Pyrenula Ach. | MYCO-LICH

Pyrenula Ach.

ShareThis
The genus Pyrenula Ach. in Iran
Andre´ Aptroot
Harrie J. M. Sipman
Mohammad Sohrabi
ABL Herbarium, Gerrit van der Veenstraat 107, NL-3762 XK Soest, The Netherlands. Email: andreaptroot@gmail.com
Botanischer Garten und Botanisches Museum Berlin-Dahlem, Freie Universität Berlin, Königin-Luise-Straße 6-8, D-14195 Berlin, Germany.
Iranian Research Organization for Science and Technology.

Description

 Life habit: lichenized or non-lichenized, saprophytic;.; Thallus: crustose, usually immersed but sometimes superficial, sometimes areolate, occasionally with pseudocyphellae or pockets of crystals, often surrounded by a hypothallus; photobiont: primary one a trentepohlioid alga or absent, secondary photobiont absent; Ascomata: perithecial, black, often aggregated in pseudostromata; involucrellum: dark brown to black, clypeate, composed of fungal hyphae interspersed with bark cells and often K+ reddish or violet crystals; ascomatal wall: black, usually continuous below the hamathecium, often partly immersed in the thallus; true; exciple: brown to pale brown, entire or not developed below the perithecial cavity, colorless or orange crystals often dense at the wall lining the locule; hamathecium: initially branched, anastomosed, sparsely septate paraphysoids; then replaced by unbranched paraphyses, not anastomosing, non-amyloid, hemiamyloid or amyloid; periphyses delveloped along the ostiolar canal; asci: bitunicate, clavate to cylindrical, long-stalked, with tholus, thickened at the apex with an internal apical beak, non-amyloid; ascospores: brown, ellipsoid to fusiform, transversely 2-30-septate, or muriform, with distosepta and often additional eusepta, 9-200 x 4-55 µm; walls: not ornamented; Conidiomata: pycnidial, black; conidia: filiform, simple, hyaline; Secondary metabolites: lichexanthone, or anthraquinones, or absent; Geography: cosmopolitan, but most diverse in the tropics; Substrate: mostly on bark, but also on non-calcareous rock.; Notes: the genus is in its current delimitation characterized by the combination of clypeate ascomata and brown, distoseptate ascospores and simple paraphyses. Source: Lichen Flora of the Greater Sonoran Desert Region

Key to Species: 

Ascospores 30–36 mm long, with unequal lumina; middle lumina elongated; hamathecium

at least partly inspersed with hyaline oil globules.................................................. P. subelliptica

Ascospores <30 mm long, with equally shaped lumina; hamathecium not

Inspersed........................................................................................................... 2

2(1) Ascomata in majority 0_1–0_4 mm diam........................................................ 3

Ascomata in majority 0_4–1_2 mm diam............................................................... 6

3(2) Ascospores 23–30 mm long, with equally shaped lumina; hamathecium not inspersed........ P. chlorospila

Ascospores 7–21 mm long .................................................................................  4

4(3) Ascospores 17–21 mm long, with unequal lumina; terminal lumina closely appressed

to the outer ascospore wall .................................................................................  P. nitidula

Ascospores 7–16 mm long, with equally shaped lumina; terminal lumina separated

from the exospore by an endospore ...................................................................  5

5(4) Ascospores 11–16 mm long; ascomata c. 0_2–0_4 mm diam......................... P. aspistea

Ascospores 7–9 mm long; ascomata c. 0_1–0_2 mm diam................................... P. minutissima

6(2) Hamathecium with orange-red crystals, KOH+ purple-red soluble pigment; ascospores

20–27 mm long ..................................................................................................  P. nitida

Hamathecium without coloured crystals, KOH-- .................................................... 7

7(6) Ascospores 14–16 mm long; thallus generally olive-green............................... P. santensis

Ascospores (15–)17–22 mm long; thallus whitish grey........................................... P. laevigata