Three New Species of Ferns (Pteridophyta) from Mesoamerica

In this research three new species of ferns of the Polypodiales Order are described: Ctenitis leonii A. Rojas, Elaphoglossum karinae A. Rojas and Pecluma celaquensis A. Rojas. Ctenitis leonii is characterized by its apical stipe scales marginally erose to ciliate, blade surfaces with two types of hairs present in both surfaces, ones 0.7 - 1.5 mm long and not glandular, the others 0.3 - 0.5 mm long and glandular and indusia are absent. Elaphoglossum karinae differs from Elaphoglossum dissitifrons Mickel by shorter rhizome, longer and relatively narrower rhizome scales, they lanceolate to linear-lanceolate and blackish costal scales. Pecluma celaquensis is similar to Polypodium martensii Mett., but differs by its thinner rhizome, smaller rhizome scales and these with a crown of brown cilia at the attaching point, relatively shorter stipe with longer hairs and these commonly no glandular, scaly rachis and it with longer and denser hairs, inframedial sori and glabrous sporangia.

Novelties in <i>Campyloneurum</i>(Polypodiaceae) from Mesoamerica

Three new species are described and another is recognized in Campyloneurum. Two species occur in Mexico to El Salvador and the others two are present in Nicaragua, Costa Rica and Panama. The new species are Campyloneurum acutum A. Rojas, C. leoniae A. Rojas and C. madrense A. Rojas. The first species differs from C. xalapense by broader rhizome scales, acute to attenuate blade apex, commonly two series of areoles between parallel veins, commonly one sori per areole and hydathodes absent or few evident. Campyloneurum leoniae differs from C. irregulare by more compact and non-pruinose rhizomes, thinner stipes, relatively broader, thinner and more opaque laminae, and distribution at lower elevations. Campyloneurum madrense is different to C. angustifolium because it has narrower and darker rhizome scales with denticulate margin, long scales cells and distributed at lower elevations. Finally, Campylonerum pittieri is here recognized as valid species and it differs from the similar C. amphostenon by longer rhizomes with appressed scales that have a patent, long acuminate apices, relative broader laminae, veins evident and distribution at higher elevations.

Irbesartan desmotropes:Solid-state characterization,thermodynamic study and dissolution properties

Irbesartan (IBS) is a tetrazole derivative and antihypertensive drug that has two interconvertible structures, 1H- and 2H-tautomers. The difference between them lies in the protonation of the tetrazole ring. In the solid-state, both tautomers can be isolated as crystal forms A (1H-tautomer) and B (2H-tautomer). Studies have reported that IBS is a polymorphic system and its forms A and B are related monotropically. These reports indicate form B as the most stable and less soluble form. Therefore, the goal of this contribution is to demonstrate through a complete solid-state characterization, thermodynamic study and dissolution properties that the IBS forms are desmotropes that are not related monotropically. However, the intention is also to call attention to the importance of conducting strict chemical and in solid-state quality controls on the IBS raw materials. Hence, powder X-ray diffraction (PXRD) and Raman spectroscopy (RS) at ambient and non-ambient conditions, differential scanning calorimetry (DSC), hot stage microscopy (HSM), Fourier transform infrared (FT-IR) and scanning electron microscopy (SEM) techniques were applied. Furthermore, intrinsic dissolution rate (IDR) and structural stability studies at 98% relative humidity (RH), 25℃ and 40 ℃ were conducted as well. The results show that in fact, form A is approximately four-fold more soluble than form B. In addition, both IBS forms are stable at ambient conditions. Nevertheless, structural and/or chemical instability was observed in form B at 40℃ and 98% RH. IBS has been confirmed as a desmotropic system rather than a polymorphic one. Consequently, forms A and B are not related monotropically.

Four New Species and Additional Distributions of <i>Elaphoglossum</i>Section <i>Elaphoglossum</i>(Dryopteridaceae) from the Neotropics

Four new species of Elaphoglossum sect. Elaphoglossum are described: E. Amparoanum A. Rojas, E. Chocoense A. Rojas, E. Fayorum A. Rojas and E. Luciae A. Rojas. The first species is related to E. Variolatum Mickel, but differs from it by having rhizome scales bicolorous and long ciliate margin. The second species is different to E. moranii Mickel by having narrower rhizome, shorter stipe, elliptic blade, attenuate blade base, shorter fertile fronds with blackish costa and present at lower altitudinal distribution. After that, the third species differs from E. lingua (C. Presl) Brack. by pale rhizome scales with long ciliate margin, shorter fronds and blade scales denser and lighter. Finally, the fourth species is related to E. atrosquamatum Mickel, but with relative longer fronds and broader blade. The geographical distributions of E. guatemalense (Klotzsch) T. Moore, E. longicrure Christ, E. minutum (Pohl ex Fée) T. Moore and E. nicaragüense A. Rojas are expanded.