Bulbothrix ventricosa (Hale & Kurokawa) Hale. Phytologia 28(5): 481. 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 : 14-17

Bulbothrix ventricosa (Hale & Kurokawa) Hale. Phytologia 28(5): 481. 1974. Figures 14-15

Basionym.

Parmelia isidiza var. domingensis Vainio. Annales Academiae Scientarum Fennicae 6A(7): 17. 1915.

Synonym.

Parmelia ventricosa Hale & Kurokawa. Contributions from the United States National Herbarium 36: 140. 1964. [nom. nov. for Parmelia isidiza var. domingensis Vainio]

Lectotype.

Dominican Republic, Santo Domingo, La Cumbra, ad corticem arboris, leg. C. Raunkiaer 492, 09-IV-1906 (TUR-V!, duplicate C).

Description.

Thallus sublinearly to subirregularly laciniate to sublaciniate, tuning dusky green in the herbarium, up to 8.7 cm diam., subcoriaceous to submembranaceous, corticicolous or ramulicolous; upper cortex 12.5−15.0 µm thick, algal layer 20.0−32.5 µm thick, medulla 52.5−67.5 µm thick, lower cortex 15.0−22.5 µm thick. Laciniae anisotomically dichotomously branched to irregularly ramified, (0.7-) 1.5-4.5 mm wide, contiguous to occasionally slightly imbricate in the center, weakly adnate and loosely adpressed, with flat to slightly involute, subtruncate to subrounded apices, the margins flat to slightly involute, crenate to subirregular, entire to slightly incised, rarely sublacinulate, axils oval, upper cortex usually continuous to irregularly fissured on older parts, smooth to subrugose, laminal ciliary bulbs common, scarce to abundant, usually frequent, rarely absent, mainly on young distal or less isidiate parts. Adventitious marginal lacinulae scarce on older parts, short, 0.2-0.5 × 0.1-0.2 (-0.3) mm, plane, simple or irregularly branched, apices truncate, lower side concolorous with the lower marginal zone. Maculae weak to distinct, punctiform to effigurate, laminal or in the amphithecia of the apothecia. Cilia black to occasionally whitish, with simple, frequently downward-bent, sometimes missing apices, 0.05-0.35 × ca. 0.03 mm, with emerse bulbate bases 0.05−0.15 (-0.35) mm wide, frequent along the margins in the crenulations and axils of the laciniae, spaced 0.05−0.10 mm from each other, som etimes becoming contiguous, solitary or in small groups, becoming absent or scarce at the apices of the laciniae and some parts of the margins. Soredia and pustulae absent. Isidia frequent to abundant, laminal, granular to short smooth cylindrical, straight, 0.05-0.15 (-0.25) × ca. 0.05 mm, simple to partially slightly ramified, erect, firm to slightly caducous, concolorous but partially with pale e brown apices, eciliate. Medulla white. Lower surface black with small dark brown spots, black mixed with brown in variable intermediary levels to entirely brown, shiny, smooth to rugose, partially venate, moderately rhizinate except by the margins. Marginal zone pale brown to brown or black, attenuate or indistinct from the center, shiny, 0.5-4.0 mm wide, smooth to subrugose, naked becoming rhizinate or papillate towards the center. Rhizinae black to brown, sometimes with whitish apices, simple, partially with bulbate bases, 0.05-0.30 (-0.40) × 0.03-0.05 mm, frequent, evenly distributed. Apothecia subplane to concave, adnate, 0.3-4.2 mm diam., laminal, margins crenate, coronate (bulbs appearing in the crenulations), amphithecium smooth without ornamentations. Disc brown, epruinose, imperforate, epithecium 7.5-10.0 µm high, hymenium 65.0−75.0 µm high, subhymenium 25.0−37.5 µm high. Ascospores ellipsoid to oval, 11.0−20.0 × 7.0−10.0 (−11.5) µm, epispore 1.0−1.5 µm. Pycnidia (not found on type) laminal, immerse, with brown to black ostioles; conidia bacilliform to weakly bifusiform 5.0−7.0 × 1.0 µm.

Spot tests.

upper cortex K+ yellow, UV-; medulla K+ yellow→orange or light red, C-, KC-, P+ orange, UV-.

TLC/HPLC.

cortical atranorin and chloroatranorin, medullary norstictic and connorstictic acids (examined by Jack A. Elix; see also Hale 1976, Hale and Kurokawa 1964).

Distribution.

