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- New taxa to the flora of Madeira archipelago islands (Portugal)Publication . Jardim, Roberto; Sequeira, Miguel Menezes de73 new references for 72 taxa of vascular plant are here reported for the Madeira archipelago. 55 not previously recorded for Desertas Islands, 12 to Porto Santo Island and 6 for Madeira Island. Of the 72 taxa, 28 are xenophytes, and 10 are new taxa to the flora of the archipelago (of these 9 are xenophytes). Their native status, taxonomy and distribution are briefly discussed. Keywords: Madeira archipelago; vascular plants; new records; xenophytes.
- Rediscovering of Chara braunii (Characeae, Charophyta) in Madeira (Macaronesian region, Portugal)Publication . Medina, Leopoldo; Nascimento, Pedro; Sequeira, Miguel Menezes deChara braunii C.C. Gmelin (Characeae, Charophyta) was found in Madeira Island (Portugal) in a water channel in an agricultural area. This constitutes the first record of that species since 1944 in the Macaronesian region (Azores, Madeira and Canary archipelagos).
- RAS gene polymorphisms, classical risk factors and the advent of coronary artery disease in the Portuguese populationPublication . Freitas, Ana I.; Mendonça, Isabel; Brión, Maria; Sequeira, Miguel M.; Reis, Roberto P.; Carracedo, Angel; Brehm, AntónioBackground: Several polymorphisms within the renin-angiotensin system cluster of genes have been associated with the advent of coronary artery disease (CAD) or related pathologies. We investigated the distribution of 5 of these polymorphisms in order to find any association with CAD development and distinguish if any of the biochemical and behavioural factors interact with genetic polymorphisms in the advent of the disease. Methods: ACE I/D (rs4340), ACE A11860G (rs4343), AT1R A1166C (rs5186), AGT T174M (rs4762) and AGT M235T (rs699) gene polymorphisms were PCR-RFLP analysed in 298 CAD patients and 510 controls from Portugal. Several biochemical and behavioural markers were obtained. Results: ACE I/D DD and ACE11860 GG genotypes are risk factors for CAD in this population. The simultaneous presence of ACE I/D I and ACE11860 A alleles corresponds to a significant trend towards a decrease in CAD incidence. We found several synergistic effects between the studied polymorphisms and classical risk factors such as hypertension, obesity, diabetes and dyslipidaemia: the presence of the DD genotype of ACE I/D (and also ACE11860 GG) increases the odds of developing CAD when associated to each one of these classical risk factors, particularly when considering the male and early onset CAD subgroup analysis; AGT235 TT also increases the CAD risk in the presence of hypertension and dyslipidaemia, and AT1R1166 interacts positively with hypertension, smoking and obesity. Conclusion: ACE polymorphisms were shown to play a major role in individual susceptibility to develop CAD. There is also a clear interaction between RAS predisposing genes and some biochemical/environmental risk factors in CAD onset, demonstrating a significant enhancement of classical markers particularly by ACE I/D and ACE11860.
- Two new alien fern taxa for Madeira Island (Portugal)Publication . Ferreira, João Pedro; Cabral, Laura; Brazão, André; Nascimento, Pedro; Sequeira, Miguel Menezes deThe Madeira archipelago vascular flora includes 74 pteridophyte taxa. Of these, eight are exclusive endemics, eight are Macaronesian endemics, being the vast majority, 44, native and 14 referred as introduced taxa. The total number of alien vascular plant taxa is 401 (i.e. 33% of the total flora). The recent detection of several fully naturalized alien fern taxa is a process parallel to that observed in other groups of vascular plants. The occurrence of Pteris nipponica W.C. Shieh (syn. Pteris cretica L. var. albolineata Hooker) and Goniophlebium subauriculatum (Blume) C. Presl as new naturalized plants is recorded for the first time for the island of Madeira.
- Multiplexed-shotgun-genotyping data resolve phylogeny within a very recently derived insular lineagePublication . Mort, Mark E.; Crawford, Daniel J.; Kelly, John K.; Santos-Guerra, Arnoldo; Sequeira, Miguel Menezes de; Moura, Mónica; Caujapé-Castells, JuliPremise of the study: Endemic plants on oceanic islands have long served as model systems for studying patterns and processes of evolution. However, phylogenetic studies of island plants frequently illustrate a decoupling of molecular divergence and ecological/morphological diversity, resulting in phylogenies lacking the resolution required to interpret patterns of evolution in a phylogenetic context. The current study uses the primarily Macaronesian fl owering plant genus Tolpis to illustrate the utility of multiplexed shotgun genotyping (MSG) for resolving relationships at relatively deep (among archipelagos) and very shallow (within archipelagos) nodes in this small, yet diverse insular plant lineage that had not been resolved with other molecular markers. • Methods: Genomic libraries for 27 accessions of Macaronesian Tolpis were generated for genotyping individuals using MSG, a form of reduced-representation sequencing, similar to restriction-site-associated DNA markers (RADseq). The resulting data fi les were processed using the program pyRAD, which clusters MSG loci within and between samples. Phylogenetic analyses of the aligned data matrix were conducted using RAxML. • Key results: Analysis of MSG data recovered a highly resolved phylogeny with generally strong support, including the fi rst robust inference of relationships within the highly diverse Canary Island clade of Tolpis . • Conclusions: The current study illustrates the utility of MSG data for resolving relationships in lineages that have undergone recent, rapid diversifi cation resulting in extensive ecological and morphological diversity. We suggest that a similar approach may prove generally useful for other rapid plant radiations where resolving phylogeny has been diffi cult.
