SEM and Light Microscope Observations on Fruit and Seeds in Scrophulariaceae from Southwest Spain and their Systematic Significance

Many studies of the morphology and anatomy of fruits and seedsof Scrophulariaceae from Southwest Spain have been made. Thesystematic utility of characteristics of these plant structuresis discussed in order to determine relationships among the differentgenera included in this widely distributed family. The mostuseful fruit features for this study were the indumentum, capsuledehiscence and structure of the endocarp, seed-coat ornamentation,and inner structure of the seeds. In addition, phenetic analysisof 58 characters revealed that several groups of genera in Scrophulariaceaeare closely related on the basis of their fruit and seed features.The phenetic relationships of genera or groups of genera arediscussed. Keys to genera considered in this work, using exclusivelyfruit or seed characters, are provided. Lastly, the usual dispersalsystems observed in this family are discussed. Copyright 2000Annals of Botany Company Fruit, seed, morphology, anatomy, Scrophulariaceae, phenogram, SEM, pericarp, dehiscence, indumentum, seed-coat     

Phylogenetic significance of morphological characters in the tropical Hypotrachyna clade of parmelioid lichens (Parmeliaceae, Ascomycota)

Lichen-forming ascomycetes exhibit often complex morphologies of the vegetative thallus that are usually not found in non-lichenized fungi. This includes the thallus organization and appendical structures associated with the main thallus, such as cilia and rhizines. Such morphological characters are widely employed in the taxonomy of parmelioid lichens, especially at generic level. Within parmelioid lichens, several monophyletic groups can be distinguished, the Hypotrachyna clade being one of them, which includes mostly tropical taxa. In this first molecular study focused specifically on the Hypotrachyna clade, we used maximum parsimony and Bayesian analyses of a combined data set of nuclear ITS and mitochondrial SSU rDNA sequences to (1) test the monophyly of genera presently accepted within the clade and (2) evaluate the phylogenetic value of the morphological characters used to circumscribe genera in parmelioid lichens. Out of the 89 mtSSU and 88 nuITS sequences included in the present study, 121 sequences were newly obtained. Our results show that the taxa within the clade fall into two major groups and that the genus Hypotrachyna is polyphyletic. Everniastrum and Parmelinopsis are nested within Hypotrachyna sensu stricto, the latter being also polyphyletic. Bulbothrix is paraphyletic with Parmelinella nested within and is basal to the second major Hypotrachyna clade. Monophylies of Bulbothrix and Hypotrachyna are significantly rejected. The phylogenetic analysis demonstrates that morphological characters currently used to circumscribe genera in parmelioid lichens, such as cortical anatomy, lobe configuration, cilia, and rhizines have been overestimated and have only minor value in identifying monophyletic groups.     

Relationships among "ancient araliads" and their significance for the systematics of Apiales

The relationship between the angiosperm families Apiaceae and Araliaceae (order Apiales) has been difficult to resolve, due in large part to problems associated with taxa characterized by a mixture of features typical of both families. Among such confounding groups are the araliads Delarbrea, Pseudosciadium, Myodocarpus, Mackinlaya, and Apiopetalum and many members of Apiaceae subfamily Hydrocotyloideae. Traditional systems have often envisioned these taxa as phyletic intermediates or bridges between the two families. To reevaluate the phylogenetic position of the "intermediate" araliad genera, molecular data were collected from nuclear (rDNA ITS) and plastid (matK) sequences from a complete or near-complete sampling of species in each genus. When analyzed with samples representing the other major clades now recognized within Apiales, results confirm and expand the findings of previously published studies. The five araliad "intermediates" are placed within two well-supported clades clearly segregated from the "core" groups of both Apiaceae and Araliaceae. These segregate clades closely parallel traditional definitions of the araliad tribes Myodocarpeae (Delarbrea, Pseudosciadium, and Myodocarpus) and Mackinlayeae (Mackinlaya and Apiopetalum), and relationships among the species within these clades are largely supported by morphological and anatomical data. Based on these results, Myodocarpeae and Mackinlayeae may best be treated as distinct families. This approach would render four monophyletic groups within Apiales, to which a fifth, Pittosporaceae, cannot at present be excluded. Sampling of taxa from Hydrocotyloideae remains preliminary, but results confirm previous studies indicating the polyphyly of this subfamily: hydrocotyloid taxa may be found in no fewer than three major clades in Apiales.     