Asia: Thailand ( Papong et al. 2007). Africa: South Africa ( Hale 1976, Hale and Kurokawa 1964), Kenya (Swinscow and Krog 1988). North America: Mexico ( Hale 1976, Hale and Kurokawa 1964). Central America and Caribbean: Costa Rica, Panama ( Hale 1976), Dominican Republic ( Vainio 1915, Hale 1976, Hale and Kurokawa 1964). South America: Venezuela ( Hale 1976, López-Figueiras 1986, Marcano et al. 1996) and Brazil: Minas Gerais ( Ribeiro 1998), São Paulo ( Ribeiro 1998, Jungbluth 2006), Pará ( Brako et al. 1985) and Paraná ( Eliasaro 2001, Eliasaro and Adler 1997).

Additional specimens examined.

Mexico, open pasture, scattered cactus and Acacia, elev. 1240 m, 9 km E of Jalapa, along highway 140, on Opuntia sp., leg. M.E.Hale & T.R.Soderstrom 19389, 13-III-1960 (DUKE). Dominican Republic, La Vega, 4.7 km S of Constanza, then 8 km toward Pinar Parejo, moist broadleaf forest along road, 6150 ft., leg. R. C. Harris 14784E, 27-IV-1982 (NY). Venezuela, Táchira, Vía Rubio, Bramón, 800-1100 m, leg. M. E. Hale & M. López-Figueiras 45727a, 24-III-1975 (US). Bolivia, Santa Cruz, Florida, Santa Rosa de Lima, Quebrada Del Crestón, 5 km E of Santa Rosa, 17°52'S, 64°15'W, 1470m, leg. M. Salidas et al. 4370b, 3-VII-1996 (NY). Uruguay, Rocha, La Esmeralda (route 9, 280.5 km), on Acacia sp., 34°12'S, 53°52'W, 800−1100 m, leg. A. Mones s.n., 25-V-1986 (US). Brazil, Pará State, Serra do Cachimbo, 842 km N of Cuiabá on Cuiabá-Santarém highway (BR-163), ca. 8°45'S, 54°57'W, ca. 350-500 m, mature Forest along stream on sandy soil with deep humus and roadbank vegetation, 5-V-1983, leg. L. Brako & M.J. Dibben 6711 (NY). Idem, Bahia State, Serra de Rega, on bark of small vochyosiaceous tree in cerrado, cerrado with occasional tree islands, ca. 23 km N of Seabra, road to Agua de Rega, elev. ca. 1000 m, leg. H.S. Irwin, R.M. Harley & G.L. Smith s.n., 24-II-1971 (NY 30946J). Idem, Minas Gerais State, Catas Altas Municipality, Parque Natural do Caraça, track to the Cascatinha, first 200 m, on small tree thin twig in mesophyllous wood, leg. M.P. Marcelli & A.E. Luchi 29789, 12-XI-1995 (SP). Idem, São Paulo State, Ibiúna Municipality, Morro Grande Neighborhood, SKY site, on small tree thin twig ( Citrus sp.) in orchard, leg. M.P. Marcelli & O. Yano 14618, 12-X-1992 (SP). Idem, Serra Negra Municipality, Alto da Serra, near the television tower, on isolate coconut tree stem in the hotel, leg. M.P. Marcelli, O. Yano & A.B. Carvalho 22480, 04-IV-1993 (SP). Idem, São Paulo Municipality, Parque Estadual da Cantareira, Núcleo da Pedra Grande, on tree trunk in illuminated woods, leg. M.P. Marcelli, A. Rezende & O. Yano 13607, 18-V-1992 (SP). Idem, Santa Catarina State, Serra Geral, Serra Rio do Rastro, ca. 12 km W of Bom Jardim da Serra on road to Lauro Muller, at rim of summit plateau, 1470 m ca. 28°22'S, 49°32'W, humid hardwoods, 27-IX-1984, leg. D.M.Vital & W.R.Buck 12370 p.p. (NY). Idem, Rio Grande do Sul State, Vacaria Municipality, Fazenda da Estrela, 28°03'46.8"S, 50°57'33.7"W, 876 m alt., on branch of Podocarpus lambertii in edge of riparian wood, leg. L.S. Canêz & A.A. Spielmann 1282, 10-I-2004 (SP).

Comments:

The holotype (Fig. 14) consists of a small thallus in good condition, growing on a sliver of bark, indicating that the lower surface has never been examined yet. The lower cortex is difficult to see without removing the thallus from the substrate, but it is apparently black at the margins and dark brown otherwise. The type has only one mature apothecium with crenate margins containing ciliary bulbs. This kind of ciliary bulbs occurs also on other thallus parts. The amphithecium is maculate and has no isidia. The isotype in C mentioned by Hale (1976) was not found by the curator of that herbarium.

