Encalyptaсeae. Genus Encalypta

1. Filiform brown gemmae usually present in leaf axils; large plants; sporophytes rare or common — 2 (sect. Streptotheca)
— Filiform gemmae absent; small to large plants; sporophytes common — 3
2. Dioicous, sporophytes rare; perichaetial leaves not hair-pointed; capsules with steep, spiral furrows; spores 9-15 µm; Europe, Ural, Caucasus — 1. E. streptocarpa

In Russia the western distribution of E. streptocarpa helps to differentiate it from E. procera: when sterile the two species are morphologically nearly indistinguishable. Unfortunately, the two species have overlapping ranges in the European North, Urals, and in Eastern Caucasus. Sporophytes of E. streptocarpa are known in Russia only from the eastern slope of the Subpolar Urals. Fortunately the moderately common sporophytes in E. procera help to delimit the range of the species. Although DNA markers will distinguish the two species, in practical terms this is of little help.

— Monoicous, sporophytes common; perichaetial leaves usually hair-pointed; capsules with weak, spiral furrows; spores 14-24 µm; Arctic-mountain, circumpolar species — 2. E. procera

This species is widespread in Asian Russia in permafrost areas on calcareous substrates, but absent in the lowlands where rock outcrops are lacking. Sterile collections from areas where E. streptocarpa has not been confirmed are referred to E. procera by default.

3. Spores isopolar, rounded-tetrahedral, uniformly sculptured throughout, with papillae or almost smooth — 4
— Spores heteropolar; with radially diverging ridges on one pole and large semicircular papillae on other pole (sect. Rhabdotheca) or with latitudinal and longitudinal ridges (sect. Encalypta) — 10
4. Calyptrae gradually narrowed distally, and with irregular lobes at base; capsules spirally furrowed; peristome with filiform teeth, exostome and endostome not or only adherent at base, spreading outwards when dry — sect. Streptotheca
— Calyptrae gradually or abruptly narrowed distally, and with regular triangular lobes at base; capsules, smooth; peristome with triangular teeth, exostome and endostome completely adherent, straight when dry or peristome absent — 5 (sect. Diplolepis)
5. Peristome present — 6
— Peristome absent — 8
6. Peristome large, stout, 1/5-1/3 capsule length, bright to dark red; spores 70-95 µm; on calcareous rocks — 3. E. longicollis

A rare northern species known in Russia from calcareous areas in Taimyr, northern Yakutia, Chukotka, and from single locality in the mountains of southern Siberia. Also reported from the Caucasus. Its long, red to purplish, arching peristome teeth and large spores (over 70 µm) separate it from all other species of the genus.

— Peristome small, slender, mostly less than 1/5 of capsule length, pale orange to whitish; spores 20-50 µm; mostly on siliceous rocks — 7
7. Dorsal leaf cells at base with large, forked papillae; leaves not hyaline hair-pointed; leaf margins at mid-leaf often slightly recurved; calyptrae gradually narrowed distally, without clearly defined rostra; capsules pale throughout with red rimmed mouths; spores 23-30 µm — 4. E. affinis

Primarily an Arctic/Subarctic species in Russia, also known from a few localities in the East Caucasus. It grows mostly on neutral to ultrabasic siliceous rocks. The species can be recognized in the field by its large plant size, long, erect leaves, and rather short (ca. 1/10 of capsule length), orange peristome. Encalypta brevicollis differs in having hair-pointed perichaetial leaves and E. longicollis differs in remarkably smaller size and having a longer ( >1/5 of capsule length) peristome.

— Dorsal leaf cells at base without large, forked papillae; leaves (at least perichaetial leaves) hyaline hair-pointed; leaf margins plane; calyptrae abruptly narrowed distally with clearly defined rostra; capsules pale at base, gradually purple above, without red rimmed mouths; spores 30-42 µm — 5. E. brevicollis

A relatively rare, Arctic-alpine species in the high mountain areas of Siberia; it grows on acidic to ultrabasic siliceous rocks as well as soil. Moderately robust plants, calyptrae with fringed bases abruptly narrowed to rostra, smooth, gradually purple distally capsules and white peristomes help to identify the species in the field.

