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The Malesian genus Eugeissona, with six species, is sister to all other Calamoideae, which are in turn sister to all other Arecaceae. The structure of its gynoecium and fruit is thus potentially of great interest in understanding gynoecium evolution in calamoid palms and in Arecaceae as a whole. The wall of the incompletely trilocular gynoecium of Eugeissona is thick and differentiated into several topographic zones, with a well‐developed vascular system even before pollination. During gynoecium and fruit development, the outer and inner epidermises are little specialized and form the exocarp and endocarp (obliterated in the mature fruit), respectively. In contrast, the mesophyll of the carpels differentiates strongly and is markedly specialized: four massive topographic zones are easily distinguished within the mesocarp. The peripheral zone of the mesocarp forms the body of the scales (a synapomorphy for Calamoideae). The second and the fourth zones are multilayered and parenchymatous with a massive derived vascular system in the former. The third zone of the mesocarp comprises a stout sclerenchymatous pyrene, made of fibre‐like sclereids, the innermost bundles of the derived vascular system and dorsal, ventral and lateral vascular bundles. The fruits of all other Calamoideae lack the sclerenchymatous pyrene and thus differ dramatically from Eugeissona fruits. The similarity of the processes of histogenesis during gynoecium and fruit development in Eugeissona with those in Nypa and borassoid palms, suggests these features could be plesiomorphic for the family. © 2012 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, 168 , 377–394.  相似文献   
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Quedius antipodum Sharp is an endemic species from New Zealand. Here we describe its larva, the first of the species‐rich group of the south temperate ‘Quedius’ spp. This finding throws light on the controversy between the conventional systematics of Quedius Stephens and newer phylogenetic analyses, both of which are based on non‐larval characters only. We compare the larva of Q. antipodum with those of the north temperate Quedius (Quediina), where it was traditionally placed, and with the known larvae of Amblyopinina, a group where Q. antipodum was placed by recent phylogenetic studies. Sister‐group relationships of Q. antipodum within the tribe Staphylinini are explored based on larvae by means of parsimony analysis: 77 morphological characters scored for 20 species from 17 genera. Consistent with the adult morphology and DNA sequences, larvae‐based cladistic analysis confirms that Q. antipodum should not be placed in the north temperate genus Quedius. However, larval analysis alone remains dubious with respect to finding the exact sister relationships of that species.  相似文献   
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This study aimed to identify the sister group of the poorly known and morphologically isolated Burmese species Quedius lineipennis within the tribe Staphylinini (Staphylinidae: Staphylininae) using morphological characters. Phylogenetic analysis of a broad taxon sample demonstrated that this Asian species is not a member of the genus Quedius but forms the sister taxon to the Neotropical genus Quediomacrus. Both taxa were shown to be members of a hitherto unrecognized lineage with a highly disjunct distribution. The lineage is hypothesized to be Asian in origin, with dispersals to the Americas during the early Eocene climatic maximum via Beringia and to Australia via land connections in the late Miocene. The current distribution of the lineage is considered to be relictual. New phylogenetic hypotheses within ‘Quediina’ and Staphylinini as a whole are proposed and the general tree topology of Staphylinini recovered by recent morphological studies is refined. Phylogenetic relationships within the Quedius complex remain unclear. Alesiella Brunke and Solodovnikov gen.n. , is erected for Quedius lineipennis and the Quedius subgenus Quedionuchus is reinstated to genus level with new combinations as follows: Quedionuchus atl (Smetana, 1975), comb.n. ; Quedionuchus calli (Smetana, 1976), comb.n. ; Quedionuchus cipactli (Smetana, 1976), comb.n. ; Quedionuchus coatl (Smetana, 1976), comb.n. ; Quedionuchus ehacatl (Smetana, 1976), comb.n. ; Quedionuchus ollin (Smetana, 1976), comb.n. ; Quedionuchus ozomatli (Smetana, 1975), comb.n. ; Quedionuchus reitterianus (Bernhauer, 1944), comb.n. ; Quedionuchus samuraicus (Bernhauer and Schubert, 1916), comb.n. ; Quedionuchus schultzei (Smetana, 1975), comb.n. ; Quedionuchus tecpatl (Smetana, 1976), comb.n. ; Quedionuchus xochitl (Smetana, 1976). Quedius lugubris Lokay, 1913 is transferred from the subgenus Quedionuchus to the subgenus Distichalius and placed in synonymy: Quedius punctatellus (Heer, 1839) = Quedius lugubris Lokay, 1913, syn.n . This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:9C7D3C90‐FCB9‐414F‐911B‐194A1A6602DE .  相似文献   
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The indehiscent fruitlets of the apparently basalmost extant angiosperm, Amborella trichopoda, have a pericarp that is differentiated into five zones, a thin one‐cell‐layered skin (exocarp), a thick fleshy zone of 25–35 cell layers (outer mesocarp), a thick, large‐celled sclerenchymatous zone (unlignified) of 6–18 cell layers (middle mesocarp), a single cell layer with thin‐walled (silicified?) cells (inner mesocarp), and a 2–4‐cell‐layered, small‐celled sclerenchymatous zone (unlignified) derived from the inner epidermis (endocarp). The border between inner and outer mesocarp is not even but the inner mesocarp forms a network of ridges and pits; the ridges support the vascular bundles, which are situated in the outer mesocarp. In accordance with previous observations by Bailey & Swamy, no ethereal oil cells were observed in the pericarp; however, lysigenous cavities as mentioned by these authors are also lacking; they seem to be an artefact caused by re‐expanding dried fruits. The seed coat is not sclerified. The fruitlets of Amborella differ from externally similar fruits or fruitlets in other basal angiosperms, such as Austrobaileyales or Laurales, in their histology. © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society, 2005, 148 , 265–274.  相似文献   
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The fossil genus of rove beetles Apticax gen.n . with two new species, A. volans sp.n . and A. solidus sp.n., is described from the Nova Olinda Member of the Crato Formation in north‐eastern Brazil (Aptian–Albian, dated as 125–99.6 Ma old). Both species belong to the clade Staphylininae + Paederinae in the staphylinine group of subfamilies and are the first fossil true Staphylinidae to be described from the entire Southern Hemisphere. Although they resemble Paederinae, the low number of satisfactorily preserved characters do not allow definite placement of either A. volans or A. solidus in any of the subfamilies of Staphylinidae.  相似文献   
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Metalloproteinases have a critical role in a broad spectrum of cellular processes ranging from the breakdown of extracellular matrix to the processing of signal transduction-related proteins. These hydrolytic functions underlie a variety of mechanisms related to developmental processes as well as disease states. Structural analysis of metalloproteinases from both invertebrate and vertebrate species indicates that these enzymes are highly conserved and arose early during metazoan evolution. In this regard, studies from various laboratories have reported that a number of classes of metalloproteinases are found in hydra, a member of Cnidaria, the second oldest of existing animal phyla. These studies demonstrate that the hydra genome contains at least three classes of metalloproteinases to include members of the 1) astacin class, 2) matrix met-alloproteinase class, and 3) neprilysin class. Functional studies indicate that these metalloproteinases play diverse and important roles in hydra morphogenesis and ce  相似文献   
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