Streblotrichum P. Beauv., Mag. Encycl.

Ignatov, M. S., Ishchenko, Yu. S., Kuznetsova, O. I., Fedorova, A. V. & Ignatova, E. A., 2024, The genus Streblotrichum (Pottiaceae, Bryophyta) in Russia, Arctoa 33 (2), pp. 210-225 : 218-223

Streblotrichum P. Beauv., Mag. Encycl. 9(5[19]): 317. 1804.

Plants small to medium-sized, in dense or loose tufts, green or yellow-green. Stems usually unbranched, evenly foliate. Leaves straight, curved, flexuose or contorted when dry, patent when wet, long-ligulate or oblong lanceolate, base broadened and sheathing or not distinctly sheathing, upper part flat or keeled, laminae between costa and margin flat or arching-recurved; margins plane or weakly recurved below, rarely recurved almost throughout; apex broadly acute to rounded, entire or apiculate; costa vanishing 1–6 cells below the apex, papillose on dorsal and ventral surfaces, in transverse section with dorsal stereid band, ventral stereid band weak or often absent in weaker developed plants; laminal cells rounded-quadrate, densely papillose on both leaf surfaces, with low C-shaped papillae; basal cells rectangular, smooth, at transition to upper lamina papillae are remote and round. KOH reaction yellow-orange to reddish. Specialized asexual reproduction by large, spheric to elliptic, red-brown rhizoial tubers. Dioicous. Perichaetial leaves with sheathing bases, tightly embracing the seta base, distally obtuse or contracted into narrow acumina. Male plants small, among female ones. Setae long, stramineous, reddish-yellow or

H 100 µm I F 5 mm E G D 2 mm M C A B Q

N R J K L O P 50 µm S 1 mm T

U V W X Y Z AA BB CC DD

reddish. Capsules erect, cylindric. Opercula conic and tapered to rostrum, altogether usually as long as the urn. Annuli well-developed, readily revoluble. Perisome teeth split into ca. 32 filiform branches, spirally twisted, papillose on both surfaces. Spores small.

1. Streblotrichum jacuticum (Ignatova) Ignatova , comb. nov. — Barbula jacutica Ignatova, Arctoa , 10: 161. f. 1–2. 2001.

Type: East Siberia, Republic Sakha / Yakutia , UstMaya District , Allakh-Yun , Tarbagannakh , 61°06'N – 138°10'E, 1000 m alt., along old road, 24.VIII.2000 M . Ignatov 00-1060 (holotype MHA!) .

Description. Plants in loose tufts or growing by individual plants. Stems 1–3 mm long, upper leaves larger and crowded. Leaves differentiated in size and shape, upper leaves 1.2–1.6× 0.3–0.5 mm, with differentiated ovate base, rather abruptly contracted to lanceolate acumen, apically broadly rounded; lower leaves ca. 0.5× 0.15 mm, oblong-ovate, apically acute; laminae between costa and margin strongly arching-recurved; margins plane or recurved at transition from base to acumen, entire; costa in upper stem leaves leaves up to 70 µm wide, in transverse section ventral stereid band small in lower part of better developed leaves, otherwise absent; upper and median laminal cells 6–9(–10) µm in leaves with round- ed apex, in smaller acute leaves near stem base cells larg- er, to 12–13 µm, densely papillose, papillae C-shaped; basal cells in larger leaves to 30–65×8–14(–20) µm, with length to width ratio 2.5–7:1. Rhizoidal tubers 70–100(– 120) µm. Perichaetial leaves up to 2.0× 0.7 mm, with broad base moderately tightly appressed to seta, contract- ed to a linear acumen, in inner perichaetial leaves as long as the basal part. Setae 10–16 mm, red. Capsules 0.9–1.3× 0.4 mm. Spores 11–14 µm.

Distribution and ecology. This species is known from two localities in Yakutia and one locality in Anabar Plateau in the southern Taimyr. The type collection was gathered of humus-rich soil bank along abandoned roadside near the tree line; it includes only few plants. Subsequently we found a large population of this species, where it is occurring here and there over 5 km of the valley of a small creek Segenyakh (also called Rossomakha) in Sette-Daban Range in East Yakutia, at 450–600 m elev. This is a calcareous area, with large Andreaeobrym population in the upper course of this creek ( Ignatov et al., 2016). In this area a population of S. convolutum was also found, but the latter species grows mostly along the cross-country road, whereas S. jacuticum is not weedy at all, occurring on somewhat eroded banks in floodplain and on bare soil patches at forest edges along old, little used forest roads and trails.