8(5). Plants small; leaf apices obtuse; costae ending below leaf apices — 6. E. mutica

The species in Genusl is rather rare in the northern Russia, although in some areas in the Siberian Subarctic it is locally frequent, e. g. , in Anabar Plateau. Encalypta vulgaris share with E. mutica eperistomate capsules and leaves with short costa, but it has dorsally smooth shiny costae and entire base of calyptrae, while in E. mutica costae are papillose, indistinct dorsally and calyptrae base is fringed.

— Plants medium-sized; leaf apices rounded, acute to acuminate; costae excurrent into a hyaline hair point or sharp, yellowish to brownish mucro — 9
9. Leaf apices gradually acute to acuminate; with yellowish to brownish mucros; calyptrae rostra rather long, long-conic or cylindric, often slightly curved — 7. E. alpina

A widespread Arctic-montane, calciphilous species, that grows in abundance only in Arctic. The presence of gradually acute to acuminate, mucronate leaves help to identify this species.

— Leaf apices rounded; with hyaline hair points; calyptrae rostra very short, short-conic, straight — 8. E. brevipes

An Arctic-montane species with a scattered distribution in Russia, it is especially characteristic of habitats with late snow melting. It can be recognized in the field by the combination of its shortly beaked calyptrae that are fringed at base, short setae (about as long as urn), absence of a peristome, and long hair-pointed leaves.

10(3). Immature setae pale yellowish, mature setae brownish; calyptrae with triangular brownish lobes at base; mature capsules smooth, brownish — (sect. Encalypta)
— Immature and mature setae red; calyptrae entire or erose at base, rarely with small, irregular whitish fringes; mature capsules smooth and pale or strongly longitudinally ribbed — 13 (sect. Rhabdotheca)
11. Peristome present; leaf margins usually recurved on one side; widespread species — 10. E. ciliata

A widespread species in southern areas of Russia, common in the Caucasus and in southern part of Siberia with a scattered distribution to the north and a few localities in the Arctic. Its medium-sized plants, fringed calyptrae, yellow setae and orange peristome help to recognize the species in the field. The stellate ornamentation of its spores is quite characteristic for the E. ciliata-group. This group includes one widespread species (E. ciliata) and two rare species (E. sibirica and E. microspora) that differ from E. ciliata in lacking peristomes.

— Peristome absent; leaf margins usually plane; species locally distributed in the Caucasus or Southern Siberia — 12
12. Costae excurrent into short yellowish mucros; calyptrae densely papillose above; basal leaf cells with mostly pale-orange longitudinal walls; xeric areas of central Asia, including Southern Siberia — 9. E. sibirica

In Russia this species is narrowly distributed in the Lake Baikal area. Encalyptra sibirica is the only Russian species in the genus, which has papillose calyptrae with fringed bases.

— Costae subpercurrent or percurrent; calyptrae nearly smooth; basal leaf cells with usually hyaline longitudinal walls; rare montane European species — 11. E. microstoma

All confirmed records for E. microstoma in Russia came from the high mountains of the Caucasus.

13(10). Peristome present — 14
— Peristome absent — 15
14. Capsules with strong, red-colored, longitudinal ribs; peristome persistent, red, usually with rudimentary exostome teeth — 12. E. rhaptocarpa

A widespread species in Russia, more common in the north than in the south. Its exact distribution is uncertain because populations previously considered an eperistomate form of E. rhaptocarpa are here treated as E. pilifera, a species with a more southern distribution.

— Capsules with weakly defined, light to orange longitudinal ribs or uniformly colored longitudinal striolations; peristome fragile, white or orange, mostly without rudimentary exostome teeth — 13. E. trachymitria

This species occurs sporadically throughout Russia. It differs from the closely related E. rhaptocarpa primarily in peristome structure (cf. Fig. 92).

15. Calyptrae very slender, transparent, undulate, not opaque and glossy, with whitish fringes at base; rare montane European species — 14. E. spathulata

This rare species is known in Russia from only four localities in its European part.

— Calyptrae stout, not transparent, smooth or somewhat uneven, not undulate, opaque and glossy, entire or eroded at base — 16
16. Leaves carinate, costae strong, shiny, golden to dark red, subpercurrent or percurrent; capsules pale, smooth — 15. E. vulgaris

A common species in the steppe zone of European Russia and the Caucasus, becoming rarer to the north, but extending to the Kola Peninsula. The distribution of E. vulgaris in Asia is unclear due to the presence of plants with characters transitional between E. vulgaris and E. pilifera. The presence of short, not excurrent costae and smooth capsules separate this species from E. pilifera, but these two characters sometimes do not correlate with each other, thus interpretation of specimens with smooth pale capsules and excurrent costae or with gametophytical characters of E. vulgaris and ribbed capsules is problematic.

