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an Unusual Gentianella weigendii (Gentianaceae), New Gentian from Peru Volume Number 22, Pringle 1 2012 Gentianella (Gentianaceae) from Peru Habitat and phenology. Gentianella weigendii northern Ancash Department, seems likely that is it its known only from the type collection. It was found in total geographic range is not extensive, although well-developed jalca vegetation, among numerous according to Maximilian Weigend (pers. comm., 23 m shrubs and perennial herbs, 4000 Weigend June 2009), Gentianella weigendii was locally at et ( common The March al. 5083, in sched.). date of this collection at the type locality. on provides the only information available its named Etymology. Gentianella weigendii for is Maximilian Weigend, of the Institut fur Biologie- IUCN Red List category. Data are deficient for Systematische Botanik und Pflanzengeographie-der recommended listing (DD) (IUCN, 2001). With the Freien Universitat der Berlin, who collected the type species being known only from a single locality in specimen and thought that represented a new it Volume Number 22, Pringle 1 2012 Gentianella (Gentianaceae) from Peru coralline trichomes are absent; the corollas are green August Weberbauer, as well as herbarium specimens. and scarcely longer than the calyces; and the corolla If Weberbauer’s botanizing had extended to the range The lobes are ovate-triangular, shorter than the tube. of Gentianella weigendii, might be that Gilg’s it flowers of G. weigendii and G. thyrsoidea are similar description of the nectaries of Pitygentias was based in aspect, but in G. thyrsoidea the filaments are on alcohol-preserved flowers of G. weigendii, whereas equal, 5-8 mm, inserted the same level about the herbarium specimens that he identified as P. all at 10-60X 0.5X the height of the corolla tube. At pinifolia and P. thyrsoidea, and earlier as Gentiana magnification I detected no floral glands in G. tupa, represented Gentianella thyrsoidea. The name thyrsoidea Weigend 5125 and 7712, HAM), Gentiana tupa was based on plants from Diezmo, et al. ( SEM A BC but observations with fresh material and with Peru. Ruiz and Pavon specimen from Diezmo at would be desirable. (according to Ibanez, 2006), and a Ruiz and Pavon F MA) and (now and by Vegetatively, Gentianella weigendii thyrso- collection divided, interpreted G. 0.2- and Macbride an idea differ distinctly. Plants of G. thyrsoidea are Fabris (1958) (1959) as isotype of 3-6 name 3.5 dm; those of G. weigendii are dm. In G. the Gentiana pinifolia, were both designated by thrysoidea the basal and near-basal leaves are very the same unpublished name by Ruiz and Pavon in numerous, often over 100, and the cauline leaves are herb., and both were annotated as P. pinifolia by closely spaced the entire length of the stem (distal Gilg. These specimens are probably from a single intemodes commonly 2-8 mm, occasionally to 15 collection, of which identified a component as I mm mm, 40 on The The basionym rarely to the tallest plants). leaves Gentianella thyrsoidea. type of the BM) are ascending and distally incurved, and in combi- Gentiana thyrsoidea Hook. Cruikshanks s.n., ( name nation with the closely spaced axillary cymules, often likewise represents the species to which the much conceal of the stem. All of the leaves are Gentianella thyrsoidea currently applied. is Although weigendu the similarities of Gentianella of the abruptly expanded portion just above the basal to G. thyrsoidea and G. weberbaueri have been noted sheath, reminding Ruiz and Pavon of pine needles (as above, evidence, morphological or molecular, little indicated by the old epithet pinifolia The leaves are exists to indicate the phylogenetic relationships ). about eight per whorl the mid-cauline nodes, more among the South American species of Gentianella at numerous at the proximal nodes, with the bases or between the South American species and those of mm 8-12 which on united into a sheath, is the larger other continents. Divisions of Gentianella (historical- The plants. entire plant above ground forms a dense ly included in Gentiana into sections have included ) 2-6 cm cylinder in diam. In weigendii the basal species, or except magellanica (Gaudich.) G. all all G. X leaves are fewer and wider, 7-12 cm 4-13 mm; the Fabris ex D. M. Moore, in a single section, and X cm distal cauline leaves are lance-triangular, 2.5-7 divisions of Gentianella into segregate genera 7-13 mm; and the leaves are not expanded near the subsequent to Gilg’s recognition of Pitygentias have not discussed South American species. Some char- much and the leaves spread widely, so that of the acter states occur in diverse combinations rather than stem visible. The cauline leaves are in whorls of consistently occurring in syndromes, suggesting the is four, separate to the base. frequent occurrence of homeoplasy. Molecular phy- From which have Gilg’s description of Pitygentias Gilg, logenetic studies indicated that Gentianella, he segregated from South American Gentiana in s.l. & 1916, might be suspected that Gentianella with paired nectaries, monophyletic (Hagen it is weigendii had already been described, but no earlier Kadereit, 2001), but few South American species specific epithet is available for this species. Gilg have been included in such studies to date. treated Pitygentias as comprising two species, both of Weigend Weigend 5083, in sched.) et al. et al. ( now which are included in Gentianella thyrsoidea suggested that the flowers of Gentianella weigendii (Fabris, 1958). Although in 1916 Gilg described the might be cleistogamous. Self-pollination has been nectaries of Pitygentias as five calluses between the demonstrated in some Gentianaceae, including some adnate portions of the stamens, he included in P. high-altitude grassland species in South America & thyrsoidea (Hook.) Gilg plants that he (Gilg, 1896) (Freitas Sazima, 2009), but studies of pollination in had previously described as Gentiana tupa Gilg, in South American Gentianella have remained specula- which he had were engendered by said that the nectaries scarcely tive, despite the interest the diverse conspicuous. The material that he identified as P. floral morphology among these species. Gilg (1916) & pinifolia (Ruiz Pav. ex G. Don) Gilg in 1916 reported that the flowers of G. thyrsoidea (as included flowers preserved in alcohol, received from Pitygentias spp.) appeared to be cleistogamous, as