One of the most distinguishing characteristics of this species are the laminal ciliary bulbs, present in variable amounts (found in almost all thalli examined). These bulbs may appear all over the lamina, most often on young parts or those devoid of isidia, being bright and having an identical size and anatomy compared to those of the marginal cilia. Except in rare cases, they usually do not show formation of apices, much like those in the margins of the amphithecia. They are more massive and opaque than the pycnidia, which tend to have opaque brown or black ostioles, and are immersed in the thallus.

All bulbs have the same oily substance and idioblasts cells ( Hale 1975, Feuerer and Marth 1997, Benati 2011), whether they are marginal, laminal or those that form the coronation of apothecia. No true pycnidia were found in the holotype.

In contrast to earlier publications (e.g., Hale 1976), the color of the lower surface was found to be not constantly black, but variable among specimens of Bulbothrix ventricosa . It ranges from almost completely black to entirely brown, or to variable in color: (a) a brown to pale brown center with brown to dark brown margins, (b) a brown to dark brown center with dark brown margins, (c) a brown to black center with dark brown margins, (d) a brown to black center with pale brown margins, (e) a black to dark brown center with pale brown margins and (f) a black center with pale brown margins.

Small specimens apparently tend to have an almost black lower surface, with dark brown margins and occasional few parts in the center, with a tendency to lighten as the thallus expands and develops. The margins of the lower cortex are initially distinct and lighter than the center until the brown color predominates on the lower surface, which usually occurs in some of the larger and older thalli.

Even with this tendency for variation apparently linked to thallus development, some developed thalli were found with a predominantly black to dark brown lower cortex, as well as some small thalli with a predominantly brown to pale brown lower cortex.

Apparently, Eliasaro (2001) was the only author to perceive the occurrence of different colors in the lower cortex, citing specimens with a variation from dark brown to black.

The discovery of the laminal bulbs and the constant citation of a black lower surface in the literature ( Hale and Kurokawa 1964, Hale 1976) originally led to the hypothesis that there was a new undescribed species close to Bulbothrix ventricosa , but the laminal bulbs and the variable colour of the lower cortex appeared to be characteristic for the species.

Bulbothrix ventricosa can be misidentified as Bulbothrix tabacina when the lower cortex is black or as Bulbothrix isidiza when it is more brownish. The three species are morphologically close and have similar spot test reactions (see differences below). Also Relicina abstrusa (Vainio) Hale has been confused with these, probably by the presence of a black lower surface, isidia, and medullary norstictic acid. Relicina abstrusa has, however, a yellowish upper cortex due to the presence of usnic acid, while the cilia have smaller bulbs in comparison to those of Bulbothrix ventricosa and are more evenly spaced and distributed along the margins. The ascospores are also smaller and rounded, 5.0-6.0 × 4.0-5.0 µm.

Vainio (1915), in describing Bulbothrix ventricosa as Parmelia isidiza var. domingensis, believed it to be a variety of Parmelia isidiza Nylander [ Bulbothrix isidiza (Nylander) Hale], which curiously has a brown lower surface, and whose medulla (which contains salazinic acid instead of norstictic) reacts similarly to the K test. He noted the apothecia "without pycnidia adorning its margins" (absence of the bulbs that form the corona), and the laminal ciliary bulbs, but understood them as pycnidia, stating that he did not find conidia.

Because the name Parmelia domingensis was already used by Acharius (1814) for a species of Anaptychia [= Heterodermia domingensis (Acharius) Trevisan], Hale and Kurokawa (1964) proposed a new name and a new status for the taxon. The authors mentioned that Parmelia ventricosa would be a Caribbean species with a disjoint locality in southern Africa, while Parmelia isidiza would be a typically African species.

Bulbothrix tabacina (Montagne & Bosch) Hale differs from Bulbothrix ventricosa by the constantly black and shiny coloration of the lower cortex, the ecoronate apothecia and by the medullary chemistry due the presence of salazinic acid. Bulbothrix isidiza differs similar to Bulbothrix tabacina , but has a overall brown lower cortex. Thalli of these species do not form laminal ciliary bulbs.

Bulbothrix cassa Jungbluth, Marcelli & Elix is morphologically similar to Bulbothrix ventricosa , but does not form laminal ciliary bulbs and its isidia are frequently ornamented with pycnidia. Bulbothrix cassa has a uniformly black lower cortex from the center to the margins, and by not forming any medullary substances (all spot tests negative).