Multiple origin of the tropical forest tree family Icacinaceae

Analyses of DNA sequences from four genes (ndhF, rbcL, atpB, and 18S rDNA) and morphological data show that the members of the tropical forest tree family Icacinaceae do not have a common origin. All of the genera earlier placed in Icacinaceae are euasterids but placed in the following three different orders: Garryales, Aquifoliales, and Apiales. Icacina and related genera are members of Garryales and, pending more data, are still best treated as Icacinaceae (sensu stricto). The genera related to Aquifoliales are placed in Cardiopteridaceae and a new family, Stemonuraceae. The genus Pennantia is a member of Apiales and the family Pennantiaceae is recognized. Morphological characters delimiting these groups are discussed. Twenty-six new ndhF sequences were obtained for the study (25 from former Icacinaceae and 1 from Cardiopteris).     

Phenetic and cladistic relationships among tenebrionid beetles (Coleoptera)

Abstract. The higher classification of Tenebrionidae is analysed using numerical phenetic, numerical cladistic and traditional Hennigian methods. In all, eighty characters are examined for about 335 taxa; definitive analyses are made on combinations of eighteen to seventy characters for thirty-three OTUs. At lower levels of relationship (genera and closely related tribes) phenetic and cladistic classifications are shown to be congruent, but at higher levels (tribes and subfamilies) there is marked discordance with phenetic results being more stable. A consensus classification is more similar to the Hennigian cladogram than is any single computer generated cladogram. Two main tribal groups – the Lagrioid and Tenebrionoid groups – are suggested which differ in defensive glands, female anatomy, wing and mouthpart morphology, larval characters and other features. The Tenebrionoid group consists of three main subdivisions – the tenebrionine, coelometopine and diaperine lineages. Changes in classificatory position are recommended for eighty-seven genera and tribes (listed in Appendix E) and implied for numerous others.     

A phylogenetic analysis of 100+ genera and 50+ families of euasterids based on morphological and molecular data with notes on possible higher level morphological synapomorphies

 A data matrix of 143 morphological and chemical characters for 142 genera of euasterids according to the APG system was compiled and complemented with rbcL and ndhF sequences for most of the genera. The data were subjected to parsimony analysis and support was assessed by bootstrapping. Strict consensus trees from analyses of morphology alone and morphology + rbcL + ndhF are presented. The morphological data recover several groups supported by molecular data but at the level of orders and above relationships are only superficially in agreement with molecular studies. The analyses provide support for monophyly of Gentianales, Aquifoliales, Apiales, Asterales, and Dipsacales. All data indicate that Adoxaceae are closely related to Dipsacales and hence they should be included in that order. The trees were used to assess some possible morphological synapomorphies for euasterids I and II and for the orders of the APG system. Euasterids I are generally characterised by opposite leaves, entire leaf margins, hypogynous flowers, “early sympetaly” with a ring-shaped corolla primordium, fusion of stamen filaments with the corolla tube, and capsular fruits. Euasterids II often have alternate leaves, serrate-dentate leaf margins, epigynous flowers, “late sympetaly” with distinct petal primordia, free stamen filaments, and indehiscent fruits. It is unclear which of these characters represent synapomorphies and symplesiomorphies for the two groups, respectively, and there are numerous expections to be interpreted as reversals and parallelisms. Received August 28, 2000 Accepted August 7, 2001     

Phylogenetic classification of the Drosophilidae Rondani (Diptera): the role of morphology in the postgenomic era

Molecular sequences now overwhelm morphology in phylogenetic inference. Nonetheless, most molecular studies are conducted on a limited number of taxa, as DNA rarely can be analysed from old museum types or fossils. During the last 20 years, more than 150 molecular studies have challenged the current phylogenetic classification of the family Drosophilidae Rondani based on morphological characters. Most studies concerned a single genus, Drosophila Fallén, and included only few representative species from 17 out of the 78 genera of the family. Therefore, these molecular studies were unable to provide an alternative classification scheme. A supermatrix analysis of seven nuclear and one mitochondrial genes (8248 bp) for 33 genera was conducted using outgroups from one calyptrate and four ephydroid families. The Bayesian phylogeny was consistent with previous molecular studies including whole genome sequences and divided the Drosophilidae into four monophyletic clades. Morphological characters, mostly male genitalia, then were compared thoroughly between the four clades and homologous character states were identified. These states were then checked for 70 genera and a revised phylogenetic, family‐group classification for the Drosophilidae is proposed. Two genera –Cladochaeta Coquillett and Diathoneura Duda – of the tribe Cladochaetini Grimaldi are transferred to the family Ephydridae. The Drosophilidae is divided into two subfamilies: Steganinae Hendel (30 genera) and Drosophilinae Rondani (43 genera). A further two genera, Apacrochaeta Duda and Sphyrnoceps de Meijere, are incertae sedis, and Palmophila Grimaldi, is synonymized with Drosophila syn.n. The Drosophilinae is subdivided into two tribes: the re‐elevated Colocasiomyini Okada (nine genera) and Drosophilini Okada. The paraphyly of the genus Drosophila was not resolved to avoid affecting the binomina of important laboratory model species; however, its subgeneric classification was revised in light of molecular and morphological data. Three subgenera, namely Chusqueophila Brncic, Phloridosa Sturtevant and Psilodorha Okada, were synonymized with the subgenus Drosophila (Drosophila) Fallén syns.n. Among the 45 species groups and 5 species complexes of Drosophila (Drosophila), 22 groups and 1 complex were transferred to the subgenus Drosophila (Siphlodora) Patterson & Mainland and 6 groups, 2 species subgroups and 3 complexes are considered incertae sedis within the genus Drosophila. Different morphological characters provide different signals at different phylogenetic scales: thoracic characters (wing venation and presternal shape) discriminate families; grasping and erection‐related characters discriminate subfamilies to tribes; whereas phallic paraphyses, i.e. auxiliary intromittent organs, discriminate genera and Drosophila subgenera. The study shows the necessity of analysing morphological characters within a molecular phylogenetic framework to translate molecular phylogenies into taxonomically‐comprehensive classifications.     

