197,543 research outputs found
Drosera quartzicola Rivadavia & Gonella 2011
No full text22. Drosera quartzicola Rivadavia & Gonella (2011: 34). Figures 6a,19d–f Type: — BRAZIL. Minas Gerais: Santana do Riacho, km 112-113 da estrada para Conceição do Mato Dentro (MG-10), em morro após bifurcação da trilha para o Travessão e cachoeira Congonhas, seguindo à esquerda, 1360 m, 19 April 2010, Gonella et al. 264 (holotype SPF-203300!). Perennial, rosetted, acaulescent or forming short columns up to 40 mm tall. Glandular trichomes of TSG type present on both leaf surfaces, scapes, pedicels and sepals. Leaves semi-erect, with circinate vernation, lanceolate, petioles about as long and as wide as the lamina and lacking eglandular trichomes in the adaxial surface, abaxial leaf surface densely eglandular-pilose; stipules triangular, 6–8 mm long, golden-brown. Scapes short, base erect, 17–115 mm long; petals pink; gynoecium 3-carpelate, styles bifurcated at the base. Seeds narrowly oblong-ovate, 0.7–0.8 mm long, testa reticulate, black (based on Rivadavia & Gonella 2011). Illustrations: — Rivadavia & Gonella (2011: 35, fig. 1—habit and details). Distribution: — Brazil (Southeast: MG), endemic to the central portion of Serra do Cipó, in central Minas Gerais (Fig. 6a). Habitat: —Relatively dry areas of campo rupestre vegetation, in fine silica sand mixed with white quartz gravel. Found at elevations between 1100–1360 m. Phenology:— Found in flower from November to April. Conservation status: —Critically Endangered (CR) B1ab(iii, iv). Rivadavia & Gonella (2011) designated this species as CR based on its restricted occurrence, fragile habitat, and small number of sub-populations. Only four subpopulations were known at the time of publication (containing 20, 60, 100, and 120 individuals respectively; Rivadavia & Gonella 2011), with two additional having been discovered since, both with ca. 20 adult individuals. This brings the total known population size of D. quartzicola to ca. 340 individuals. Despite the discovery of new populations, the species remains very restricted (EOO= 9.1 km 2, AOO= 12 km 2), with each population containing a reduced number of individuals spread over a very limited area of a few m 2 each, making them very susceptible to stochastic events. The species is further threatened by drastic reduction of habitat quality due to anthropogenic fires, invasive grasses, and climate change. Of the six known populations, two are found inside the Serra do Cipó National Park, and the remaining four in the Environmental Protection Area (APA) Morro da Pedreira. Notes: — Drosera quartzicola is most similar to D. chrysolepis, with which it is syntopic at one location where infrequent hybrids are also found (see ‘Natural Hybrids’ below; Rivadavia & Gonella 2011). It can be distinguished by the acaulescent or column-forming habit (Fig. 19d, e; vs. caulescent), petioles about as wide as the lamina (Fig. 19e; vs. petiole 2-3 times narrower than the lamina), and shorter inflorescences (Fig. 19d). Specimens examined: —For an extensive listing, see Rivadavia & Gonella (2011: 39). Additional specimens examined: — BRAZIL. Minas Gerais: Santana do Riacho, Serra do Cipó, km 114 da MG-10, trilha para o Canyon do Travessão, 10 November 2013, Gonella et al. 633 (SPF, BHCB, RB); APA Morro da Pedreira, km 110 da MG-10, 06 July 2014, Gonella & Rohrbacher 669 (SPF), 670 (SPF).Published as part of Gonella, Paulo Minatel, Sano, Paulo Takeo, Rivadavia, Fernando & Fleischmann, Andreas, 2022, A synopsis of the genus Drosera (Droseraceae) in Brazil, pp. 1-76 in Phytotaxa 553 (1) on pages 53-54, DOI: 10.11646/phytotaxa.553.1.1, http://zenodo.org/record/679668
Funciones de los síndicos y fiscalización oficial de las sociedades
No full textFil: Gonella, Eduardo M.. Universidad de Buenos Aires. Facultad de Ciencias Económicas. Buenos Aires, Argentina
Begonia piranga L. Kollmann & Gonella 2021, sp. nov.
