Oxneriaria insignis R.Zulfiqar & Khalid, 2023

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, Cryptogamie, Mycologie 44 (8), pp. 109-116 : 113-115

Oxneriaria insignis R.Zulfiqar & Khalid , sp. nov.

( Fig. 3 )

Characterized by distinctly lecanorine apothecial discs, taller hymenium and hypothecium (190-230, 100-160 µm) respectively and smaller ascospores (15-21 × 9-13 µm).

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-72 (holo-, LAH [ LAH37900 ]; GenBank[ OQ249530 ]).

PARATYPE. — Pakistan. Khyber Pakhtunkhwa, Kohistan, Razika Seo Valley, on calcareous rocks, 1067 m a.s.l., 35°26’N, 73°27’E, 9.IX.2020, K. Habib & A.N. Khalid, KH-70 (para-, LAH [ LAH 37899]; GenBank[ OQ 249531]).

ETYMOLOGY. — The specific epithet ‘insignis’ (Latin) refers to the distinct lecanorine apothecial discs.

CHEMISTRY. — Thallus, K+ (yellowish green), C–, KC–; Medulla, K+ (yellow), C–, KC–. TLC: cryptostictic acid.

HABITAT AND ECOLOGY. — The holotype (LAH37900) 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 with an annual rainfall varying between 700 and 800 mm. The topography of the area has extreme variations in elevation. This species was found at an elevation of 841 m a.s.l. The paratype (LAH37899) was found at an elevation of 1067 m a.s.l, having the same habitat as the holotype.

MYCOBANK. — MB849310.

DESCRIPTION

Thallus crustose-areolate, up to 3 cm across, dull, section in thallus 250-350 µm thick. Areoles: rounded to irregular, plane to convex, 0.3-0.8 mm in diameter, more or less distinctly elongated at the margins, up to 1 mm long, 0.5 mm wide. Color: whitish grey with brownish tinge when dry, greenish grey when wet. Upper cortex: paraplectenchymatous, 10-15µm thick, cells rounded, 7-9 µm in diameter. Algal layer:70-90 µm thick, continuous, even, photobiont chlorococcoid, 6-9 µm in diameter. Medulla: 150-250 µm thick, white, hyphae hyaline, 3-4 µm wide. Apothecia:lecanorine, confluent, usually one per areole. Disc: black, plane to weakly concave, pruinose, 0.5-1 mm in diameter. Margins:thick, persistent, concolorous with thallus. Epihymenium: brown, 10-15 µm tall. Hymenium: hyaline, 190-230 µm tall. Hypothecium: hyaline, 100-160 µm tall. Thalline exciple: 80-100 µm thick. Proper exciple: indistinct. Asci: 8-spored, hyaline, clavate, 85-115×30-40 µm.Ascospores: broadly ellipsoid to ovoid, hyaline, 15-21 ×9-13 µm.

NOTES

From the phylogenetically related Oxneriaria immersa H.S.Asghar, R.Zulfiqar & Khalid , sp. nov., O. insignis R.Zulfiqar & Khalid , sp. nov. differs in having lecanorine apothecial discs (vs poriform-aspicilioid), a taller hymenium and hypothecium 190- 230 µm, 100-160 µm (vs 90-100 µm, 50-70 µm), respectively, simple paraphyses (vs sub-moniliform) and smaller ascospores 15-21 ×9-13 µm (vs 20-25×10-15 µm) ( Appendix 1). Phylogenetically, O. insignis R.Zulfiqar & Khalid , sp. nov. also makes a distinct branch from O. immersa H.S.Asghar, R.Zulfiqar & Khalid , sp. nov., further reveals its novelty ( Fig. 1 ).

Oxneriaria insignis R.Zulfiqar & Khalid , sp. nov. also resembles O. supertegens (Arnold) S.Y.Kondr. & Lőkös but the new taxon differs in having distinctly lecanorine apothecial discs (vs lecanorine-aspicilioid), absence of prothallus (vs presence), a taller hymenium 190-230 µm (vs 115-140 µm), simple paraphyses (vs sub-moniliform), smaller ascospores 15-21×9-13 µm (vs 15-25× 10-16 µm) and a different chemistry, cryptostictic acid (vs aspicilin) ( Nimis 2016).

From Oxneriaria iqbalii , the new taxon differs in having elongating/radiating marginal areoles (vs non radiating), lecanorine apothecial discs (vs aspicilioid), a taller hymenium and hypothecium 190-230 µm, 100-160 µm (vs 130-160 µm, 40-50 µm), respectively, smaller ascospores 15-21 ×9-13 µm (vs 20-26 ×10-14 µm) and a different chemistry, cryptostictic acid (vs no substance detected) ( Zulfiqar et al. 2023).

Figures

FIG. 3. — Oxneriaria insignis R.Zulfiqar & Khalid, sp. nov.(holotype): A, crustose-areolate thallus;B, apothecia; C, cross section of an apothecium;D, ascospores. Scale bars: A, 1 cm; B, 0.5 mm; C, 150 µm; D, 15 µm.

FIG. 1. — Molecular phylogenetic analysis by maximum likelihood (ML) method based on ITS sequences. Bootstrap values>50% based on 1000 replicates for ML are shown at the branches and novel sequences generated during this study are in bold.