Teleomorph: ascomata 35-80 x 5-8 mm, cylindric-clavate to narrowly clavate, often somewhat laterally compressed, the apex obtuse, black (glossy when fully hydrated). Fertile part not clearly differentiated from the stipe, occupying the upper part of the ascoma and extending to around one third of its length. Stipe 1.5-3.5 mm diam., terete, dark brown to fuliginous, not viscid, minutely furfuraceous or rugulose. Interascal tissue composed of filiform paraphyses 3-4 µm diam., longer than the asci and not strongly adherent, not curved or coiled at the apex, rather thin-walled, pale brown throughout, not closely septate and not or slightly constricted at septa below, the apical cells varied in form, usually slightly enlarged, narrowly clavate to pyriform, the terminal cell sometimes globose. Asci 140-180 x 15-18 µm, cylindric-clavate to clavate, mostly slightly attenuated towards the rounded apex, fairly thick-walled but not fissitunicate, with a J+ apical pore, 8-spored. Ascospores arranged in parallel, 60-80 x 4.5-6 µm, straight or somewhat curved, narrowly cylindric-clavate with a rounded apex and tapering obtuse base, dark brown early in development, almost always 7-septate, fairly thick- and smooth-walled, without a gelatinous sheath or appendages.
Not formally assessed for GB&I. It was not listed in the provisional RDL (Evans et al. 2006) but listed as Vulnerable by Ing (1992). Its status has been assessed as Data Deficient on a global basis by Minter & Cannon (2015).
It is known from only seven sites scattered throughout GB&I, the most recent one from Cumbria - the first English locality and found as part of the Lost & Found Fungi project.
Lack of data makes threat assessment problematic, but the Geoglossaceae are highly susceptible to nitrification, and G. uliginosum in particular may be vulnerable to changing water regimes associated with climate change.
Diagnostic features include the entirely viscid fruit-bodies and the consistently 7-septate ascospores that are pigmented at an early stage within the ascus.
Currently known from sites in the following vice-counties: England (VC69 Westmorland), Northern Ireland (VCH33 Fermanagh, VCH36 Tyrone, VCH40 Londonderry), Scotland (VC96 Easterness, VC98 Argyll) and Wales (VC44 Carmarthen).
Found in boggy places and streamsides amongst Sphagnum mosses, also reported from both acidic and calcareous grassland. Further research on habitat preference would be useful.