Myriospora, Nageli ex Uloth, 1861

Wang, Jia-Xin, Liang, Fu-Hui, Zhou, Shu-Nuo & Hu, Ling, 2025, Myriospora kunyuensis (Acarosporaceae, lichenized Ascomycota), a new species from the eastern coast of China, Phytotaxa 708 (1), pp. 68-76 : 74

Key to the species of Myriospora in the world

1. - Thallus areolate or squamulose, rounded to irregular......................................................................................................................2

- Thallus areolate centrally, elongated lobate at the margin, rosette-like or irregularly spreading......................................................... ................................................................................................................................................... M. molybdina ( Westberg et al. 2024)

2. - Apothecia with a distinctly elevated parathecial ring ......................................................................................................................3

- Apothecia without a distinctly elevated parathecial ring ...................................................................................................................8

3. - Apothecia not becoming sessile.......................................................................................................................................................4

- Apothecia becoming sessile ........................................................................................................... M. signyensis ( Purvis et al. 2018)

4. - Apothecia usually 1 per areole.........................................................................................................................................................5

- Apothecia 1–3 or more per areole ......................................................................................................................................................6

5. - Apothecial disc brown; epihymenium 10–15 μm thick; asci 80–100 × 10–20 μm ........................................................................... ................................................................................................................. M. rufescens (Ach.) Hepp ex Uloth ( Knudsen et al. 2021)

- Apothecial disc dark reddish brown; epihymenium ca. 21–30 μm thick; asci ca. 30 × 8 μm.............................................................. ......................................................................................................................................... M. westbergii ( Knudsen & Bungartz 2014)

6. - Cortex <60 μm thick, saxicolous lichen..........................................................................................................................................7

- Cortex > 60 μm thick, facultative lichenicolous lichens ................................................................. M. bullata ( Knudsen et al. 2021)

7. - Paraphyses 1.0–2.0 μm in midhymenium, tips up to 2.5 m wide; ascospores ellipsoid, ca. 2.5–3 × 1–1.5 μm................................ .................................................................................................................................................... M. rhagadiza ( Westberg et al. 2011)

- Paraphyses 1.5–2.0 μm in midhymenium, tips up to 4 μm wide; ascospores narrowly ellipsoid to ellipsoid, ca. 3–5 × 1.5–2 μm.... ...................................................................................................................................................... M. scabrida ( Westberg et al. 2011)

8. - Thallus orange to rusty red...............................................................................................................................................................9

- Thallus whitish, grey to brown or green, never with red color ........................................................................................................10

9. - Cortex 15–35 μm thick, without crystals; hymenium 130–175 μm high................................... M. dilatata ( Westberg et al. 2011)

- Cortex 60–95 μm thick, uppermost usually with small orange crystals; hymenium 180–250 μm high .............................................. ..................................................................................................................................................... M. tangerine ( Westberg et al. 2011)

10. - Thallus K+ red or yellow, producing secondary metabolites.........................................................................................................11

- Thallus K–, lacking secondary metabolites......................................................................................................................................13

11. - Thallus K+ red, norstictic acid present ..........................................................................................................................................12

- Thallus K+ yellow, stictic acid present..................................................................................................... M. kunyuensis (this paper)

12. - Thallus areolate, upper surface flat to slightly convex; thallus in section forming red needle-shaped crystals in K ........................ ................................................................................................................................................. M. smaragdula ( Westberg et al. 2011)

- Thallus areolate to subsquamulose, upper surface flat to mostly uneven and strongly convex; thallus in section not forming needle-shaped crystals in K.................................................................................................................... M. myochroa ( Westberg et al. 2011)

13. - Apothecial disc very rough; parathecium 10–30 μm wide.................................................................... M. hassei ( Knudsen 2007b)

- Apothecial disc smooth to very uneven; parathecium up to 90 μm wide................................... M. myochroa ( Westberg et al. 2011)