores also differ; in the case of G. junonius and G. spectabilis (often considered synonymous), as well as G. pampeanus, they are narrower, and in the case of G. imperialis, they are wider. Of the other members of the clade, only G. junonius and G. spectabilis also grow in Europe.[11]

Habitat and distribution

Gymnopilus maritimus is known only from a single site in

high tide line.^[3] They were observed at the base of live Juncus maritimus (sea rush) plants, growing on sandy soil or decaying plants,^[3] where they were feeding as saprotrophs. As such, it is possible that the species would be able to grow on other substrates.^[16] They were observed growing from autumn to winter,^[17] between the end of October and January.^[3] In addition to the collections in Sardinia, Contu and Vizzini speculate that reports of G. fulgens growing in "sand-dune heaths" on Great Britain, an unusual habitat for that species, may in fact show the presence of G. maritimus on the island.^[17]

See also

• List of Gymnopilus species

References

1. ^ "Gymnopilus maritimus Contu, Guzm.-Dáv., A. Ortega & Vizzini". Index Fungorum. Retrieved 27 December 2010.
2. ^ "Gymnopilus maritimus Contu, Guzm.-Dáv., A. Ortega & Vizzini 2009". MycoBank. Retrieved 27 December 2010.
3. ^ ^{a b c d e f g} Guzmán-Dávalos et al. 2009, p. 200.
4. ^ Guzmán-Dávalos et al. 2009, p. 201.
5. ^ ^{a b} Contu and Vizzini 2009, p. 9.
6. ^ ^{a b c} Guzmán-Dávalos et al. 2009, p. 195.
7. ^ ^{a b} Guzmán-Dávalos et al. 2009, p. 197.
8. ^ Ambrosio E, Brotzu R, Lancellotti E, Franceschini A, Zotti M (2014). "Macrofungi in Abies alba Miller plantation in north-western Sardinia, Italy". Micologia Italiana. XLIII (1–2–3): 3–24.
9. PMID 26312049.
10. PMID 21149021
    .
11. ^ ^{a b c d e f g} Guzmán-Dávalos et al. 2009, p. 203.
12. ^ ^{a b} Guzmán-Dávalos et al. 2009, p. 198.
13. ^ ^{a b c d e} Guzmán-Dávalos et al. 2009, p. 199.
14. ^ Contu and Vizzini 2009, p. 10.
15. ^ Guzmán-Dávalos et al. 2009.
16. ^ ^{a b c} Guzmán-Dávalos et al. 2009, p. 202.
17. ^ ^{a b c} Contu and Vizzini 2009, p. 12.
18. ^ Guzmán-Dávalos et al. 2009, pp. 202–3.

Works cited

• Contu M, Vizzini A (2009). "Funghi della Sardegna: note e descrizioni – VIII. Gymnopilus maritimus e G. purpuresquamulosus, due specie rimarchevoli recentemente descritte per la Gallura" [Fungi of Sardinia: notes and descriptions – VIII. Gymnopilus maritimus and G. purpuresquamulosus, two striking species recently described from Gallura]. Micologia e Vegetazione Mediterranea (in Italian). 24 (1): 9–18.
• Guzmán-Dávalos L, Ortega A, Contu M, Vizzini A, Rodríguez A, Villalobos-Arámbula AR, Santerre A (2009). "Gymnopilus maritimus (Basidiomycota, Agaricales), a new species from coastal psammophilous plant communities of northern Sardinia, Italy, and notes on G. arenophilus".
  S2CID 38026760
  .

Further reading

• Saitta A, Bernicchia A, Gorjón SP, Altobelli E, Granito VM, Losi C, Lunghini D, Maggi O, Medardi G (2011). "Biodiversity of wood-decay fungi in Italy" (PDF).
  S2CID 84401676
  .