No full text<i>Begonia piranga</i> L. Kollmann & Gonella, <i>sp. nov.</i> (Figs. 1, 2, 3). <p> <i>Begonia piranga</i> is closely related to <i>Begonia ruhlandiana</i> Irmscher (1953: 67) with which it shares stellate trichomes, craspedodromous venation, deciduous stipules and bracts, pistillate flowers with prophylls and ovary with one placenta per locule. However, <i>B. piranga</i> is easily distinguished by having red flowers (<i>vs</i>. white to pink); staminate flowers with abaxially densely pilose sepals (<i>vs</i>. glabrescent), ovate sepals, 0.75–1.05 × 0.6–0.9 cm (<i>vs</i>. orbiculate sepals, 0.5–0.7 × 0.47–0.6 cm), petals 2 (<i>vs</i>. petals absent); pistillate flowers with a pilose ovary (<i>vs</i>. glabrescent); capsules 0.9–1 × 0.3–0.4 cm (<i>vs</i>. ca. 0.5 × 0.3–0.4 cm), and fruit wings 6–12 mm wide (<i>vs</i>. 1–4 mm).</p> <p> <b>Holotype</b>:— BRAZIL. Minas Gerais: Conselheiro Pena, Serra do Padre Ângelo, Pico do Padre Ângelo, no platô do topo do pico, campo rupestre, 19°19’12.78”S 41°34’42.02”W, 1500 m, 30 November 2020, <i>P. M. Gonella & D. P. Cordeiro 1824</i> (MBML).</p> <p> <b>Description</b>:—Perennial subshrub, erect, up to 1.5 m tall, pilose, densely lanate to lanuginose; indumentum consisting of stellate trichomes, 4–6 branched at the apex, ferruginous when fresh and white when mature, present on stem, leaves, and inflorescence parts. <i>Stems</i> 0.45–0.75 cm diam., internodes 0.4–5.6 cm long, green to red, brown when mature, densely pilose. <i>Stipules</i> lanceolate, 1–1.5 × 0.4–0.7 cm, red, apex acute, margins entire, deciduous, adaxial surface glabrous, densely pilose on the abaxial surface. <i>Petioles</i> 1.2–1.3 cm long, red, densely pilose. <i>Leaf blades</i> ovate, 5.8–6.5 × 3.5–4.3 cm, conduplicate, succulent, chartaceous when dry, adaxial surface green, shiny, glabrescent, abaxial surface densely pilose, apex obtuse, base oblique, margin entire, hydathodes present, venation craspedodromous. <i>Inflorescences</i> 19–63 cm long, 3–4 dichasial cymes, red, densely pilose. <i>Bracts</i> elliptic, 0.7–2 × 0.9– 0.2 cm, reddish, deciduous, apex acute, densely pilose on the abaxial surface, carinate. <i>Staminate flowers</i>: pedicel 3–4 mm long, red, densely pilose; sepals 2, ovate to elliptic, 0.75–1.05 × 0.6–0.9 cm, cinnabar red, apex obtuse, margins entire, densely pilose on the abaxial surface; petals 2, obovate to elliptic, 0.5–0.83 × 0.2–0.5 cm, red carmine, apex obtuse, margins entire, slightly pilose on the abaxial surface; stamens ca. 20, ca. 2 mm long, yellow, filaments subequal, ca. 0.7 mm long, anthers ca. 1.3 mm, rimose, ovate, connective slightly projecting, apex rounded. <i>Pistillate flowers</i>: pedicels ca. 0.7 cm long, red, densely pilose; prophylls (1–)2, elliptical to ovate, 0.6–0.75 × 0.35–0.5 cm, persistent, at the base of the ovary, apex obtuse to acute, densely pilose on the abaxial surface; sepals 2, elliptical, 0.6–1.2 × 0.4–0.9 cm, carmine red to magenta, apex obtuse, densely pilose on the abaxial surface; petals 3, elliptical to oblanceolate, 3.2–8 × 3–4.5 mm, carmine to pink-whitish, apex obtuse to rounded, slightly pilose on the abaxial surface; ovary 3-locular, placentation axile, one placenta per locule, apex of the placenta slightly divided; styles 3, ca. 3 mm long, yellow, united at base, each bifurcate, entirely covered with stigmatic papillae. <i>Capsule</i> 0.9–1 × 0.3–0.4 cm, basally dehiscent, covered by trichomes, peduncles 0.8–1 cm long, covered by trichomes, <i>wings</i> 3, unequal, covered by trichomes, the largest one ca. 1.6–1.7 × 0.7–1.2 cm, slightly ascendant to straight, apex rounded to acute, the two smallest ones 0.7–1.2 × 0.6–1 cm, descendant, apex rounded. <i>Seeds</i> ca. 0.25–0.35 × 0.2 mm, oblong, apex rounded.</p> <p> <b>Additional specimens examined (paratypes)</b>:— BRAZIL. Minas Gerais: Conselheiro Pena: Serra do Padre Ângelo, Pico do Padre Ângelo, no platô do topo do pico, campo rupestre, 19°19’6.9”S 41°34’43.8”W, 1500 m, 04 December 2018, <i>P. M</i> <i>. Gonella, A. Fleischmann, L. Medeiros & L.</i> <i>França 1087</i> (MBML); <i>ibid</i>, 21 August 2020, <i>P. M</i> <i>. Gonella, E. Ramos, D. P. Cordeiro, T. H. Condez & P. R.</i> <i>Bartholomay 1542</i> (MBML, RB).</p> <p> <b>Distribution and habitat:</b> — <i>Begonia piranga</i> is endemic to Pico do Padre Ângelo, the second highest peak of Serra do Padre Ângelo (Conselheiro Pena, Minas Gerais), where it can be found on the top plateau at elevations around 1500 m (Fig. 1). The species grows in <i>campos rupestres</i>, being found on pockets of sandy soil accumulated between large quartzitic rocks, on sites exposed to direct sunlight (Fig. 2A–C). Only around 20 individuals of the species have been located in the area so far, all growing within a radius of 100 m.