Morphology and biogeography of Apiaceae subfamily Saniculoideae as inferred by phylogenetic analysis of molecular data

The phylogenetic placements of several African endemic genera at the base of Apiaceae subfamilies Saniculoideae and Apioideae have revolutionized ideas of relationships that affect hypotheses of character evolution and biogeography. Using an explicit phylogeny of subfamily Saniculoideae, we reconstructed the evolutionary history of phenotypic characters traditionally important in classification, identified those characters most useful in supporting relationships, and inferred historical biogeography. The 23 characters examined include those of life history, vegetative morphology, inflorescences, and fruit morphology and anatomy. These characters were optimized over trees derived from maximum parsimony analysis of chloroplast DNA trnQ-trnK sequences from 94 accessions of Apiaceae. The results revealed that many of these characters have undergone considerable modification and that traditional assumptions regarding character-state polarity are often incorrect. Infrasubfamilial relationships inferred by molecular data are supported by one to five morphological characters. However, none of these morphological characters support the monophyly of subfamilies Saniculoideae or Apioideae, the clade of Petagnaea, Eryngium and Sanicula, or the sister-group relationship between Eryngium and Sanicula . Southern African origins of Saniculoideae and of its tribes Steganotaenieae and Saniculeae are supported based on dispersal-vicariance analysis.     

Evolution in Apiales: nuclear and chloroplast markers together in (almost) perfect harmony

Relationships within the angiosperm order Apiales have long been difficult to interpret. Traditionally, the order comprised two families, Apiaceae and Araliaceae. Recent studies, however, suggest three additional lineages should also be recognized in the order (Pittosporaceae plus two tribes segregated from Araliaceae, Mackinlayeae and Myodocarpeae), and that one taxon (Apiaceae subfamily Hydrocotyloideae) is polyphyletic. Nuclear data also support the placement of five enigmatic genera ( Aralidium , Griselinia , Melanophylla , Pennantia and Torricellia ) within an expanded Apiales. To date, detailed molecular studies of Apiales have relied largely on data derived from plastid sequences, especially mat K and rbc L. To test and complement the results of these studies, the 26S (large subunit) of nuclear ribosomal DNA was sequenced and analysed phylogenetically. Results from this study confirm that Apiales comprise five major lineages: core Apiaceae, core Araliaceae, Pittosporaceae, the Mackinlaya group and the Myodocarpus group. Moreover, using an expanded sampling of members of subfamily Hydrocotyloideae, the nature and extent of the polyphyly is confirmed, with members of this taxon found among four distinct clades within Apiales. © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 144 , 123–147.     

Phylogeny of the genus Peperomia (Piperaceae) inferred from the trnK/matK region (cpDNA)

The genus Peperomia is one of the largest genera of basal angiosperms, comprising about 1500-1700 pantropically distributed species. The currently accepted infrageneric classification divides Peperomia into nine subgenera and seven sections. This classification is based on some 200 species, primarily using fruit morphology. The monophyly of these infrageneric taxa has never been tested and molecular phylogenetic studies of a representative sampling within Peperomia do not exist. This paper provides the first molecular phylogeny for the genus Peperomia. Monophyletic clades within Peperomia are identified and previously used morphological characters are critically reviewed. We show that the importance of some morphological characters has been overestimated and that some of these characters presumably have evolved several times independently. Only one previously described subgenus has been confirmed to be monophyletic.     

