Scapania apiculata Spruce.

Unan, Ayşe Dilek & Ören, Muhammet, 2021, New and noteworthy records of deadwood dwelling bryophyte species for Turkey and Southwest Asia, Cryptogamie, Bryologie 20 (4), pp. 33-44 : 37-38

3. Scapania apiculata Spruce.

( Fig. 4 )

Hepaticae Pyrenaicae: no. 15 (1847).

SPECIMEN EXAMINED. — Turkey. Kastamonu province, Azdavay district, around Zümrüt Village, 41°44’39”N, 033°13’44”E, on decayed undefined log, 1157 m. a.s.l., 28.VII.2016, Unan & Ören 102.4/A, ZNG.

ECOLOGY. — Scapania apiculata is acidophyte, hygrophyte, sciophyte, hemerophobic, and xylicolous species, which mainly colonize on decaying conifer logs that are periodically flooded with water (Dierssen 2001; Frey et al. 2006, Hassel et al. 2006; Casas et al. 2009, Naturvårdsverket 2014). This species is considered as a “poor competitor” and has a limited dispersal capacity ( Schuster 1974; Hallingbäck 1998; Hassel et al. 2006). Also S. apiculata is considered to be an indicator of old and natural boreal forests ( Borovichev & Shorohova 2019).

The Turkish specimen was collected on undefined, wet and naturally downed log that had decayed to stage 5 according to Ódor & Van Hees (2004), in a bank of a temporary stream in oriental beech and Trojan fir mixed forest. The dimensions of the log were 32 × 102 cm, and 60% of the visible surface was covered with the following bryophyte species (in alphabetical order): Blepharostoma trichophyllum (L.) Dumort., Brachytheciastrum velutinum (Hedw.) Ignatov & Huttunen var. velutinum , Brachythecium salebrosum (Hoffm. ex F.Weber & D.Mohr) Schimp. , Cephaloziella divaricata , Hypnum cupressiforme var. cupressiforme , Jamesoniella autumnalis (DC.) Steph. , Jungermannia leiantha Grolle , Lophocolea heterophylla , Lophozia ventricosa , Ptychostomum moravicum (Podp.) Ros & Mazimpaka , Rhizomnium punctatum and Sanionia uncinata (Hedw.) Loeske.

DISTRIBUTION. — Scapania apiculata has a scattered Holarctic distribution ( Düll 1983). This species has been recorded from various European countries, also from the Americas ( Canada, United States, and Venezuela), Asia ( China, Japan, and North Korea), and Russia ( Amakawa & Hattori 1953; Schuster 1974; Griffin 1975; Stotler & Crandall-Stotler 1977; Koponen et al. 1983; Tong & Yuhuan 1998; Hodgetts & Lockhart 2020). The Turkish record of this species is at southernmost limit of its Mediterranean and Western Asian distribution.

CONSERVATION. — Scapania apiculata is threatened in various IUCN categories in European countries (NT in Estonia; VU in Austria, Norway and Switzerland; EN in Sweden; CR in Bulgaria, Finland, and Poland; also Category 1 [Endangered] in Latvia) ( Hodgetts & Lockhart 2020). Studies have shown that the populations of this species is decreasing due to the human impact on their habitats in Nordic countries ( Hassel et al. 2006; Naturvårdsverket 2014; Hassel 2018). This species was found on only one log in the study area (approximately 45 000 km2); thus the area of occupancy (AOO) is less than 10 km 2. Due to its strict substrate selection, decreasing habitat and small AOO, S. apiculata may be classified as “CR” in Turkey according to the IUCN Criteria B2a ( IUCN 2019).

DESCRIPTION

Plants

Minute, yellowish green; shoots ascending to erect, 3.3-4.1 mm long and 1.1-1.6 mm wide.

Leaves

Transversely inserted, crowded at stem apex, imbricate, entire, acute, unequally bilobed; postical lobe 0.6-1.1 mm long and 0.3-0.4 mm wide; antical lobe 0.4-0.8 mm long and 0.2- 0.3 mm wide. Leaf cells large, isodiametric to longer than wide, 16-33 µm long and 14-22 µm wide in mid-leaf, trigones convex and conspicuous; marginal cells thin walled and not differentiated; cuticle slightly papillose. Oil bodies 2-6 per cell, spheric to ovoid, 4-10 µm long and 4-7 µm wide, not persistent.

Gemmae

Common, clustered on modified tips of reduced upper leaves, reddish brown, elliptical, single-celled, 9-15 µm long and 7-10 µm wide.

Perianths, sporophytes and male plants

Not recorded in the studied specimen.

Figures

FIG. 4. — Scapania apiculata Spruce: A, shoot; B, leaf; C, D, median leaf cells and oil-bodies; E, gemmae. Scale bars: A, 1 mm;B, 200 μm; C-E, 50 μm.