</p> <p> <b>Phenology</b>:—The species was observed with flowers in February, May, and from August to December, suggesting a continuous flowering period.</p> <p> <b>Conservation status assessment</b>:—Critically Endangered CR B2ab(iii) + D. <i>Begonia piranga</i> has an AOO of 4 km 2 (criterion B2), is known from a single location (sub-criterion B2a), with approximately twenty mature individuals (criterion D). This species is subject to several threats such as invasive species, wildfires, climate change, and unregulated tourism that can lead to poaching and aggravation of invasion by alien species, all of which leading to a decline in habitat quality (sub-criterion B2b(iii)). The threats to which the species is subject are thoroughly described for other endemic species of the area in Gonella <i>et al.</i> (2015), Andrino & Gonella (2021), and Antar <i>et al.</i> (2021a, 2021b). The Serra do Padre Ângelo and other areas of <i>campos rupestres</i> of the João Pinto Formation remain as some of the few natural areas in the region, which had most of its original vegetation converted into pastures (Fig. 1). The recent wildfire of great proportions that affected the Serra in late September 2020 (see Andrino & Gonella 2021) also impacted this species, with at least two of the monitored individuals having disappeared after the fire. Large areas of the top plateau of Pico do Padre Ângelo that remained unexplored before the fire could also have harbored individuals of this species. Therefore, its conservation status is further aggravated by the extremely reduced population size, now estimated to be less than 20 known mature individuals. Based on its restricted occurrence, reduced population size, listed threats to which it is exposed which are leading to a decline in the quality of its habitat, and the fact that it is not found inside any protected area, <i>B. piranga</i> is provisionally assessed as Critically Endangered under the aforementioned IUCN Red List criteria (IUCN 2012).</p> <p> <b>Etymology</b>:—The red and showy flowers of this species are one of its most distinctive characters (Fig. 2G–I), hence we have chosen the epithet “ <i>piranga</i> ”, which means “red” in the Tupi-Guarani language (Bueno 2008).</p> <p> <b>Notes</b>:—According to the sectional classification of Doorenbos <i>et al.</i> (1998), <i>B. piranga</i> belongs to <i>B.</i> sect. <i>Pritzelia</i>, a section with approximately 150 species from South America, characterized by the entire placentae and presence of cystoliths in the leaf cells (Doorenbos <i>et al</i>. 1998).According to the sectional classification of Moonlight <i>et al.</i> (2018), <i>B. piranga</i> belongs to <i>B.</i> sect <i>Tetrachia,</i> a section with approximately 16 species from Brazil, characterized by the presence of stellate or peltate, scale-like hairs; frequently peltate leaves; axile, usually simple placentation; and cymose inflorescences.</p>Published as part of <i>Kollmann, Ludovic Jean Charles & Gonella, Paulo Minatel, 2021, Novelties in Begonia (Begoniaceae) from the campos rupestres of Serra do Padre Ângelo, Minas Gerais, Brazil: a new species and a new record, pp. 69-77 in Phytotaxa 510 (1)</i> on pages 70-74, DOI: 10.11646/phytotaxa.510.1.7, <a href="http://zenodo.org/record/5426303">http://zenodo.org/record/5426303</a>
Guido Gonella. L'uomo, il cristiano, la città.
No full textSi contestualizzza la figura di Gonella nell'ambiente della città di Verona, con attenzione specailmente alle numerose istituzioni educative, specie quelle relative al 1800 e 1900. Si segue la sua carriera scolastica fino alla prima laurea in Filosofia presso l'Università Cattolica ed alla seconda in Legge conseguita presso l'Università di Roma. Ci si sofferma sull'attività associativa e pubblicistica svolta presso la FUCI e poi con i laureati cattolici dell'amico Igino Righetti e di mons. Montini. Particolare attenzione viene rivolta alla rubrica "Acta Diurna" da lui curata per vari anni per l'Osservatore Romano. Segue il breve periodo di carcere che blocca comunque la carriera universitaria e lo lega a personaggi di livello nazionaler ma anche locale della lotta di Resistenza al Fascismo. Non mancano vari riferimenti alle vicende della famiglia d'origine e della famiglia da lui formata
Investigaciones de seminariov.3
No full textFil: Gonella, Eduardo M.. Universidad de Buenos Aires. Facultad de Ciencias Económica
Investigaciones de seminariov.4
No full textFil: Gonella, Eduardo M.. Universidad de Buenos Aires. Facultad de Ciencias Económica
Stigmatodon enigmaticus D. R. Couto, Gonella & A. F. Costa 2023, sp. nov.
