Tactics and life strategies of cenopopulation Hordeum brevisubulatum (Trin.) Link

Survival tactics and strategy of Hordeum brevisubulatum the dominant of meadow phytocenoses in CentralYakutia were studied. Traits-indicators annually change ontogenetic tactics, except for the taxonomic trait-indicator.Protective-stress and stress-protective ontogenetic strategy and CS type of ecological-coenotic strategin were established.

Is the presence of simple or glandular hairs a good trait for distinguishing species in Caryophyllaceae? A case study of Arenaria serpyllifolia sensu lato in southern Poland

The presence of different types of indumentum is regarded as a valuable taxonomic trait for describing and differentiating between species in many different families and genera. In Caryophyllaceae, however, this character is sometimes a subject of discussion and scientific conflicts. For instance, within <em>Arenaria serpyllifolia</em> sensu lato (s. l.), two or three taxa have been distinguished based on the presence or absence of glandular and/or eglandular hairs on the calyx and uppermost leaves, namely <em>A. serpyllifolia</em>, <em>A. viscida</em>, and <em>A. serpyllifolia</em> var. <em>intermedia</em>. The most common, based on material from Poland, is the glandular morphotype of <em>Arenaria serpyllifolia</em> s. l. (315 specimens), which is in contrast to the eglandular and intermediate morphotypes represented by 174 and 24 specimens, respectively; however, the ranges of distribution of these morphotypes fully overlap. Based on our macro- and micromorphological examination of specimens belonging to the group, as well as numerical and molecular studies, we conclude that the occurrence and abundance of eglandular and glandular hairs may vary in particular parts of specimens of <em>Arenaria serpyllifolia</em> s. l., i.e., on their calyces, bracts, and uppermost and middle cauline leaves. The width of the capsule was the only character for which significant differences between the SERP and VIS morphotypes were found; however, considering all studied morphotypes together, the capsule characters overlap considerably. Moreover, morphological variation expressed by different types of indumenta is not paralleled by internal transcribed spacer (ITS) polymorphism patterns. The probable lack of genetic barriers between populations of individuals with glandular or eglandular hairs supports the hypothesis that the type of indumentum is of minor taxonomic importance. However, it is possible that we are dealing with sampling in the hybrid zones of both taxa, and that individuals demonstrating morphological traits typical of both taxa (eglandular and glandular) do not in fact represent pure taxa but only different kinds of hybrids, backcrosses, or introgressive forms.

New Echiniscidae (Heterotardigrada) from Amber Mountain (Northern Madagascar)

A moss sample from the local biodiversity hotspot in lowland rainforest in the vicinity of Amber Mountain, Madagascar, yielded the discovery of twoEchiniscusC.A.S. Schultze, 1840 species, of which one is new to science.Echiniscussuccineussp. nov.is related to other members of thespinulosusgroup, but differs from them by the highly complicated structure of the dorsal plates, with intricately thickened parts of the armour forming ornamented pattern. The validity of the intraporal dark rings as a taxonomic trait is discussed in the context of the recovered intraspecific variability for the new taxon. Besides, rareEchiniscusafricanusMurray, 1907 is reported for the first time from the island.

Calcium Oxalate Cuticular Crystals in the Epidermis of Dracaena—A Taxonomic Feature of the Genus

The genus Dracaena has been placed in Agavaceae by most taxonomists. Recent work, however, has justified the placement in a separate family, Dracaenaceae. This study was initiated to examine the extracellular crystalline deposits in Dracaena and the possibility of this feature as a taxonomic trait of the genus. Fresh epidermal peels of five Dracaena species were observed under polarized light. Extracellular epidermal crystals were evident in all of them. The deposits were found between the cuticle and the outer primary epidermal cell wall. The crystal size varied from less than 1 μm to 5 μm along the long crystal axis. The size and quantity of the deposits varied between the species with largest and most numerous crystals in the cuticle of D. marginata and D. sanderiana. Dracaena deremensis, D. fragrans, and D. surculosa had smaller and less numerous crystals. The optical properties of the crystals were indicative of calcium oxalate monohydrate form which exhibited interference colors of second and third order. For comparison species of three members of Agavaceae were examined -Cordyline terminalis, Sansevieria trifasciata, and Yucca sp. No extracellular crystal deposits in the proximity of the epidermal wall were detected. Based on our observations, the genus Dracaena possessed an anatomical feature which could be used for identification. The existence of calcium oxalate crystals embedded in the cuticle was readily observable in fresh epidermal peels under polarized light.