Polevova S.V.1, Moiseenko A.V.2, Kolesnikova M.A.3, Ashikhmina D.A.1, Ignatov M.S.1,3 2019. An attempt to create air sacs in spores? On the unusual spore structure in moss Encalypta longicollis // Arctoa. Vol. 28: 171–178 [in English].
1 – Lomonosov Moscow State University, Faculty of Biology, Leninskie Gory Str. 1-12, Moscow 119234 Russia. E-mails: svetlanapolevova@mail.ru, ukiro23@yandex.ru
2 – Lomonosov Moscow State University, Laboratory of electron microscopy, Leninskie Gory Str. 1-32, Moscow 119234 Russia.
3 – Tsitsin Main Botanical Garden, Russian Academy of Sciences, Botanicheskaya Str., 4, Moscow 127276 Russia. E-mails: mary_co1840@mail.ru; misha_ignatov@list.ru
Keywords: bryophytes, evolution, haplolepideous, arthrodontous, spores
ABSTRACT. An empty perine processes covering spore surface are discovered in Encalypta longicollis, being likely the first known case of the gas-filled structures in moss spores. TEM images perform a diversity of variants of inner structure of these processes, showing likely a progressive decomposition of their inner material, from spongy to lacunose and finally resulting with a cavity in their middle up to half of their volume. The stages of decomposition correlate with the spreading of osmiophilous compound leaking from exine side, spreading in proximal part of perine layer diffusely, or more commonly along a flexuose channels that are terminated in areas where perine material shows maximal decomposition. The gas-filled space reduces the spore density, probably facilitating its ability for dispersal by water currents. This species is characterized by outstandingly large spores, 55–85(–95) mm in diameter, whereas in other species of the genus spores are 9–40(–50) mm.
doi 10.15298/arctoa.28.15