No full textStigmatodon enigmaticus D.R. Couto, Gonella & A.F. Costa, sp. nov. (Figures 1–2) Stigmatodon enigmaticus differs from S. vexatus by the more numerous leaves (15–25 vs. 10–12 in number), distinctly smaller leaf blade (6–8.5 × 1.5–2.3 cm vs. 13–14 × 2.8–3.7 cm), with acuminate apex (vs. caudate), floral bracts red (vs. green), flowers with diurnal anthesis (vs. nocturnal), greenish-yellow sepals (vs. green), yellow petals (vs. greenish-yellow), and stamens and stigma exceeding the corolla (vs. shorter than the corolla). Type: — BRAZIL. Minas Gerais: Conselheiro Pena, Serra do Padre Ângelo, Serra do Pinh „o, campo rupestre, 1,300 m elevation, 2 May 2021 (flowered in cultivation in November 2021), P . M. Gonella 2965, D. P. Cordeiro, G. A. da Silva, P. R. Bartholomay, J. C. Ribeiro & L. Medeiros (holotype MBML!). Description: — Plant rupicolous, heliophytic, 21–35.5 cm tall when flowering, propagating by basal axillary shoots. Leaves 15–25, forming a utriculiform rosette; sheath ovate to elliptic, 6–8.5 × 4–5.5 cm, purplish to purplishgreen distally, castaneous at the base, densely lepidote on both sides, chartaceous; blade narrowly triangular, 6–8.5 cm long, 1.5–2.3 cm wide at the base, green to dark reddish, densely lepidote on both sides, forming white crossbands on adaxial surface, suberect to spreading-recurved, revolute along the margins (under water stress), apex acuminate. Peduncle suberect or curved at the base, (16-) 23–30 cm long, 1.2–1.8 mm in diameter, green, glabrous; peduncle bracts erect, exceeding the internodes, imbricate, elliptic, apex rounded then acuminate to caudate, 1.7–3 × 1.4 cm, the lower ones subfoliaceous, green, the upper ones red, lepidote on both sides, more sparsely lepidote near the margins, densely white lepidote near the apex. Inflorescence simple, 4–12 cm long, suberect, with apical sterile bracts, 3–7 flowered; main axis slightly geniculate, 2.8–3 mm in diameter, green, glabrous, internodes 5–9(-16) mm; floral bracts suborbicular, apex broadly obtuse, 1.7–2.2 × 1.0– 1.7 cm, ecarinate, secund with the flowers at anthesis, red, exceeded by the sepals, densely lepidote abaxially, adaxially glabrous, coriaceous. Flowers distichous, secund at anthesis, diurnal, 4.0– 5.5 cm long; pedicel green, 4.5–7.2 mm long; sepals elliptic, apex obtuse, 20–23 × 10–11 mm, greenishyellow, ecarinate, glabrous, coriaceous, free; petals linear-oblong, 3.0–3.5 × 0.5–0.8 cm, apex rounded to emarginate, suberect with spreading apex, yellow, glabrous, connate at the base to 0.9–1.5 mm, forming a prevailing tubular corolla; petal appendages 6–7.6 × 2–2.5 mm, spatulate, apex rounded, distally free for 2.5–3.2 mm; stamens exserted for 2–3.8 mm; anthers oblong in outline, 4–5 mm long, obtuse, dorsifixed near the base; filaments complanate, 25–31 mm long, pale yellow, adnate to the petals for 4.3–5 mm; ovary superior, 4.2–5.4 mm long; style 30–35 mm long; stigma convolute blade type (the vriseoid type II), exceeding the corolla for 8–9 mm, green, ca. 1.4 mm in diameter. Capsules unknown. Phenology: —Colected with flowers in October (in situ), and in November and December (in cultivation). Distribution and ecology: — Stigmatodon enigmaticus is a lithophyte on quartzitic rocky outcrops (Fig. 1C) within the Atlantic Forest, in the municipality of Conselheiro Pena, eastern Minas Gerais state, Brazil. So far, the species is only known from the type locality at Serra do Pinh„o (above 1,250 m elevation), part of Serra do Padre Ângelo (Fig. 1A). At the type locality, the species forms a small and sparse population, exposed to full sunlight, growing in crevices or fissures, or directly on bare rock, usually on horizontal or inclined quartzitic rocky outcrops (Fig. 1), surrounded by herbaceous and shrubby vegetation (Fig. 1B, C). The floral characteristics of this species, i.e., floral bracts red, flowers with diurnal anthesis, yellow petals, and stamens and stigma exceeding the corolla (Fig. 1F–H), allows us to suggest that it is possibly pollinated by hummingbirds (Neves et al. 2020), an unusual characteristic for the genus Stigmatodon (its species have nocturnal flowers and bat-pollination). This observation raises new and promising perspectives for evolutionary, morphological, and taxonomic studies in Stigmatodon. Preliminary conservation status: —Critically Endangered (CR): B2ab(iii). Stigmatodon enigmaticus is a microendemic species with an Area of Occupancy (AOO) of 4 km ², found only in Serra do Pinh„o (Fig. 1 A–B). While the rock outcrop where it is found is relatively protected from fires by the irregular topography, the surroundings have been severely transformed in the past decades, from the original matrix of Semideciduous Seasonal Forest to pastures for cattle farming. Fires for pasture renovation are regular in the area, as is the active conversion of the few remnants of secondary forest into pastures, with