— Leaves concave or slightly carinate; costae weakly differentiated, not shiny, mostly green to yellowish, excurrent as a mucro or hair point (sometimes only in perichaetial leaves); capsules with orange or red longitudinal ribs — 16. E. pilifera

A common species in Russia and the only Encalypta species in several xeric areas of Siberia. Also common in the Caucasus and known from scattered localities in other regions up to the Kola Peninsula and Taimyr Peninsula, beyond the Polar circle. Previous records of the’eperistomate form of E. rhaptocarpa’ have been referred to this species (Fedosov, 2012). Its ribbed, eperistomate capsules are diagnostic field features of the species.



SUPPLEMENTARY KEY FOR SPECIES WITHOUT DEVELOPED CAPSULES AND SPORES
1. Filiform brown gemmae usually present in leaf axils; large plants — 2
— Filiform gemmae absent; small to large plants — 3
2. Dioicous; perichaetial leaves not hair-pointed; central strand defined; upper laminal cells 9-15 µm; Europe, Urals, Caucasus — 1. E. streptocarpa
— Monoicous; perichaetial leaves usually hair-pointed; central strand well developed; upper laminal cells 12-18 µm; European North, Asian Russia — 2. E. procera
3. Leaf apices gradually acute to acuminate; costae excurrent as a yellowish or brownish mucro — 7. E. alpina
— Leaf apices acute, obtuse or rounded; costae subpercurrent, percurrent, or excurrent — 4
4. Costae subpercurrent or percurrent; leaves obtuse, rounded or rarely acute, not mucronate or hair-pointed — 5
— Costae excurrent; leaves mucronate or hair-pointed — 8
5. Stem (1-)2-5 cm long; dorsal leaf cells at base with large, forked papillae — 4. E. affinis
— Stem 0. 3-1 cm long; dorsal leaf cells at base without large, forked papillae — 6
6. Immature setae pale yellowish; calyptrae with triangular, brownish lobes at base — 11. E. microstoma
— Immature setae intensively colored, mostly reddish, calyptrae with whitish fringes or entire at base — 7
7. Costae on dorsal side obscured by subquadrate papillose cells, similar to upper leaf cells; calyptrae fringed at base; Subarctic species — 6. E. mutica
— Costae strong, shiny, golden to brown or dark red, smooth at back; calyptrae entire at base; xeric species — 15. E. vulgaris
8(4). Calyptrae fringed or split into irregular lobes at base — 8
— Calyptrae entire at base — sect. Rhabdotheca
— (mature capsules are required for species identification in this group
9. Immature setae pale yellowish — 10
— Immature setae intensively colored, mostly reddish — 11
10. Calyptrae smooth throughout; basal leaf cells with hyaline longitudinal walls; widely distributed species — 10. E. ciliata
— Calyptrae densely papillose at base; basal leaf cells with mostly colored longitudinal walls; South Siberian species — 9. E. sibirica
11. Leaves 0. 4-0. 8 mm wide, calyptrae dark bronze — 3. E. longicollis
— At least some leaves wider than 0. 8 mm; calyptrae light, golden — 12
12. Calyptrae rostra short, widely conic; leaves rather broad, 2-4x1-1.6 mm — 8. E. brevipes
— Calyptrae rostra long-conic or cylindric; leaves narrower 2-5(-6)x0.8-1.5 or 1.5-3.5x0.5-1 mm — 13
13. Calyptrae very slender, transparent, undulate, not glossy — 13. E. spathulata
— Calyptrae stout, opaque, smooth or uneven, not undulate, usually glossy — 14
14. Costae percurrent or excurrent as a short mucro; dorsal leaf cells at base with large, forked papillae; calyptrae long-conic with weakly defined rostra — 4. E. affinis
— Costae excurrent as a hyaline hair-point (at least in perichaetial leaves); dorsal leaf cells at base without large, forked papillae; calyptrae cylindric, with well defined rostra — 5. E. brevicollis