Classification of trypanosomatids from fruits and seeds using morphological, biochemical and molecular markers revealed several genera among fruit isolates

Trypanosomatids are widespread in several plant families and although most isolates have been classified as Phytomonas, other trypanosomatid genera can also infect plants. In order to assess the natural occurrence of non-Phytomonas trypanosomatids in plants we characterized 21 new trypanosomatid cultures, 18 from fruits and three from seeds of 17 plant species. The trypanosomatids from fruit and seeds were compared in terms of morphological, growth, biochemical and molecular features. The high diversity among the isolates permitted the classification of the new flagellates into the genera Crithidia and Leptomonas as well as Phytomonas. The data showed that natural fruit infection with non-Phytomonas trypanosomatids is more common than usually thought, being detected in 43% of the fruit isolates.     

Correlations among fruit traits and evolution of different fruits within Melastomataceae

The anatomy and morphology of nearly mature fruits in 85 mainly palaeotropical species of Melastomataceae were examined using microtome- and hand-sectioning, and differential staining. Much structural heterogeneity was observed in both capsules and berries. Mul-tivariate analyses of 31 of the 52 characters recorded for each species, revealed that indehiscence is associated with fusion of ovary and hypanthium tissues, placenta persistence, lack of a persistent endocarp, and a dearth of srlereids in these tissues, while dehiscenre is correlated with the opposite states and a persistent exocarp. Other fruit characters such as lignification or fleshiness of tissues do not show a consistent association with dehiscence. Break down of broad fruit types, such as 'berry' and 'capsule', into their individual morphological and anatomical traits shows how unusual fruit types, such as woody berries, fleshy capsules, and capsules containing fleshy placentas (display fruits), which are common in palaeotropical Melastomeae and Dissochaeteae, contribute to a loosening of expected correlations. Thus, discriminant analysis clearly differentiated display fruits from the other fruit types because of their combination of fleshy placentas with a persistent endocarp and absence of ovary/hypanthium fusion. The evolution of fruit types within Melastomataceae, and especially Dissochaeteae, and their reliability as phylogenetic indicators is discussed in the light of molecular phylogenies for these groups that show that berries and capsules evolved several times independently, explaining the observed heterogeneity of outwardly similar fruits. Fruit diversity within Melastoma , a monophyletic genus of 22 species, provides an example of the plasticity afforded by the particular construction of Melastomataceae fruits, which has contributed to ecological diversification in melastome seed dispersal.     

Comparative leaf anatomy of New Zealand and Tasmanian Inuleae (Compositae)

Leaf anatomy is compared for 47 taxa of the tribe Inuleae (Compositae) from New Zealand and Tasmania. The taxa are tabulated according to their lamina structure. Noteworthy anatomical features are lamina type and grade of differentiation, stomatal position, epidermis and cuticle thickness, shape of palisade cells, number of bundle-sheath layers; presence or absence of sclerenchyma caps, water storage cells, secretory canals, abaxial collenchyma and protruding midrib. It is shown that leaf anatomy data provide characters which are taxonomically useful in classification of Inuleae.     

Clarification of the relationship beteen Apiaceae and Araliaceae based on matK and rbcL sequence data

Apiaceae and Araliaceae (Apiales) represent a particularly troublesome example of the difficulty in understanding evolutionary relationships between tropical-temperate family pairs. Previous studies based on rbcL sequence data provided insights at higher levels, but were unable to resolve fully the family-pair relationship. In this study, sequence data from a more rapidly evolving gene, matK, was employed to provide greater resolution. In Apiales, matK sequences evolve an average of about two times faster than rbcL sequences. Results of phylogenetic analysis of matK sequences were first compared to those obtained previously from rbcL data; the two data sets were then combined and analyzed together. Molecular analyses confirm the polyphyly of apiaceous subfamily Hydrocotyloideae and suggest that some members of this subfamily are more closely related to Araliaceae than to other Apiaceae. The remainder of Apiaceae forms a monophyletic group with well-defined subclades corresponding to subfamilies Apioideae and Saniculoideae. Both the matK and the combined rbcL-matK analyses suggest that most Araliaceae form a monophyletic group, including all araliads sampled except Delarbrea and Mackinlaya. The unusual combination of morphological characters found in these two genera and the distribution of matK and rbcL indels suggest that these taxa may be the remnants of an ancient group of pro-araliads that gave rise to both Apiaceae and Araliaceae. Molecular data indicate that the evolutionary history of the two families is more complex than simple derivation of Apiaceae from within Araliaceae. Rather, the present study suggests that there are two well-defined "families," both of which may have been derived from a lineage (or lineages) or pro-araliads that may still have extant taxa.