the use of fire, one of such observed during one of the expeditions to the area in October 2022. Similar criminal fires resulted in a wildfire of great proportions that affected the neighboring Pico do Padre Ângelo in September 2020, affecting many of its endemics (Andrino & Gonella 2021, Kollmann & Gonella 2021, Gonella et al. 2022). The frequent fires in the area facilitated the invasion of the rocky outcrops by alien grass species, such as Melinis minutiflora Beauvois (1812: 54), which can be found on the rocky outcrop that S. enigmaticus inhabits. The area where the species is found is not protected by any sort of Protected Area but should be recognized as a priority for conservation given the exceptional biodiversity and the relevance of the ecosystem services provided by the mountainous relief and native vegetation of Serra do Padre Ângelo, such as water cycle, climate balance, and pollinators, among others. Finally, less than 20 mature individuals could be located in the area, suggesting that the population is relatively small, as is common with microendemic species from the Campos Rupestres (Conceiç„o et al. 2007). Given the aforementioned characteristics and threats, we have preliminarily assessed S. enigmaticus as Critically Endangered based on the categories and criteria of IUCN (2012). Etymology: — This new species was discovered in May 2021, when only sterile specimens were observed, and its vegetative characteristics pointed to Stigmatodon. However, when in flower, its red bracts and yellow sepals and petals, common in Vriesea and so far not reported for Stigmatodon, raised the question of its generic placement. This puzzling combination inspired the epithet, from the Greek aenigma meaning “riddle”, or “enigma”. Additional specimens examined (paratypes): ___ BRAZIL. Minas Gerais: Conselheiro Pena, Serra do Padre Ângelo, Serra do Sossego, campo rupestre, 1,250 m elevation, 15 October 2022, (fl.), D. R . Couto 6625, P. M. Gonella, L. Medeiros, D. Cordeiro & L. Magalhães (R!); ibidem, 1,350 m elevation, 13 May 2022, P . M. Gonella 3521, E. P. Fernandez, G. Crispin, G. A. Queiroz & J. C. Ribeiro (MBML!). Discussion: — Stigmatodon enigmaticus, resembles the small rupicolous species of “ Stigmatodon limae group” (Fig. 1 C), from which it is easily distinguished by its red floral bracts, as well as by the yellow and linear-oblong petals, and the exserted stamens and stigma. Among the species of the S. limae group, this new species is morphologically most similar to S. vexatus, which is endemic to the Pico da Aliança, an emblematic quartzitic mountain distant about 20 km from the type locality of S. enigmaticus, in the neigboring municipality of Alvarenga. Stigmatodon enigmaticus can be distinguished from S. vexatus by its ovate to elliptic leaf sheaths (vs. broadly ovate), which are purplish to purplish-green toward the apex and castaneous at the base (vs. vinaceous brown adaxially), leaf blade with revolute margins (under water stress vs. flat to involute), peduncle longer (up to 30 cm vs. up to 13 cm), larger flowers (4.0– 5.5 cm vs. ca. 3.2 cm), and obovate to elliptic sepals (vs. oblong-elliptic; data on S. vexatus from Leme 2016). For the Stigmatodon limae group, three stigma types have been recognized recently (see Leme et al. 2022a), which are relevant to the Stigmatodon taxonomy: tubo-laciniate type II, observed in S. rosulatulus (Leme 2012: 10) Leme, G.K. Br. & Barfuss (in Barfuss et al. 2016: 58) and S. ilhanus Leme & D.R. Couto (in Leme et al. 2022a: 7); (ii) convolute-blade (the vriseoid type II), observed in S. freicanecanus (Siqueira & Leme, 2006a: 377) D.R.Couto & A.F.Costa (in Couto et al. 2022: 352), S. oliganthus (Baker, 1887: 345) D.R.Couto & A.F.Costa (in Couto et al. 2022: 354), S. vellozicolus (Leme & Siqueira 2006b: 406) D.R.Couto & A.F.Costa (in Couto et al. 2022: 354), S. vexatus and S. enigmaticus; and (iii) convolute-blade type III (stigmadontoid type III), observed in S. andaraiensis (Leme 2012: 16) D.R.Couto & A.F.Costa (in Couto et al. 2022: 352), S. itamarajuensis Leme, D.R. Couto & L. Kollmann (in Leme et al. 2022a: 9), S. limae (Smith 1970: 181) D.R.Couto & A.F.Costa (in Couto et al. 2022: 354), and S. zonatus (Siqueira & Leme 2006a: 374) D.R.Couto & A.F.Costa (in Couto et al. 2022: 354). The floral features of S. enigmaticus, i.e., red bracts and yellow perianth, exserted stamens and stigma, and diurnal anthesis, are unique in the genus Stigmatodon but common in Vriesea (Costa et al. 2014, Neves et al. 2020, Couto et al. 2022). These characteristics, associated with hummingbird pollination syndrome (ornithophily), seem to be the ancestral state among bromeliads, while bat pollination (chiropterophily) originated multiple times in the family as a whole (Aguillar-Rodríguez et al. 2019), as well as in Vriesea (Kessler et al. 2020; Neves et al. 2020), and is supported as an ancestral state in Stigmatodon species (Couto et al. 2022). All the 33 previously known species of Stigmatodon bear chiropterophilous flowers, therefore the floral features of S. enigmaticus could result from the retention of the ancestral state or a reversion to it, a hypothesis that needs to be tested with molecular phylogeny.Published as part of Couto, Dayvid R., Gonella, Paulo M. & Costa, Andrea F., 2023, Stigmatodon enigmaticus (Bromeliaceae, Tillandsioideae), a new lithophytic species from the Campos Rupestres within the Brazilian Atlantic Forest, pp. 207-215 in Phytotaxa 584 (3) on pages 209-212, DOI: 10.11646/phytotaxa.584.3.7, http://zenodo.org/record/764569