- Richard Thomas Lowe, an unknown Botanical IllustratorPublication . Mesquita, Sandra; Castel-Branco, Cristina; Sequeira, Miguel Menezes deIllustration is undoubtedly part of botanical history. In the early 19th century, as botanical Latin yielded more accurate descriptions, the need for illustration in scientific publications decreased. Nevertheless, advances in printing processes boosted the production of illus trated botanical periodicals at accessible costs. Therefore, coloured depictions of plants never ceased to be part of botany at all levels. Richard Thomas Lowe (1802-1874) studied the flora of Madeira from 1826, when he first visited the island, to his death. He is well known as the author of Madeira’s first comprehensive Flora, but his work as a botanical illustrator is poorly known. We analysed the graphic production related to his first major paper, published in 1831, along with written documents, which, altogether, support a more complete understanding of Rev. Lowe’s botanical work in Madeira and his relevant activity as an illustrator. We believe that joint analysis of illustrations and correspondence show that Lowe himself made the drawings after which the plate of the orchid Goodyera macrophylla in this paper was prepared, whose authorship was, up to now, unknown.
- Karyological analysis of the five native Macaronesian Festuca (Gramineae) grasses supports a distinct diploid origin of two schizoendemic groupsPublication . Sequeira, Miguel Menezes de; Díaz-Pérez, Antonio; Santos-Guerra, Arnoldo; Viruel, Juan; Catalán, PilarMenezes de Sequeira, M., Díaz-Pérez, A., Santos-Guerra, A., Viruel, J. & Catalán, P. 2009. Karyological analysis of the five na tive Macaronesian Festuca (Gramineae) grasses supports a dis tinct diploid origin of two schizoendemic groups. Anales Jard. Bot. Madrid 66(1): 55-63. A karyological analysis has been conducted of all five native Macaronesian Festuca grasses belonging to fine-leaved F. subg. Festuca sect. Aulaxyper and broad-leaved F. subg. Drymanthele sect. Phaeochloa Loliinae lineages. Chromosomal analyses were made in 30 plants corresponding to 17 populations of the fine leaved F. agustinii, F. jubata, F. francoi and F. petraea and 2 pop ulations of the broad-leaved F. donax. All counts except one tetraploid count were diploids, showing 2n = 14 chromosomes. Diploidy was confirmed for the robust F. donax, nested within a clade of relict ancestral fescues as reported in recent phyloge netic studies, and was also found in the more slender F. agus tinii, F. jubata, F. francoi and F. petraea, which are basal to a re cently evolved clade of polyploid red fescues. Karyotypes of the two groups are however distinct, with broad-leaved F. donax showing larger and more regular chromosomes and all four fine-leaved taxa showing smaller and more irregular submeta centric chromosomes. Our karyological data indicate that these two groups of diploid fescues correspond to distinct schizoen demics which apparently originated at different times after in dependent continental colonizations of Macaronesia
- Sonchus parathalassius J.G. Costa ex R. Jardim & M. Seq., a new species from Porto Santo Island (Madeira Archipelago)Publication . Jardim, Roberto José Abreu; Sequeira, Miguel Pinto da Silva Menezes de
- Jatrophane and lathyrane diterpenoids from Euphorbia hyberna LPublication . Ferreira, Ana Margarida V. D.; Carvalho, Luı́s H. M.; Carvalho, Maria João M.; Sequeira, Miguel M.; Silva, Artur M. S.A new diterpene tetraester, from the jatrophane family, and two new diterpene triesters, with a lathyrane skeleton, have been isolated from the chloroform extract of the roots of Euphorbia hyberna L. The structures of these compounds have been established by spectroscopic methods, including 2D NMR experiments.
- Holcus azoricus M. Seq. & Castrov. (Poaceae), a new species from the Azores IslandsPublication . Sequeira, Miguel Menezes de; Castroviejo, SantiagoA new species of Holcus L. (Poaceae), endemic to the Azores archipelago (Portugal), is described. The vegetative and reproductive structures were studied. The diagnostic characters were compared with those of closely related species. New chromosome counts in Holcus azoricus M. Seq. & Castrov. (2n = 35) and H. rigidus Hochst. (2n = 28) are included. A possible hybrid origin is hypothesized; the potential parents are H. lanatus L. and H. rigidus.