''Bryogomphus'' is a fungal

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

in the family

Pilocarpaceae The Pilocarpaceae are a family of crustose lichens in the order Lecanorales. The species of this family have a cosmopolitan distribution and have been found in a variety of climatic regions. Pilocarpaceae was circumscribed by Alexander Zahlbruck ...

. It is a

monospecific In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispe ...

genus, containing the single species ''Bryogomphus caribaeus''. The genus was established in 2005 when it was discovered that a previously described species did not belong in its original classification. This small lichen grows exclusively on

moss Mosses are small, non-vascular plant, non-vascular flowerless plants in the taxonomic phylum, division Bryophyta (, ) ''sensu stricto''. Bryophyta (''sensu lato'', Wilhelm Philippe Schimper, Schimp. 1879) may also refer to the parent group bryo ...

in the humid mountain forests of the Caribbean, particularly in

Guadeloupe Guadeloupe is an Overseas departments and regions of France, overseas department and region of France in the Caribbean. It consists of six inhabited islands—Basse-Terre Island, Basse-Terre, Grande-Terre, Guadeloupe, Grande-Terre, Marie-Galant ...

Taxonomy

''Bryogomphus'' was

circumscribed In geometry, a circumscribed circle for a set of points is a circle passing through each of them. Such a circle is said to ''circumscribe'' the points or a polygon formed from them; such a polygon is said to be ''inscribed'' in the circle. * Circum ...

in 2005 by

Robert Lücking Robert Lücking (born 1964) is a German lichenologist, known for his extensive research on foliicolous lichens (lichens that live on leaves) and his significant contributions to the taxonomy, ecology, and biodiversity of fungi and lichens. He e ...

, William R. Buck,

Emmanuël Sérusiaux Emmanuël Sérusiaux (born 3 October 1953) is a Belgian lichenologist. His career, spanning more than four decades, has combined both lichenology research and political aspects of nature conservation. He spent several periods working as a res ...

and Lidia Ferraro after a re-examination showed that ''Gomphillus caribaeus''—described only seven years earlier—did not belong in the

Gomphillaceae The Gomphillaceae are a family of lichen-forming fungi in the order Graphidales. Species in this family are found mostly in tropical regions. The family underwent a major molecular phylogenetics-led reorganisation in 2023, in which 17 genera were ...

. The authors moved that species to the newly erected genus as the type, thereby creating ''Bryogomphus caribaeus''.

Molecular A molecule is a group of two or more atoms that are held together by attractive forces known as chemical bonds; depending on context, the term may or may not include ions that satisfy this criterion. In quantum physics, organic chemistry, ...

data were unavailable at the time, but a suite of striking anatomical characters already set the

taxon In biology, a taxon (back-formation from ''taxonomy''; : taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular name and ...

apart from lookalikes in ''

Gomphillus ''Gomphillus'' is a genus of lichen-forming fungi in the family Gomphillaceae. Taxonomy The genus was circumscription (taxonomy), circumscribed by the Finnish lichenologist William Nylander (botanist), William Nylander in 1854, with ''Gomphillu ...

'' and '' Bapalmuia'': the apothecia are (nail-shaped) with a disc-shaped top, the

paraphyses Paraphyses are erect sterile filament-like support structures occurring among the reproductive apparatuses of fungi, ferns, bryophytes and some thallophytes. The singular form of the word is paraphysis. In certain fungi, they are part of the f ...

are richly branched and knit a lattice round each

ascus An ascus (; : asci) is the sexual spore-bearing cell produced in ascomycete fungi. Each ascus usually contains eight ascospores (or octad), produced by meiosis followed, in most species, by a mitotic cell division. However, asci in some gen ...

, and the asci themselves

stain A stain is a discoloration that can be clearly distinguished from the surface, material, or medium it is found upon. They are caused by the chemical or physical interaction of two dissimilar materials. Accidental staining may make materials app ...

deep blue with iodine (an

amyloid Amyloids are aggregates of proteins characterised by a fibrillar morphology of typically 7–13 nm in diameter, a β-sheet secondary structure (known as cross-β) and ability to be stained by particular dyes, such as Congo red. In the human ...

reaction) and match the so-called '' Sporopodium'' type. These features, together with its muscicolous ecology, were the justification for placing ''Bryogomphus'' in the Pilocarpaceae, although its precise

sister group In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree. Definition The expression is most easily illustrated by a cladogram: Taxon A and ...

inside that family remains unresolved; it differs from ''Bapalmuia'' by the net-like () paraphyses and amyloid ascus apex, and from ''Gomphillus'' by the iodine-positive asci and a excipulum.