Investigaciones de seminariov.2
No full textFil: Gonella, Eduardo M.. Universidad de Buenos Aires. Facultad de Ciencias Económica
Search for heavy Majorana or Dirac neutrinos and right-handed W gauge bosons in final states with charged leptons and jets in pp collisions at TeV with the ATLAS detector
No full textA search for heavy right-handed Majorana or Dirac neutrinos NR and heavy right-handed gauge bosons WR is performed in events with energetic electrons or muons, with the same or opposite electric charge, and energetic jets. The search is carried out separately for topologies of clearly separated final-state products ('resolved' channel) and topologies with boosted final states with hadronic and/or leptonic products partially overlapping and reconstructed as a large-radius jet ('boosted' channel). The events are selected from pp collision data at the LHC with an integrated luminosity of 139 fb - 1 collected by the ATLAS detector at s=13 TeV. No significant deviations from the Standard Model predictions are observed. The results are interpreted within the theoretical framework of a left-right symmetric model, and lower limits are set on masses in the heavy right-handed WR boson and NR plane. The excluded region extends to about m(WR) = 6.4 TeV for both Majorana and Dirac NR neutrinos at m(NR) < 1 TeV. NR with masses of less than 3.5 (3.6) TeV are excluded in the electron (muon) channel at m(WR) = 4.8 TeV for the Majorana neutrinos, and limits of m(NR) up to 3.6 TeV for m(WR) = 5.2 (5.0) TeV in the electron (muon) channel are set for the Dirac neutrinos. These constitute the most stringent exclusion limits to date for the model considered. © 2023, The Author(s)
Drosera magnifica Rivadavia & Gonella, sp. nov.
No full textDrosera magnifica Rivadavia & Gonella, sp. nov. (Figs. 1–4) Type: — BRAZIL. Minas Gerais: Conselheiro Pena, Pico do Padre Ângelo, 1530 m, 28 November 2013, Gonella & Rivadavia 645 (holotype SPF!, isotypes BHCB!, MO!, P!, RB!, SPF!). Diagnosis: — Drosera magnifica differs from D. graminifolia and D. spiralis by the long prostrate or ascending stems up to 123.5 cm long; by the higher number of active leaves per rosette, which are sessile and broader linear-lanceolate in shape, 100–240 × 3–8 mm, with circinate-involute vernation (lateral margins of lamina involute in bud), entirely lacking glandular trichomes, with a raised midrib on the adaxial surface extending from base to ⅓–½ of the leaf length, the adaxial surface with a short, triangular to narrowly triangular tentacle-free zone at the base that is eglandularpilose, and the mature leaves with revolute margins; by multiple-branched inflorescences (branched scorpioid cymes), covered with stalked glandular trichomes 0.1–0.4 (– 0.5) mm long; and by the larger fusiform seeds 1–1.2 mm long. Description: — Perennial rosetted herbs, caulescent; stem well-developed, up to 123.5 cm long, prostrate or ascending (supported by surrounding vegetation), often apically branching once and with basal sprouts, covered by the persistent dead leaves (70–100 mm between inflorescences from different years). Roots succulent, black, sparsely branched, densely covered by root hairs. Indumentum consisting of white (drying gold colored) eglandular trichomes up to 4 mm long, occurring on the base of the adaxial leaf surface, whole abaxial leaf surface, scape, bracts, pedicels and sepals; stalked glandular capitate trichomes 0.1–0.4 (– 0.5) mm long on scapes, bracts, pedicels and sepals; minute sessile glands ca. 0.03 mm in diameter on both leaf surfaces, scapes, bracts, pedicels and sepals. Leaves 100–240 × 3–8 mm, active leaves 7–18 per rosette, linear-lanceolate, apex acute, vernation circinate-involute (regular or irregular), lamina of mature leaves with revolute margins, green in color, erect to semi-erect, with a raised midrib on adaxial surface extending from base to approximately ⅓–½ of length (less conspicuous in dried specimens), leaves becoming reflexed and drying curled when old; petioles absent in mature plants (leaves sessile), but often distinct in juvenile plantlets; lamina comprising the entire leaf length, with the abaxial surface densely eglandular-pubescent, especially towards the margins, and covered with numerous