Table 2.

A key to species of Xylaria associated with termite nests and soil in Thailand.

1. Ascospores with a median germ pore, (3.6–)3.9–4.7(–5) × (2.35–)2.5–3.2(–3.5) µm	X. escharoidea
1. Ascospores with a germ slit	2
2. Stromata usually repeatedly branched, with prominent perithecial mounds, ascospores shorter than 6 µm	3
2. Stromata unbranched or sparingly branched, perithecia naked or presenting either inconspicuous or conspicuous perithecial mounds	4
3. Stromatal surface white when immature, becoming blackish at maturity; ascospores ellipsoid-inequilateral, germ slit straight spore-length or nearly on flattened side, 5.0–6.0 × 2.5–3.5 µm	X. siamensis
3. Stromatal surface dull coloured, becoming blackish at maturity; ascospores short fusoid-inequilateral, 3.5–5.0 × 2.0–3.0 µm	X. atrodivaricata *
4. Ascospores > 10 µm, germ slit straight full spore-length	5
4. Ascospores < 10 µm, germ slit straight 3/4 or full spore-length	7
5. Stromal surface whitish to greyish with black ostioles; ascospores blackish-brown,(11–)14.0–19.4 × (6.5–)7.0–10.0 µm	X. tanganyikaensis *
5. Stromatal surface blackish-brown to black with black ostioles; ascospores light brown, brown to dark brown, frequently < 14 µm	6
6. Perithecia immersed, usually with prominent perithecial mounds; ascospores ellipsoid-inequilateral with narrowly rounded ends, (10–)10.8–12.3(–13.2) × 4.5–6(–6.4) µm; apical apparatus 4–4.5 × 2–3 µm	X. conica
6. Perithecia naked or nearly so; ascospores ellipsoid-inequilateral with narrowly rounded ends, some pinched at the ends,10.3–11.6(–12) × 4.8–5.6 µm; apical apparatus 1.5–2 × 2–3 µm	X. ischnostroma
7. Stromatal surface white at maturity; ascospores 5.4–6(–6.3) × 2.4–3.0 µm, straight germ slit nearly spore-length on convex side	X. reinkingii var. microspora
7. Stromatal surface other than white, usually dull coloured at maturity	8
8. Stromata usually more or less cylindrical, often exceeding 3 mm in diameter	9
8. Stromata usually slender, fusiform to cylindrical, rarely exceeding 3 mm in diameter	12
9. Stromatal surface blackish-brown to black or dark brick; ascospores mostly longer than 5 µm	10
9. Stromatal surface ochraceous to fawn, luteous, greyish or dull black; ascospores mostly shorter than 5 µm	11
10. Perithecia presenting very conspicuous mounds, blackish-brown; ostioles conic-papillate; ascospores 7.5–9.5 × (3.2–)3.5–4.5 µm	X. sihanonthii
10. Perithecia immersed, brown; ostioles papillate; ascospores 6.7–8 × 2.8–3.7 µm	X. vinacea
11. Stromata acuminate at the apex, unbranched, ochraceous to yellowish-brown on surface; ascospores inequilateral, 4–5 × 1.8–2.5 µm	X. acuminatilongissima *
11. Stromata usually blunt or, infrequently, mucronate at the apex, greyish-brown on surface; ascospores slightly inequilateral to nearly equilateral, 3.5–5 × 2–3 µm	X. nigripes *
12. Ascospores mostly > 5 µm	13
12. Ascospores mostly < 5 µm	14
13. Stromata very thin, 0.5–1 mm broad; perithecia naked or so on, hairy; ascospores 5.8–6.8 × 2.7–3.2 µm	X. minima
13. Stromata slender, perithecia immersed, forming conspicuous mounds, without hair; ascospores (4.5–)5–6.2 × 2.2–3 µm	X. fulvescens
14. Ascospores short, fusoid, pinched at the ends	15
14. Ascospores ellipsoid-inequilateral to nearly equilateral with narrowly rounded ends	16
15. Perithecia 0.3–0.7 mm diameter, 3–4 ostioles/mm; ostioles conic-papillate; ascospores fusoid with pinched ends, 4–5(–5.7) × (2.5–)3–3.8 µm; germ slit of half-full ascospore length	X. chaiyaphumensis
15. Perithecia 0.5–0.8 mm diameter, 2–3 ostioles/mm; ostioles conic-papillate; ascospores fusoid with pinched ends, 4–5.2(–5.7) × 2.7–4 µm; germ slit full ascospore length	X. thienhirunae
16. Stromatal surface longitudinally wrinkled with long stipes, unbranched with fertile parts; ascospores 3.5–5 × 1.8–2.5 µm	X. subintraflava
16. Stromatal surface wrinkled with acuminate at apex, without fertile parts, unbranched or two-branched at apex; ascospores (3.2–)3.8–5 × (1.8–)2–2.5 µm	X. margaretae

* See Srihanant and Petcharat [10].