Description

The

thallus Thallus (: thalli), from Latinized Greek (), meaning "a green shoot" or "twig", is the vegetative tissue of some organisms in diverse groups such as algae, fungi, some liverworts, lichens, and the Myxogastria. A thallus usually names the entir ...

is thin, smooth to slightly powdery () and lacks a true , giving it a greyish film on the moss it inhabits; no secondary

propagule In biology, a propagule is any material that functions in propagating an organism to the next stage in its life cycle, such as by dispersal. The propagule is usually distinct in form from the parent organism. Propagules are produced by organisms ...

s or protective skin are developed. The internal alga is a green ''

Trebouxia ''Trebouxia'' is a unicellular green alga. It is a photosynthetic organism that can exist in almost all habitats found in polar, tropical, and temperate regions.Erokhina, L. G., Shatilovich, A. V., Kaminskaya, O. P., & Gilichinskii, D. A. (2004 ...

''-type cell layer.

Apothecia An ascocarp, or ascoma (: ascomata), is the fruiting body ( sporocarp) of an ascomycete phylum fungus. It consists of very tightly interwoven hyphae and millions of embedded asci, each of which typically contains four to eight ascospores. As ...

(fruiting bodies) arise as miniature turrets that grow vertically, forming pale flanks and a dark, flat to gently convex at the tip; their shape recalls tiny drawing-pins. Under the microscope the rim () is built of thick-walled fungal cells arranged like a labyrinth and clothed externally in fine, cottony

hypha A hypha (; ) is a long, branching, filamentous structure of a fungus, oomycete, or actinobacterium. In most fungi, hyphae are the main mode of vegetative growth, and are collectively called a mycelium. Structure A hypha consists of one o ...

e. Inside, abundantly branched paraphyses weave a mesh round the very elongate asci; when stained with iodine only the asci turn a uniform blue, a diagnostic reaction for the '' Sporopodium''-type ascus. Each ascus releases thread-like

ascospore In fungi, an ascospore is the sexual spore formed inside an ascus—the sac-like cell that defines the division Ascomycota, the largest and most diverse Division (botany), division of fungi. After two parental cell nucleus, nuclei fuse, the ascu ...

s 300–400

μm The micrometre (Commonwealth English as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American English), also commonly known by the non-SI term micron, is a unit of length in the International System ...

long and 3–5 μm wide, divided by many cross-walls (

septa SEPTA, the Southeastern Pennsylvania Transportation Authority, is a regional public transportation authority that operates bus, rapid transit, commuter rail, light rail, and electric trolleybus services for nearly four million people througho ...

); no asexual

pycnidia A pycnidium (plural pycnidia) is an asexual fruiting body produced by mitosporic fungi, for instance in the order Sphaeropsidales ( Deuteromycota, Coelomycetes) or order Pleosporales (Ascomycota, Dothideomycetes). It is often spherical or inve ...

conidia A conidium ( ; : conidia), sometimes termed an asexual chlamydospore or chlamydoconidium (: chlamydoconidia), is an asexual, non- motile spore of a fungus. The word ''conidium'' comes from the Ancient Greek word for dust, ('). They are also ...

have been observed.

Habitat and distribution

''Bryogomphus caribaeus'' is a bryophilous specialist that grows directly on living moss cushions or on moss-covered bark and soil. All confirmed collections come from the

Lesser Antilles The Lesser Antilles is a group of islands in the Caribbean Sea, forming part of the West Indies in Caribbean, Caribbean region of the Americas. They are distinguished from the larger islands of the Greater Antilles to the west. They form an arc w ...

, especially the humid

montane Montane ecosystems are found on the slopes of mountains. The alpine climate in these regions strongly affects the ecosystem because temperatures lapse rate, fall as elevation increases, causing the ecosystem to stratify. This stratification is ...

forests of

Basse-Terre Basse-Terre (, ; ; ) is a communes of the Guadeloupe department, commune in the France, French overseas departments and regions of France, overseas department of Guadeloupe, in the Lesser Antilles. It is also the ''prefectures in France, pref ...

(Guadeloupe) between about 450 m and 1,000 m elevation, where the climate is perennially moist and cool under an evergreen

canopy Canopy may refer to: Plants * Canopy (biology), aboveground portion of plant community or crop (including forests) * Canopy (grape), aboveground portion of grapes Religion and ceremonies * Baldachin or canopy of state, typically placed over an a ...

. Additional records from

Saint Lucia Saint Lucia is an island country of the West Indies in the eastern Caribbean. Part of the Windward Islands of the Lesser Antilles, it is located north/northeast of the island of Saint Vincent (Saint Vincent and the Grenadines), Saint Vincent ...

and related

bryophyte Bryophytes () are a group of embryophyte, land plants (embryophytes), sometimes treated as a taxonomic Division (taxonomy), division referred to as Bryophyta ''Sensu#Common qualifiers, sensu lato'', that contains three groups of non-vascular pla ...

-rich habitats suggest a Caribbean distribution, and the genus has not yet been reported outside this region. Field records show the species restricted to mossy substrates in moist, montane forests.

References

{{Taxonbar, from=Q4981053 Pilocarpaceae Lichen genera Lecanorales genera Taxa named by Emmanuël Sérusiaux Taxa named by Robert Lücking Taxa described in 2005