Bulbothrix haleana Serusiaux . The Bryologist 87(1): 2. 1984.

Benatti, Michel N., 2012, A review of the genus Bulbothrix Hale: the species with medullary norstictic or protocetraric acids, MycoKeys 2, pp. 1-28 : 5-7

Bulbothrix haleana Serusiaux. The Bryologist 87(1): 2. 1984. Figures 5-7

Holotype.

Zaire, Massif du Kahuzi, un peu au nord de la piste du Kahuzi, sur le versant sud-ouest du mont, bloc rocheux (type porphyre) au ras du sol dans une lande à Erica bequaertii et Philippia benguelensis , alt. 2780 m., leg. J. Lambinon 71/Z/1356, 30-XII-1971 (LG!, isotype US!).

Description.

Thallus subirregular to partially sublinearly sublaciniate, turning light dusky gray in the herbarium, fragments up to 3.6 cm diam., coriaceous, saxicolous; upper cortex 15.0−25.0 µm thick, algal layer 37.5−52.5 µm thick, medulla 42.5−80.0 µm thick, lower cortex 20.0−30.0 µm thick. Laciniae irregularly ramified to occasionally dichotomously branched, (0.7-) 1.5-5.2 mm wide, slightly imbricate becoming partially crowded in the center, weakly adnate and loosely adpressed, with flat to involute, subrounded to subtruncate apices, the margins flat, smooth to crenate or partially irregular, entire to slightly incised, not lacinulate, the axils oval to irregular, upper cortex continuous, smooth to subrugose, occasionally with irregular cracks on older parts, laminal ciliary bulbs absent. Lacinulae absent, not even adventitious ones in older parts. Maculae punctiform, laminal, usually distinct but weaker in some parts. Cilia black or occasionally dark brown, with simple to occasionally furcate and partially downward-bent apices, 0.10-0.55 (-1.00) × 0.04-0.05 mm, usually with emerse bulbate bases (0.05-) 0.10-0.15 mm wide but partially not bulbate (bulbs aborted?), sometimes the bulbs being taken along by the apices with the cilia growth, frequent along the margins spaced 0.05−0.20 mm from each other to rarely contiguous, solitary or in small groups in the crenulations and axils, usually absent or scarce in the apices of the laciniae and adjacent areas. Soredia, pustulae and isidia absent. Medulla white. Lower surface pale brown to cream colored, sometimes with small dark brown spots in the center, slightly shiny to opaque, smooth to partially subrugose, moderately rhizinate up to the margins. Marginal zone indistinct from the center to slowly attenuate, pale brown to brown, opaque to slightly shiny, smooth, weakly to moderately rhizinate. Rhizinae light to dark brown or sometimes blackened, generally with whitish apices, simple, becoming sometimes furcate or irregularly branched, partially with bulbate bases or displaced bulbs, 0.10-0.70 (−1.30) × ca. 0.05-0.10 mm, frequent to abundant, evenly distributed. Apothecia subplane to concave, sessile to adnate or substipitate, 0.2-6.3 mm diam., laminal to submarginal, margins smooth becoming subcrenate, ecoronate, amphithecium smooth becoming rugose, without ornamentations. Disc light to dark brown, epruinose, imperforate, epithecium 10.0-15.0 µm high, hymenium 32.5−45.0 µm high, subhymenium 15.0−22.5 µm high. Ascospores ellipsoid to oval or subglobose, (5.0−) 6.0−8.0 (−9.0) × (4.0−) 5.0−7.0 µm, epispore ca. 1.0 µm. Pycnidia laminal, commonly on the distal parts of the laciniae, immersed, with black ostioles. Conidia bacilliform to weakly bifusiform, 5.0-8.0 × 1.0 mm.

Spot tests.

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

TLC/HPLC.

cortical atranorin, medullary norstictic and connorstictic acids (examined and confirmed by samples sent to Jack A. Elix; Sérusiaux 1984 mentioned medullary salazinic acid).

