# Bulbothrix thomasiana

> Mediated Wiki article. Canonical URL: https://mediated.wiki/source/Bulbothrix_thomasiana
> Markdown URL: https://mediated.wiki/source/Bulbothrix_thomasiana.md
> Source: https://en.wikipedia.org/wiki/Bulbothrix_thomasiana
> Source revision: 1341957879
> License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/)

{{Short description|Species of lichen}}
{{Use dmy dates|date=July 2025}}
{{Use Oxford spelling|date=July 2025}}
{{Speciesbox
| image = 
| taxon = Bulbothrix thomasiana
| authority = Benatti & Marcelli (2011)
}}

'''''Bulbothrix thomasiana''''' is a species of [foliose lichen](/source/foliose_lichen) in the family [Parmeliaceae](/source/Parmeliaceae).<ref name="CoL_NSM6"/> It is a [corticolous](/source/corticolous_lichen) species that grows on tree trunks in the northern and central parts of South America. The lichen was [formally described](/source/species_description) as a new species in 2011 by lichenologists Michel Benatti and Marcelo Marcelli. The [specific epithet](/source/botanical_name) honours American lichenologist [Thomas Hawkes Nash III](/source/Thomas_Hawkes_Nash_III). The species is distinguished by its unusual vegetative structures ([isidia](/source/isidia)), which are uniquely fringed with tiny hair-like projections. It has been found [growing on tree bark](/source/corticolous_lichen) in [tropical](/source/tropical) forests across northern South America, from Venezuela and French Guiana to central Brazil and Bolivia.

==Taxonomy==

''Bulbothrix thomasiana'' was [formally described](/source/species_description) in 2011 by Michel Benatti and Marcelo Marcelli, who based the new species on a well-developed [thallus](/source/thallus) collected in 1969 on the Kweikin-ima [Tepui](/source/Tepui), [Bolívar State](/source/Bol%C3%ADvar_State_(Venezuela)), Venezuela. The authors separated it from the superficially similar ''[B.&nbsp;apophysata](/source/Bulbothrix_apophysata)'' because its vegetative propagules ([isidia](/source/isidia)) are themselves rimmed with tiny, bulb-based {{lichengloss|cilia}}—a feature otherwise known only in ''[B.&nbsp;fungicola](/source/Bulbothrix_fungicola)'' and ''[B.&nbsp;sipmanii](/source/Bulbothrix_sipmanii)''. They also pointed to its uniformly pale-brown lower {{lichengloss|cortex}}, abundant [rhizine](/source/rhizine)s the same colour as the cortex, ecoronate apothecia (with a plain, smooth margin rather than a ciliate or lobulate one), and medullary [lobaric acid](/source/lobaric_acid) chemistry as reliable differentiators.<ref name="Marcelli et al. 2011"/>

The [type](/source/type_(biology)) material of ''B.&nbsp;laevigatula'' was long thought to possess ciliate isidia, leading to confusion between that species, ''B.&nbsp;apophysata'', and the unnamed taxon that is now ''B.&nbsp;thomasiana''. Benatti and Marcelli re-examined the mixed "Leprieur 504" collections cited by earlier authors and showed that the true ''B.&nbsp;laevigatula'' has smooth isidia and a black lower surface, whereas the ciliate-isidiate fragments represent ''B.&nbsp;thomasiana''. The [specific epithet](/source/botanical_name) honours the American lichenologist [Thomas Hawkes Nash III](/source/Thomas_Hawkes_Nash_III) for his contributions to the study of {{lichengloss|parmelioid}} lichens.<ref name="Marcelli et al. 2011"/>

==Description==

The lichen forms small foliose [rosettes](/source/rosette_(botany)) up to about 4&nbsp;cm across. Its lobes ({{lichengloss|laciniae}}) are narrow (0.3–1.0&nbsp;mm wide), more or less linear, and loosely attached to the bark. Their margins are densely fringed with short (0.05–0.25&nbsp;mm), repeatedly forked {{lichengloss|cilia}} that sit on glossy black, sub-spherical bases. The upper surface is continuous, smooth and dusky grey-green, showing no pale blotches ({{lichengloss|maculae}}). On the lobe surface arise plentiful cylindrical [isidia](/source/isidia) 0.05–0.25&nbsp;mm tall; these [propagule](/source/propagule)s share the thallus colour but often carry miniature bulbate cilia, giving the isidiate areas a slightly darker cast.<ref name="Marcelli et al. 2011"/>

