Demidova, E.E.1, Filin V.R.2 2001. Blepharoplast structure in Tayloria tenuis (Dicks.) Schimp. (Musci, Splachnaceae) // Arctoa. Vol. 10: 75–82 [in Russian].
1 Department of Biology, All-Russian Institute for Scientific and Technical Information (VINITI), Usievich St. 20, Moscow 125219, Russia
2 Biological Faculty, Moscow State University, Moscow 119234 Russia
KEYWORDS: mosses, blepharoplast, spermatogenesis, spermatid, anterior basal body, posterior basal body, microtubules.
ABSTRACT. The spermatid was studied at such developmental stage when the blepharoplast has been already formed but the transitional zones and flagella have not developed yet. Totally, over 150 sections of blepharoplasts from one antheridium were observed. On this basis an approximate reconstruction of the blepharoplast was undertaken. In all, the blepharoplast of Tayloria tenuis posesses a suit of morphological features common to most mosses but such an orientation of basal bodies (BBs) when the anterior basal body (ABB) slightly diverges posteriorly from the long axis of the spline and the posterior basal body (PBB) runs parallel to the spline axis. The ABB averages approximately 1.4 mm in length and is positioned approximately 0.1 μm from the anterior margin of the spline. The PBB measures approximately 4.8 μm in length; its proximal limit is situated approximately 0.1 μm from the spline anterior edge and approximately 0.1 μm from the level of the proximal limit of the ABB. The lamellar strip (LS) is characterized by a posterior taper from the right to the left. The length of LS in the middle is approximately 1.1 μm, the maximum width is approximately 0.4 μm. A closed aperture is located beneath the ABB on the right-hand side of the spline between the third and the fourth microtubules (MTs) from the right of spline margin. Its maximal width is two MT-diameter equivalents. The spline reaches a maximum width of 13 (occasionally 12 or 14) MTs in the region between the proximal limit of the PBB and the distal limit of the ABB. Behind this maximum, there is a step-wise deletion of MTs primarily along the right-hand edge of the spline, up to a total of 6 MTs at the level of the distal limit of the PBB. Comparison of blepharoplast morphology in Tayloria tenuis and that in a representative of the Funariaceae – Funaria hygrometrica studied by Carothers and Brown (1985) suggests that there are both similarities (spline MT number and LS size) and significant differences (spline aperture type, position of aperture, LS outline, orientation of BBs). These differences appear to be too important for considering the Splachnaceae and the Funariaceae be closely related.