Bulbothrix chowoensis (Hale) Hale. Phytologia 28(5): 480. 1974.

Benatti, Michel N., 2012, A review of the genus Bulbothrix Hale: the species with medullary norstictic or protocetraric acids, MycoKeys 2, pp. 1-28 : 2-3

Bulbothrix chowoensis (Hale) Hale. Phytologia 28(5): 480. 1974. Figures 1-2

Basionym.

Parmelia chowoensis Hale. Phytologia 23: 343. 1972.

Holotype.

Zambia, Chowo Forest, Nyika Plateau, leg. M. Jellicoe 53, IV-1969 (BM!, isotype US!).

Description.

Thallus subirregular laciniate, turning dusky green in the herbarium, fragments up to 4.3 cm diam., coriaceous, corticicolous; upper cortex 12.5−20.0 µm thick, algal layer 15.0−25.0 µm thick, medulla 100.0−155.0 µm thick, lower cortex 15.0−25.0 µm thick. Laciniae irregularly to dichotomously branched, 1.4-3.2 mm wide, imbricate, becoming crowded in the center, adnate to slightly elevate, adpressed to loose, with flat to slightly involute, subrounded to truncate apices, margins flat to slightly involute, crenate to irregular, incised, not lacinulate, axils oval to irregular. Upper surface smooth and continuous at the distal parts, becoming subrugose and transversally cracked at the center, laminal ciliary bulbs absent. Lacinulae absent, even marginal adventitious ones. Maculae absent. Cilia black to occasionally brown, apices simple 0.05-0.30 (−0.70) × ca. 0.03 mm, with emerse bulbate bases 0.05-0.10 (-0.15) mm wide, frequent throughout the margin spaced 0.05−0.10 mm from each other but becoming more prominent in the axils, absent or scarce at the apices of the laciniae. Soredia pustulae and isidia absent. Medulla white. Lower surface almost uniformly pale brown, except for some random dark brown parts, slightly shiny, smooth to subrugose, moderately rhizinate. Marginal zone brown to dark brown, indistinct from the center, slightly shiny, smooth, slightly papillate. Rhizinae pale brown to partially dark, occasionally with blackish apices, simple, without bulbate bases, 0.10-0.70 × ca. 0.05 mm, frequent, evenly distributed. Apothecia subconcave to concave or urceolate, adnate to substipitate, 0.3-7.2 mm diam., laminal to submarginal, margin smooth to irregularly subcrenate becoming retorted and fissured when old, ecoronate, amphithecia smooth to subrugose, without ornamentations. Disc dark brown, epruinose, imperforate, epithecium 10.0-15.0 mm high, hymenium 30.0−50.0 µm high, subhymenium 7.5−17.5 µm high. Ascospores subrounded to ellipsoid, 6.0-9.0 (−10.0) × 4.5-6.0 mm, epispore ca. 1.0 mm. Pycnidia laminal to submarginal, immerse, with black ostioles. Conidia weakly to evidently bifusiform, 5.0−7.0 × 0.75 µm.

Spot tests.

upper cortex K+ yellow, UV-; medulla K−, C-, KC+ rose, P+ reddish orange, UV-.

TLC/HPLC

. cortical atranorin, medullary protocetraric and conprotocetraric acids (see also Hale 1972, 1976). Analysis made by Dr. John A. Elix showed also salazinic and consalazinic acids on the isotype. In view of the condition of the collection, I believe it is a possible contaminant from mixed fragments of other thalli, since they are much agglomerated.

Distribution.

Africa: Mozambique, Zambia ( Hale 1972, 1976).

Comments.

The holotype (Fig. 1) and the isotype (Fig. 2) consist of two fragments; the original specimen was apparently separated in half. Both type fragments are in good condition, but are still attached to a small twig which is glued to a card, making it difficult to clearly see the lower cortex. Both fragments contain well-developed apothecia and many pycnidia with mature ascospores and conidia.

Compared to the original description ( Hale 1972), the investigated type material showed some differences in the thallus anatomy. The thicknesses mentioned by Hale for the upper cortex (14.0−18.0 µm), the algal layer (10.0−15.0 µm), medulla (70.0−90.0 µm) and lower cortex (12 µm) are smaller than those found here, especially for the medulla. The ascospores found were slightly larger.

This is the only true species of Bulbothrix with medullary protocetraric acid currently known, since Bulbothrix subinflata (Hale) Hale proved to be a Parmelinopsis species ( Benatti and Marcelli 2010).

Although the ciliary bulbs of Bulbothrix chowoensis are small and not as evident as in other species of the genus, they are noticeable even with the thickening of the marginal black line, and are even more easily seen when this line is brownish. The bulbs, even when subtle, have the typical anatomical structure containing idioblast cells and an oily substance ( Hale 1975, Feuerer and Marth 1997, Benatti 2011).

Bulbothrix hypocraea (Vainio) Hale differs from Bulbothrix chowoensis by the evidently maculate upper cortex, larger and more evident bulbate cilia, larger ascospores (8.0−14.0 µm long) and by the presence of medullary salazinic acid.

Bulbothrix setschwanensis (Zahlbruckner) Hale differs in having - like Bulbothrix hypocrea - larger and more evident bulbate cilia, larger ascospores (12.0−19.0 µm long) and medullary salazinic acid.

Bulbothrix viatica Spielmann & Marcelli differs by the coronate apothecia, common and constant occurrence of laminal ciliary bulbs, larger ascospores (12.0−18.0 µm long), variable coloration of the lower cortex and by the presence of medullary norstictic acid.

Bulbothrix regnelliana Jungbluth, Marcelli & Elix differs by the coronate apothecia, the ascospores size (8.0−12.,0 µm long) and by the presence of medullary norstictic acid.

Bulbothrix subcoronata ( Fée) Hale differs in by the black lower cortex with brown margins, coronate apothecia, and smaller ascospores (5.0−7.5 × 4.0−5.5 µm).