The [medulla](/source/medulla_(lichenology)) is white and reacts KC+ (rose) because of [lobaric acid](/source/lobaric_acid), while the {{lichengloss|cortex}} contains [atranorin](/source/atranorin) and turns yellow with [potassium hydroxide](/source/potassium_hydroxide) solution (K+ yellow). Beneath, the cortex is pale brown—almost [cream](/source/cream_(colour))—throughout, glossy and densely clothed in [rhizine](/source/rhizine)s that match its colour except for their tiny dark basal bulbs. [Apothecia](/source/Apothecia) (fruiting bodies) are uncommon but when present are flattened discs 1–3.5&nbsp;mm across with a smooth to faintly scalloped ({{lichengloss|crenulate}}) margin. The [ascospore](/source/ascospore)s are small (5–7.5 × 3–5&nbsp;μm), rounded to [ellipsoid](/source/ellipsoid), and thin-walled. [Pycnidia](/source/Pycnidia) are rare; they produce very slender, weakly spindle-shaped [conidia](/source/conidia) 5–7&nbsp;μm long.<ref name="Marcelli et al. 2011"/>

==Habitat and distribution==

''Bulbothrix thomasiana'' is [corticolous](/source/corticolous_lichen), occurring on the bark of living [trunks](/source/trunk_(botany)) in lowland to sub-[montane](/source/montane) tropical forest. Confirmed records come from the Guiana Shield ([type locality](/source/type_locality_(biology)) on the Venezuelan tepui and a nineteenth-century collection from [Cayenne](/source/Cayenne), French Guiana) and from central Brazil, where two specimens were gathered on a windswept [escarpment](/source/escarpment) near [Chapada dos Guimarães](/source/Chapada_dos_Guimar%C3%A3es), [Mato Grosso](/source/Mato_Grosso), at about 500&nbsp;m elevation.<ref name="Marcelli et al. 2011"/> It was recorded from Bolivia in 2015.<ref name="Flakus et al. 2015"/>

==References==
{{Reflist|refs=

<ref name="CoL_NSM6">{{Catalogue of Life |id=NSM6 |title=''Bulbothrix thomasiana'' Benatti & Marcelli |access-date=3 July 2025}}</ref>

<ref name="Flakus et al. 2015">{{cite journal |last1=Flakus |first1=Adam |last2=Sipman |first2=Harrie J. M. |last3=Rodriguez Flakus |first3=Pamela |last4=Jabłońska |first4=Agnieszka |last5=Oset |first5=Magdalena |last6=Kukwa |first6=Martin |last7=Meneses Q. |first7=Rosa I. |title=Contribution to the knowledge of the lichen biota of Bolivia. 7 |journal=Polish Botanical Journal |volume=60 |issue=1 |year=2015 |doi=10.1515/pbj-2015-0001 |doi-access=free |pages=81–98 [82]}}</ref>

<ref name="Marcelli et al. 2011">{{cite journal |last1=Marcelli |first1=M.P. |last2=Canêz |first2=L.S. |last3=Benatti |first3=M.N. |last4=Spielmann |first4=A.A. |last5=Jungbluth |first5=P. |author-link6=John Alan Elix |last6=Elix |first6=J.A. |year=2011 |title=Taxonomical novelties in Parmeliaceae |journal=Bibliotheca Lichenologica |volume=106 |pages=211–224 |url=https://www.researchgate.net/publication/235224715}}</ref>

}}

{{Taxonbar|from=Q28758048}}

Category:Parmeliaceae
Category:Lichen species
Category:Lichens described in 2011
Category:Lichens of South America

---
Adapted from the Wikipedia article [Bulbothrix thomasiana](https://en.wikipedia.org/wiki/Bulbothrix_thomasiana) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Bulbothrix_thomasiana?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.