Pylaisia steerei (Ando & Higuchi) Ignatov, Arctoa

Ignatova, E. A., Kuznetsova, O. I., Shafigullina, N. R., Fedosov, V. E. & Ignatov, M. S., 2020, The genus Pylaisia (Pylaisiaceae, Bryophyta) in Russia, Arctoa 29 (1), pp. 135-178 : 152-154

publication ID

https://doi.org/10.15298/arctoa.29.11

persistent identifier

https://treatment.plazi.org/id/250E5054-FFED-FFA2-FCB6-B8FBFACDFEBD

treatment provided by

Felipe

scientific name

Pylaisia steerei (Ando & Higuchi) Ignatov, Arctoa
status

 

3. Pylaisia steerei (Ando & Higuchi) Ignatov, Arctoa View in CoL 10: 174. 2001. — Pylaisiella steerei Ando & Higuchi, Mem. New York Bot. Gard. 45: 211–215, f. 1–34. 1987.

Figs. 11–12 View Fig View Fig , 14F View Fig , 15 View Fig E-H, 34B.

Note on taxonomy. This species was described from Alaska ( Ando & Higuchi, 1987) by only one specimen, which was found very distinct from widespread P. polyantha in clearly falcate leaves. Later, plants with falcate leaves were found in Yakutia ( Ignatov et al., 2001), where they occur sporadically at places. Such plants grow at trunk bases in floodplains of creeks. Notably, the trees with such plants usually have an average-looking P. polyantha at 1.5 m above ground and higher. Preliminary tests confirmed the consistent ITS differences between such epiphytic and tree-base plants, e.g. confirming a specific status of P. steerei . Arikawa (2004) also accept- ed P. steerei , although discussing our Yakutian plants he commented that only some their traits agree with P. steerei . Also Arikawa referred to P. steerei a specemen collected in NW China, Xinjiang.

Present molecular phylogenetic analysis revealed two facts that make circumscription of P. steerei more complicated. First, most specimens of P. steerei by ITS and also IGS appeared to be indistinguishable from P. curviramea , a species distinct in its morphology. Second, Pylaisia species with falcate leaves appeared in at least three groups of haplotypes. One of them, strongly gifferentiat- ed genetically, is described below as a separate species, P. bezgodovii .

A rather substantial differentiation between two groups of haplotypes: (1) P. polyantha ‘ orientalis ’ and (2) group of haplotypes of P. steerei + P. curviramea poses a question on the delimitation of P. steerei and even its acceptance as a species. The strong reticulation in this group and variation in most characters mentioned as diagnostic for P. steerei force us to accept simply a pragmatic decision and refer to this species all specimens with strongly falcate leaves, excepting P. bezgodovii that possesses differential characters discussed below.

Description. Plants moderately small to medium sized, yellowish- or brownish-green. Stem and branches straight, moderately densely complanately foliate; leaves falcate secund, turned towards substrate. Stem leaves 1.1– 1.6× 0.4–0.6 mm, ovate-lanceolate, gradually narrowed to apex, usually boradly acuminate, slightly rounded to insertion; margins entire or serrulate above; median laminal cells 30–55×5–6 µm, alar cells subquadrate, rather few, forming slightly elongate triangular group 10–15 cells long and 5–10 cells wide. Branch leaves somewhat smaller. Capsules cylindrical, 1.5–2.0 mm long without operculum. Operculum conic to conic-rostrate. Peristome forming high conus when dry. Exostome teeth 300 µm long above the mouth, dorsal plates smooth below, and slightly papillose above; endostome to 350–380 µm above the mouth, not adherent to exostome, endostome segments narrow, not perforated along keel, strongly papillose. Spores 12–18 µm.

Distribution: Pylaisia steerei , as it is circumscribed here, occurs in Eurasia in Chukotka, Yakutia, Amurskaya Province, Khabarovsk Territory, Transbaikalia, Buryatia, Altai Republic and Xinjiang Province of China.

Specimens examined: RUSSIA: Chukotksky Autonomous District, Anadyr river, 20 Aug.1981 Afonina s.n. (LE); Republic of Buryatia: Kabansky Distr. , vicinity of settlement Rechka Vydrinaya, Fedosov et al.18-2-117 (MW9112045); Amurskaya Province : Norsky Reserve , valley of Nora River 1 km downstream cordon “Meunsky”, 9 Jul. 2010 Bezgodov 357 (MHA 9047656); Zeysky Reserve , Tukuringra Range, Garmakan River valley , Duduv & Kotelnikova 2013_Br_0027 (MW9061982); Altai Republic: Altaisky State Reserve , Chulyshman River valley , Berekhtuyaryk Creek , 26 Jun. 1989 Ignatov 0/1695 (MHA9130409); Republic of Sakha (Yakutia) :

Lensky Distr., mouth of Pilka River, 2 Aug. 1999 Ivanova s.n. (MW9061980); Tomponsky Distr., right bank of Kuraanakh River (ca. 30 km from Yakutsk-Magadan Hwy), Ignatov & Ignatova 17-186 (MHA9025955); Neryungri Distr., Chulma settl., 25 Jul. 1993 Ivanova s.n. (MHA9047655).

Kingdom

Plantae

Phylum

Bryophyta

Class

Bryopsida

Order

Hypnales

Family

Hypnaceae

Genus

Pylaisia

Loc

Pylaisia steerei (Ando & Higuchi) Ignatov, Arctoa

Ignatova, E. A., Kuznetsova, O. I., Shafigullina, N. R., Fedosov, V. E. & Ignatov, M. S. 2020
2020
Loc

Pylaisia steerei (Ando & Higuchi)

Ignatov 2001: 174
2001
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