Specimens examined: see Table 1.

2. Streblotrichum enderesii (Garov.) Loeske, Hedwigia 49: 30. 1909. — Barbula enderesii Garov., Bryol. Austr. Excurs. 37. 1840.

Figs. 2 E2 , 3 E 2 , 4 E 2 , 5 E 2 , 6 E 2 , 8 .

Description. Plants small or medium-sized, in loose tufts, green or yellow-green. Stems 2–10 mm long, evenly foliate. Leaves 1.0–1.5× 0.2–0.35 mm, ovate-oblong, broader base moderately differentiated or not differentiated, sometimes with indistinct constriction above the base, with parallel margins in the middle and gradually tapered to triangular apical part in larger leaves, or round- ed and apiculate at apex in smaller leaves; laminae between costa and margin plane or moderately arching-recurved; margins plane, or recurved in lower half and plane above, or recurved at transition from base to acumen; in larger leaves often slightly undulate, wavy and coarsely denticulate; costa 30–50 µm wide near the base, in transverse section usually without ventral stereid band or, rarely, with 1–2 cells with narrow lumen; upper and median laminal cells in larger leaves 11–17 µm, in smaller leaves 8–11 µm, densely papillose, papillae C-shaped; basal laminal cells in larger leaves to 40–65×10–20 µm, with length to width ratio 2–4(–5):1, in smaller leaves basal cells fewer, short rectangular, with length to width ratio 1.3–3:1. Rhizoidal tubers 150–220 µm, scattered or exceedingly abundant. Perichaetial leaves up to 2× 0.6 mm, with broad base more or less tightly appressed to seta, contracted to triangular-lanceolate acumen about twice shorter than the basal part. Setae 10–16 mm, reddish-yellow. Capsules 1.1–1.3× 0.4 mm. Spores 8–10 µm.

Distribution and ecology. This mainly European species was already known in Asia ( Uzbekistan and Kyrgyzstan, see Discussion above). Its finding in geographically distant localities in Russia extends considerably its known distribution area. On Chusovaya River S. enderesii was collected on soil bank in the forest with high forbs in wet depression between limestone cliffs. In Altai it grew on eutrophic meadow with Trollius asiaticus on E-facing slope. InYakutia it was found below high limestone cliffs near the bank of Lena River, on soil banks above pebble bar, and in Ussurijsky Reserve it grew on concrete foundation of destroyed building at the bank of a stream.

Specimens examined: Table 1.

3. Streblotrichum taimyrense Ignatova & Ignatov , species nova. Figs. 2T , 3T , 4T , 5T , 6T , 9 .

Diagnosis: Differs from S. convolutum in larger spores, 11–14 µm vs. 8–10; perichaetial leaves with triangular-lanceolate acumina up to half the leaf base length vs. obtuse, with short apiculi; and smaller laminal cells, 6– 8(–10) µm vs. 8–10 µm.

Type: [ Russia], Krasnoyarsk Territory, Taimyr Distr., Khatanga settl. outskirts, Ereechka river upper course, Nyamakit-Daldyn creek mouth, Ereechka river valley 1 km downstream Nyamakit-Daldyn mouth. Eroded slope of 1-st terrace, on loamy ground. 02.VIII.[20]13. Coll. Fedosov V. E . 13-3-0725 (holotype MHA9005045 ) .

