| TAXON: | Enchylium tenax (Sw.) Gray (1821) |
| RECENT SYNONYMS: | Collema tenax (Sw.) Ach (1810); C. tenax var. ceranoides (Borrer) Degel. (1954); C. tenax var. corallinum (A. Massal.) Degel. (1954); C. tenax var. vulgare (Schaer.) Degel. (1954) |
| FAMILY: | Collemataceae |
| GROWTH FORM: | Foliose, homoiomerous (gelatinous) |
| SUBSTRATES: | Basic clay, sandy and calcareous soils, including unstable soils; damp mortar |
| PHOTOBIONT: | Nostoc cyanobacterium, in chains |
| REPRODUCTION: | Apothecia, pycnidia (C. tenax var. ceranoides rarely fertile); occasionally isidia |
| ASCUS: | Clavate; apex thickened, with K/I+ pale-blue annulus and tholus; (2-)4-8 spores |
| SPORES: | Ascospores fusiform to ellipsoidal, 3-septate or submuriform, 17-26 × 6.5-10.5 µm; conidia ellipsoidal |
| NOTABLE FEATURES: | Thallus dark olive-black to brown-black; lobes numerous, thick, swelling noticeably when wet; isidia when present globose; apothecia when present same colour as thallus, recalling ‘octopus suckers’ Highly variable in form: sometimes as rosette-like tufts of simple or branching lobes, usually fertile (once known as C. tenax var. vulgare); sometimes in ‘piles’ of chunky, erect lobes, usually infertile (once known as C. tenax var. ceranoides); rarely almost crustose with lobules around apothecia (once known as C. tenax var corallinum) |
| CHEMICAL TESTS: | – |
| HABITAT: | Wherever suitable substrate available, frequently in anthropogenic habitats |
| DISTRIBUTION: | Widespread across Britain, often common |
| CONSERVATION STATUS: | Least Concern |
| LICHENICOLOUS FUNGI: | Didymellopsis pulposi |
| IDENTIFICATION DIFFICULTY: | Green 1: Field identification possible (C. tenax var. ceranoides is classified as Green 2: Field identification possible with care). |
| CONFUSION SPECIES: | – |
FIELD NOTES
To be added.
LAB NOTES
Enchylium tenax can be identified without microscopy.
SPECIMENS
Enchylium tenax (Collema tenax var. ceranoides) : England : VC54 North Lincolnshire : TF1194 : October 2025 : On mineral soil : First record for hectad : © Anthony Speca : CC BY-SA 4.0
Enchylium tenax (Collema tenax var. ceranoides) : England : VC25 East Suffolk : TM3877 : February 2025 : In soil pocket on flint pavement : First record for hectad : © Anthony Speca : CC BY-SA 4.0
Enchylium tenax (Collema tenax var. ceranoides) : England : VC28 West Norfolk : TM8742 : October 2024 : On mineral soil : © Anthony Speca : CC BY-SA 4.0