sessile glands, while the adaxial surface is covered with numerous sessile glands and red, carnivorous, capitate tentacles with radial symmetric gland heads, except for a triangular to narrowly-triangular tentacle-free zone of 7–45 × 2–7 mm at the base, which is densely to sparsely eglandular-pilose, but glabrous at the very base; stipules 8–15 mm long, 3.5 –9.0 mm wide at the base, triangular, membranaceous, translucent bronze-gold in color (sometimes whitish to reddish), apex acute and fimbriate. Scapes 1 per plant (in plants with forked stems, one scape per rosette), terete, hollow, base erect and 2–5 mm in diameter, 165–350 mm in total length (including floriferous part; the peduncle 120–225 mm long), densely pilose, covered with glandular and eglandular trichomes, the indumentum becoming denser towards the apex; inflorescence in a multiple-branched scorpioid cyme, with (2 –) 6–10 (– 14) branches, green to reddish-green in color, bearing 17–190 flowers, often with 1–4 larger bracts not supporting a flower at the base of the rachis (“sterile bracts”), 7–12 mm long, linear; floral bracts caducous, 4–6 mm long, linear-lanceolate to ovate, usually absent, densely glandular and eglandular-pilose on the abaxial surface; pedicels 2.5 –7.0 mm long, inserted 2–7 mm apart from each other, densely glandular and eglandularpilose; sepals 5, pinkish-red when in bud and during anthesis, greenish when in fruit, 4.5 –8.0 mm long, 2.2 –3.0 mm wide, oblong-obovate to ovate, united at basal 1 / 4 – 1 / 5 of length, densely glandular-pilose and sparsely eglandularpilose, apex rounded to broadly acute; petals 5, 8– 10 mm long, 6–8 mm wide, obovate, light pink; stamens 5, ca. 3.5 mm long, filaments white, anthers 1.5–1.8 mm long, bithecate, yellow; ovary 1.2–1.5 mm in diameter at anthesis, 3 - carpellate, globose, rounded in outline, green; styles 3, forked at the base, 4.0– 4.8 mm long including stigmas, stigmas simple or bilobed, pinkish-white in color; fruit a dry capsule, 1.5–2.5 mm long, globose, 3 -valvate. Seeds fusiform, 1.0– 1.2 × 0.2–0.3 mm, testa reticulate, dark brown. Etymology: —The epithet “ magnifica ” refers to the magnificent appearance of this new species, which has remained undiscovered until so recently, even though it is one of the three most robust species of the genus and largest sundew in the New World. Distribution and habitat:— Drosera magnifica is a microendemic species, so far only known to occur on the summit of the Pico do Padre Ângelo, in the municipality of Conselheiro Pena, eastern Minas Gerais state, Brazil (Figs. 1, 3A). The new species occurs on sandstone outcrops among herbaceous and shrubby vegetation in a vegetation type intermediate between campos rupestres (“rocky fields”) and campos de altitude (“highland fields”), in a narrowly defined habitat at elevations around 1500–1530 m (Fig. 3). Plants grew mostly in soil composed of a very loose layer of organic matter mixed with sand over sandstone, or more rarely in cracks of bare sandstone. On the Pico do Padre Ângelo, D. magnifica was observed to occur mostly at a single site on the south slope of the summit, with thousands of plants concentrated in an area of about 50 × 50 m (Fig. 3 B). This slope is approximately at a 45 -degree angle and receives significant moisture in the form of condensation from uplift winds. Two smaller subpopulations were seen on gentle slopes on the north side of the summit, distant ca. 200 m and 300 m from the main population, and bearing around 10 and 100 individuals, respectively. Typical members of the altitude vegetation growing together with D. magnifica are: the subshrub Baccharis platypoda Candolle (1836: 409) (Asteraceae), the bromeliad Vriesea sanctaparecidae Leme (2013: 45) (Bromeliaceae), as well as other species belonging to Asteraceae, Bromeliaceae, Melastomataceae, Orchidaceae, Rubiaceae, mosses and lichens (Fig. 3). Although a few pockets of Sphagnum Linnaeus (1753 b: 1106) moss were observed in the area, D. magnifica was not found growing with it, but only next to it. Because of their proximity and similar elevation, the Pico da Aliança (ca. 1440 m, 10 km to the southwest) and Pico do Pinh"o (ca. 1430 m, 5 km to the north) were also explored, but these were found to be comparatively drier and no D. magnifica populations were located. The only other peak in the vicinity likely to harbor D. magnifica is the Pico do Sossego (ca. 1550 m, 7 km to the north), which is still unexplored botanically. Phenology: —The available data indicates that the flowering period of D. magnifica is comprised between late dry season and early wet season (from October to December), with only a single inflorescence produced per mature rosette. No plants were seen in flower in May or July, when only dry old scapes were observed. Conservation Status: —Critically Endangered: CR B 1 ab(iii) + B 2 ab(iii). Drosera magnifica is a microendemic