Description. Plants small, growing usually as scattered individuals or in loose tufts, yellow-green or brown-green. Stems 1–3 mm long, evenly foliate or upper leaves somewhat crowded, central strand present. Leaves in upper stem parts 1.2–1.5(–1.8)× 0.3–0.5 mm, from a distinctly differentiated, broader bases gradually or +abruptly narrowed into lanceolate, broadly acute or blunt acumina; laminae between costa and margins plane or moderately arching-recurved; margins plane, or recurved in lower half and plane above, or recurved at transition from base to acumen, entire; costa 30–50 µm wide near leaf base, in transverse section with dorsal stereid band, usually without ventral stereid band, or occasionally with few thick-walled cells venratally from guide cells; upper and median laminal cells 6–8(–10) µm, densely papillose, papillae C-shaped in larger cells or almost round in smaller cells; basal laminal cells rectangular, 30–45×10–15 µm, with length to width ratio 2–3(–4):1. Rhizoidal tubers 60–120 µm. Perichaetial leaves up to 2× 0.8 mm, with broad base more or less tightly appressed to seta, contracted to triangular-lanceolate acumen 0.2–0.5 of the basal part in length. Setae to 8 mm, reddish-yellow. Capsules 0.8–1.0× 0.3 mm. Opercula 0.6–0.8 mm long. Spores 11–14 µm.

Figures

Fig. 2. Habit of Streblotrichum species: J: S. jacuticum, OK3748 (J1–J3); EA: S. enderesii, Baumbartner, Exs. 293 of Barbula flavipes, Stiria (Austria) (EA1–EA3); ER: S. enderesii from Russia, OK3811 (ER1); OK3089 (ER2), OK3808 (ER3); T: S. taimyrense: type (T1–T2) and OK3872 (T3–T5); C: S. convolutum, OK3814 (C1–C2), OK3838 (C3–C4).

Fig. 3. A comparison of leaves, their transverse sections and basal cells of Streblotrichum species. J: S. jacuticum, OK3748; EA: S. enderesii, Baumbartner, Exs. 293 of Barbula flavipes, Stiria (Austria); ER: S. enderesii from Russia, OK3811 and OK3089; T: S. taimyrense, OK3872; C: S. convolutum, OK3838. Scale bars: 0.5 mm for leaves; 100 µm for basal leaf cells; 50 µm for leaf transverse sections.

Fig. 4. Leaf apices of Streblotrichum species. J: S. jacuticum, OK3748 (all); EA: S. enderesii, Baumbartner, Exs. 293 of Barbula flavipes, Stiria (Austria) (all); ER: S. enderesii from Russia, OK3811 (ER1); OK3089 (ER2), OK3089 (ER3), OK3626 (ER4), OK3089 (ER5); T: S. taimyrense, OK3872 (all); C: S. convolutum, OK3870 (C1–C2), OK3838 (C3–C5). Scale bar 50 µm for all except ER5 (25 µm).

Fig. 5. Rhizoidal tubers of Streblotrichum spe- cies: J: S. jacuticum, OK3748; EA: S. enderesii, Baumbartner, Exs. 293 of Barbula flavipes, Stiria (Austria); ER: S. enderesii from Russia, OK3811; T: S. taimyrense, OK3872; C: S. convolutum, OK3814. Scale bar: 50 µm for all, except N3 (100 µm).

Fig. 6. Capsules, setae and perichaetia of Streblotrichum species. J: S. jacuticum, OK3748; EA: S. enderesii, Baumbartner, Exs.293 of Barbulaflavipes,Stiria (Austria);ER:S.enderesiifromRussia,Perm Territory, 12.VIII.2005, Bezgodov 196, MHA9131969; T: S. taimyrense, OK3872; C: S. convolutum, OK3838. Scale bars: 1 mm for all.

Fig. 8. Streblotrichum enderesii (from: Russia, Perm Territory, Lysva Distr., Chusovaya River, 12.VIII.2005, Bezgodov 196, PPU, MHA9131869). A, C: leaf transverse sections; B: stem transverse section; D: mid-leaf cells; E: upper laminal cells; F, I: habit, dry; G: habit, wet; H: inner perichaetial leaf; J–K: outer perichaetial leaves; L–R: stem leaves; S: gemma; T: basal laminal cells. Scale bars: 5 mm for F; 2 mm for G, I; 1 mm for H, G–R; 50 µm for A–C, S; 100 µm for D–E, T.

Fig. 9. Streblotrichum taimyrense (from holotype). A: leaf transverse section; B: upper laminal cells; C–G: perichaetial leaves; H: subperichaetial leaf; I: mid-leaf cells; J: habit, dry; K–N, P–S: stem leaves; O: habit, wet; T: basal laminal cells. Scale bars: 2 mm for J, O; 1 mm for C–H, K–N, P–S; 100 µm for A–B, I, T.