Oxneriaria immersa H. S. Asghar, R. Zulfiqar & Khalid 2023, sp. nov.
Creators: name: Zulfiqar, Rizwana
name: Asghar, Hafiza Simab
name: Khalid, Abdul Nasir
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Fungi
Ascomycota
Lecanoromycetes
Pertusariales
Megasporaceae
Oxneriaria
Oxneriaria immersa

description: Oxneriaria immersa H.S.Asghar, R.Zulfiqar & Khalid, sp. nov.
(Fig. 2)
Characterized by distinctly elongating/spreading marginal areoles, absence of prothallus, poriform-aspicilioid apothecial discs, larger ascospores (20-25 ×10-15 µm) and the presence of norstictic acid.
HOLOTYPE. — Pakistan. Khyber Pakhtunkhwa Province, Kohistan, Dassu, on calcareous rocks, 841 m a.s.l., 35°35’N, 73°37’E, 12.VII.2020, K. Habib & A.N. Khalid, KH-63 (holo-, LAH [LAH37898]; GenBank[OQ249532]).
PARATYPE. — Pakistan. Khyber Pakhtunkhwa, Swat, Miandam, on calcareous rocks, 1800 m a.s.l., 35°41’N, 72°48’E, 15.IX.2021, M. Usman, RG-15-A (para-, LAH [LAH 37911]; GenBank[OQ 152021]).
ETYMOLOGY. — The specific epithet ‘immersa’ (Latin) refers to the immersed apothecial discs.
CHEMISTRY. — K+ (yellow turning red), C–, KC–. TLC: norstictic acid.
HABITAT AND ECOLOGY. — The holotype (LAH37898) was found on calcareous rocks in a dry, temperate area, in an open situation, exposed to sun and rain. The temperature typically varies from –8 to 28°C and the annual rainfall varies between 700 and 800 mm. The topography of the area has extreme variations in elevation. The type specimen was found at an elevation of 841 m a.s.l. whereas the paratype (LAH37911) was found at an elevation of 1800 m a.s.l., in thick hilly forests of Miandam, Swat Valley, with mean maximum and minimum temperature of 30°C and –2°C, respectively.
MYCOBANK. — MB849311.
DESCRIPTION
Thallus crustose-areolate, well-defined, up to 4 cm across, pruinose, 200-400 µm thick in section. Areoles: rounded to irregular, plane to convex, 0.3-1 mm in diameter, marginally elongated/spreading giving a lobate view, up to 1.5 mm long.
Prothallus: absent. Color: dark grey when dry, greenish grey when wet. Upper cortex: dark brown, 10-15 µm thick, cells rounded, 5-9 µm in diameter. Algal layer: 40-70 µm thick, photobiont chlorococcoid, 9-12 µm in diameter. Medulla: 200-250 µm thick, white, hyphae hyaline, 3-4 µm wide. Apothecia: poriform-aspicilioid, 1-3 per areole. Disc: black, smooth, shiny, epruinose, plane to concave, 0.1-0.7 mm in diameter. Margins: indistinct. Epihymenium:brown, 10-15 µm tall. Hymenium: hyaline, 90-100 µm tall. Hypothecium: hyaline, 50-70 µm tall. Asci: hyaline, clavate, 90-130×15-20 µm. Ascospores:hyaline, subglobose to ellipsoid, 20-25 ×10-15 µm.
NOTES
Morphologically Oxneriaria immersa H.S.Asghar, R.Zulfiqar & Khalid, sp. nov. resembles O. virginea (Hue) S.Y.Kondr. & Lőkös but differs in having poriform-aspicilioid apothecial discs (vs poriform or slightly protruding), larger ascospores 20-25×10-15 µm (vs smaller, 14-22 ×9-12 µm) and a different chemistry, i.e., the presence of norstictic acid (vs no substance detected or once only with stictic acid) (Nordin et al. 2011; Halıcı et al. 2018).
Oxneriaria immersa H.S.Asghar, R.Zulfiqar & Khalid, sp. nov. is also morphologically close to O. kohistaniensis but differs in having a crustose-areolate thallus (vs verrucoseareolate), elongating/radiating marginal areoles (vs non radiating), a smaller hymenium 90-100 µm (vs 100-150 µm), sub-moniliform (vs simple) paraphyses and larger ascospores 20-25 ×10-15 µm (vs smaller, 15-20×9-12µm) (Zulfiqar et al. 2023). From Oxneriaria permutata (Zahlbr.) S.Y.Kondr. & Lőkös the new taxon differs in having an absence of prothallus (vs presence), a slightly taller hypothecium 50-70 µm (vs 40-50 µm), larger ascospores 20-25 ×10-15 µm (vs smaller, 15-22× 9-12 µm), large conidia 15-35 µm (vs 16-18 µm) and a different chemistry, presence of norstictic acid (vs no substance detected) (Nimis 2016).
Another, phylogenetically, related taxon is Oxneriaria iqbalii, which has similar thallus coloration and nearly identical size of the ascospores but the new taxon differs in having elongating/radiating marginal areoles (vs non radiating), a smaller hymenium 90-100µm (vs 130-160µm) and the presence of norstictic acid (vs no substance detected) (Zulfiqar et al. 2023). See also Appendix 1.
description: Published as part of Zulfiqar, Rizwana, Asghar, Hafiza Simab & Khalid, Abdul Nasir, 2023, New species of genus Oxneriaria S. Y. Kondr. & Lőkös (lichenized Ascomycota, Megasporaceae) from Khyber Pakhtunkhwa, Pakistan, pp. 109-116 in Cryptogamie, Mycologie 44 (8) on pages 110-112, DOI: 10.5252/cryptogamie-mycologie2023v44a8, http://zenodo.org/record/8344017