species, currently known to occur on a single mountain summit where it is locally abundant, but restricted to a fragile and isolated habitat. Habitat degradation was observed along most of the summit trail, caused by coffee and eucalypt plantations (Fig. 3 A), cattle ranching, and invasive species of grasses, such as “capim gordura” [Melinis minutiflora Palisot de Beauvois (1812: 54)], Brachiaria (Trinius 1826: 39) Grisebach (1853: 469) (Poaceae), and the fern Pteridium arachnoideum (Kaulfuss 1824: 190) Maxon (1924: 89) (Dennstaedtiaceae). Because of its highly restricted occurrence as well as the observed and projected decline of habitat quality, D. magnifica is here listed as Critically Endangered (CR) according to the criteria of IUCN (2012). The Pico do Padre Ângelo and surrounding mountains (including the Serra do Pinh"o and Pico da Aliança) should be a priority aim for conservation, as they contain some of the very last remaining areas of eastern Minas Gerais that are not completely degraded, and which harbor a unique and still very poorly-known biodiversity. The surrounding lowlands have been heavily deforested over the past century and only small patches of rainforest remain between cattle ranches and family farms. The species-rich and fragile campos rupestres found on these highlands harbor narrowly endemic taxa, such as the recently described bromeliads Alcantarea nana Leme (2014: 72), A. occulta Leme (2013: 10) and Vriesea sanctaparecidae (Leme & Kollmann 2013, Leme et al. 2014), as well as the orchid Cattleya alvarenguensis (Campacci 2014: 382) Berg (2014: 84), among several other still undescribed species (pers. obs.). Ecological notes: —All observed specimens of D. magnifica show a well-developed stem (Fig. 2 A), usually prostrate, but often erect and supported by surrounding shrubby vegetation, reaching 30–40 cm above the soil surface (Fig. 3 C–F). Stems were frequently observed to branch once (rarely more), and new growing tips were frequently seen sprouting from the stem bases (Fig. 3 F). In some cases, young plantlets were also observed emerging from roots. Not a single seedling was found during either of our visits, which is surprising considering the numerous flowers and the large quantity of seed produced by D. magnifica. Large numbers of insects (mostly from Hymenoptera: Terebrantia, as well as small Coleoptera, Diptera, and Lepidoptera) were observed stuck on the leaves of D. magnifica in November and May, but not as many in July. Nutrition obtained from the abundant prey may be an important factor in sustaining the surprising robustness of this new species as well as the fast growth rate (see below), since it grows in very scarce and structured soil over sandstone. Acephalous dipteran larvae were observed on many specimens of D. magnifica, hidden among the young leaves, as were also their pupae on the abaxial leaf surfaces. Similar dipteran larvae have previously also been observed by F.R. to live on the leaves of the related D. spiralis (pictured as living on “ D. graminifolia ” in McPherson 2010). Additional specimens examined Drosera magnifica (paratypes)— BRAZIL. Minas Gerais: Conselheiro Pena, Pico do Padre Ângelo, 1530 m, 0 8 July 2014, Gonella et al. 675 (SPF, M). Drosera graminifolia — BRAZIL. Minas Gerais: Crescit in summis montibus dictis Serra-da-Caraça; alt. circiter 6000 ped., February, Saint-Hilaire B 1-448 (P, holotype); Serra do Caraça, December 1830, Sellow 1300 (B, holotype of D. graminifolia var. major Eichl. in Mart. & Eichl.). Drosera spiralis — BRAZIL. Minas Gerais: Crescit in montibus dictis Serra de Curumatahy, ad rivulum Corgo Novo, in parte provinciae Minas Geraes dicta Distrito dos Diamantes, Saint-Hilaire B 1-2021 bis (P; holotype); Tejuco (Serro Frio) [currently Diamantina], May, Martius 1287 (M; original material of D. brasiliensis); inter Tejuco et Bandeirinhas, May, Martius s.n. (M). Drosera graminifolia — BRAZIL. Minas Gerais: Crescit in summis montibus dictis Serra-da-Caraça; alt. circiter 6000 ped., February, Saint-Hilaire B 1-448 (P, holotype); Serra do Caraça, December 1830, Sellow 1300 (B, holotype of D. graminifolia var. major Eichl. in Mart. & Eichl.). Drosera spiralis — BRAZIL. Minas Gerais: Crescit in montibus dictis Serra de Curumatahy, ad rivulum Corgo Novo, in parte provinciae Minas Geraes dicta Distrito dos Diamantes, Saint-Hilaire B 1-2021 bis (P; holotype); Tejuco (Serro Frio) [currently Diamantina], May, Martius 1287 (M; original material of D. brasiliensis); inter Tejuco et Bandeirinhas, May, Martius s.n. (M).Published as part of Paulo Minatel Gonella, Fernando Rivadavia & Andreas Fleischmann, 2015, Drosera magnifica (Droseraceae): the largest New World sundew, discovered on Facebook, pp. 257-267 in Phytotaxa 220 (3) on pages 258-264, DOI: 10.11646/phytotaxa.220.3.4, http://zenodo.org/record/27022
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