Distribution.

Africa. Zaire ( Sérusiaux 1984).

Comments.

Both the holotype (Fig. 5) and the isotype (Figs. 6-7) are small fragments between 1.0 and 3.5 cm in diameter. Both are in good condition, only slightly damaged, and not glued to cards, which made the investigation of the lower cortex possible. Inside the packet are small envelopes, containing very small fragments and loose/detached apothecia.

Although the species was originally described as containing medullary salazinic acid, the substance confirmed by microchemical tests and chromatography was norstictic acid. It is the only species currently known within this chemical group with ecoronate apothecia.

Sérusiaux (1984) mentioned laciniae 1.0-3.0 mm wide, but the laciniae of the type material are larger, 1.5−5.0 mm wide. As for the ascospores, the measurements obtained were 6.0-9.0 × 4.0-7.0 µm, a little larger than in the original description.

Sérusiaux (1984) also described the upper cortex as "not maculate on young lobes, becoming more or less maculate elsewhere". I found that distal parts of the younger lobes show no signs of maculae, but in most of the thallus, especially the older parts, the maculae are punctiform and dense, like those observed in species such as Bulbothrix hypocraea .

Most of the cilia present typical inflated bases, but it is not uncommon that cilia without inflated bases are occasionally found among groups of cilia with inflated bases. Interestingly, in some cilia the bulb is displaced from the base. However, it is hardly found above the first third of the cilia length. It is uncertain why some cilia have no bulbs; maybe they were aborted or maybe they are not formed until a later stage of development.

The lower cortex is almost entirely brown, and in a few small spots more restricted to the central portions of the thallus it becomes a little darker. Sérusiaux (1984) wrote that the cortex could become almost whitish in some parts, but due to colour change after longer stay in the herbarium it is difficult to confirm this assertion. Most of the rhizinae have basal or displaced bulbs.

Sérusiaux (1984) commented on the presence of black dots he supposed to be pycnidia, but he did not found sterigmata or conidia. In fact, conidia are difficult to find in the type material, but when they are found the size and shape is typical for the genus. At the first sight the pycnidia were taken for laminal ciliary bulbs or parasitic fungi, but this was proven to be incorrect.

Sérusiaux (1984) distinguished Bulbothrix haleana from other species of the genus by the saxicolous habit, the light color of the lower surface and the small size of the ascospores. Bulbothrix bulbochaeta (Hale) Hale, Bulbothrix chowoensis (Hale) Hale, Bulbothrix confoederata (W. L. Culberson) Hale, and Bulbothrix laevigatula (Nylander) Hale, which have also small ascospores (≤10 mm long), differ chemically and morphologically from Bulbothrix haleana . Other Bulbothrix species containing medullary salazinic acid were differentiated by the author mainly by the larger ascospores, ranging from 8.0−12.0 to 14.0−20.0 µm long.

Bulbothrix haleana is morphologically similar to Bulbothrix hypocraea , but can be distinguished by the corticicolous habit, ascospores size (6.0−8.0 vs. 8.0−14.0 µm long), and medullary chemistry (norstictic acid vs. salazinic acid). There is some lower cortex tone difference between the types, but it may be due to the degree of medullary norstictic and salazinic acids oxidation. The holotype of Bulbothrix hypocraea has more strongly bent cilia and is even more maculate, while the rhizinae of Bulbothrix haleana appear to be more frequently bulbate. All other characters are similar.

Bulbothrix decurtata (Kurokawa) Hale differs by the more linear laciniae, an emaculate and quite fissured upper cortex, the formation of blackish small isidia, a predominantly black lower cortex and rhizinae without basal bulbs.

Bulbothrix cinerea Marcelli & Kalb also has medullary norstictic acid, a similar pale brown lower cortex and cilia aspect, but differs from Bulbothrix haleana by the sublinear and dichotomous branched laciniae, emaculate upper cortex, simple laminal isidia with brown or blackish apices, and by the coronate apothecia.