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Synapomorphy
Kinds of Synapomorphy Selected AbstractsFrontal Fusion: Collapse of Another Anthropoid SynapomorphyTHE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 3 2008Alfred L. Rosenberger Abstract We test the hypothesis that the fused interfrontal suture of anthropoids is a uniquely distinguishing feature and a derived characteristic indicative of their monophyletic origin. Our survey of nonanthropoid primates and several archontan families indicates frontal fusion is widespread. It is most variable (fused, open or partially fused) inter- and intra-specifically among strepsirhines. The frontal bone is more commonly fused in living lemuroids and indrioids than among lorisoids. It appears to be fused regularly among Eocene adapids. Among nonanthropoid haplorhines, the interfrontal is fused in Tarsius, even in neonates and invariably in adults, probably also in all fossil tarsiiforms preserving the frontal bone, and in the late Eocene protoanthropoid Rooneyia. The plesiadapiform pattern remains uncertain, but fusion is ubiquitous among living tree shrews, colugos and bats. Distributional evidence implies that interfrontal fusion was present in the last common ancestor (LCA) of haplorhine primates and possibly in the LCA of euprimates as well. Anthropoids, therefore, cannot be defined cladistically by interfrontal fusion, not out of concern for homoplasy but because it is probably a primitive feature inherited from other taxa related to anthropoids. Fusion of the large anthropoid frontal bone, which was extended anteriorly to roof the orbits and expanded laterally in connection with a wide forebrain in the LCA of anthropoids and protoanthropoids, may have been preadaptive to the evolution of the postorbital septum. The zygomatico-frontal suture of the septum may provide an alternative mechanism for dissipating the calvarial strains of mastication formerly taken up by an open interfrontal suture. Anat Rec, 291:308,317, 2008. © 2008 Wiley-Liss, Inc. [source] A Light and Scanning Electron Microscopic Study of the Closing Apparatus in Tintinnid Ciliates (Ciliophora, Spirotricha, Tintinnina): A Forgotten SynapomorphyTHE JOURNAL OF EUKARYOTIC MICROBIOLOGY, Issue 4 2010SABINE AGATHA ABSTRACT. A membranous closing apparatus shuts the lorica opening in disturbed tintinnids of six genera belonging to four families. The homology of the apparatuses is investigated, using data from the literature and Mediterranean tintinnids studied in vivo and by scanning electron microscopy. Morphological and functional similarities indicate that the foldable closing apparatus is not only a synapomorphy of the genera Codonella (Codonellidae) and Dictyocysta (Dictyocystidae), as suggested 80 years ago, but also of Codonaria (Codonellidae) and Codonellopsis (Codonellopsidae). In Codonaria, Codonella, and Dictyocysta, the apparatuses merge posteriorly into membranous lorica sacs, which probably represent homologous structures. The diagnoses of these genera are improved according to the new findings. The close relationship of Codonella, Codonellopsis, and Dictyocysta is also inferred from small subunit rRNA phylogenies and the ultrastructure of the capsules. It contradicts the current lorica-based classification of the tintinnids. The assumption that the diaphragm-like apparatus in the genera Salpingacantha and Salpingella is not homologous to the foldable ones in the genera mentioned above is supported by molecular and cytological features. [source] An investigation of the cranial evolution of Asian pitvipers (Serpentes: Crotalinae), with comments on the phylogenetic position of Peltopelor macrolepisACTA ZOOLOGICA, Issue 4 2010Peng Guo Abstract Guo, P., Jadin, R.C., Malhotra, A. and Li, C. 2009. An investigation of the cranial evolution of Asian pitvipers (Serpentes: Crotalinae), with comments on the phylogenetic position of Peltopelor macrolepis,Acta Zoologica (Stockholm) 91: 402,407. We investigated the evolution of 12 cranial characters of 31 species of Asian pitvipers by examining the character state changes on a consensus tree modified from broadly consistent molecular results. We found that these characters appear stable with only one intraspecific polymorphism. Nine of the 12 characters form useful synapomorphies, whereas three are ambiguous and evolutionarily plastic. Clades that are supported with numerous apomorphies are the Trimeresurus group [consisting of the recently defined genera Trimeresurus sensuMalhotra and Thorpe (2004), Parias, Popeia, Viridovipera, Himalayophis, and Cryptelytrops] and the genera Protobothrops, Parias, and Viridovipera. Two species previously considered as congeners but now known to be distantly related, Ovophis monticola and ,Ovophis'okinavensis, have nearly identical character states, demonstrating substantial convergence in cranial characters. Finally, we attempt to infer the phylogenetic position of Peltopelor macrolepis by comparing its cranial features with that of other pitvipers. [source] The cranial morphology of Kayentachelys, an Early Jurassic cryptodire, and the early history of turtlesACTA ZOOLOGICA, Issue 3 2010Eugene S. Gaffney Abstract Gaffney, E.S. and Jenkins, F.A., Jr. 2010. The cranial morphology of Kayentachelys, an Early Jurassic cryptodire, and the early history of turtles. , Acta Zoologica (Stockholm) 91: 335,368 The skull morphology of Kayentachelys aprixGaffney et al., 1987, a turtle from the Early Jurassic Kayenta Fm of northern Arizona, demonstrates the presence of cryptodiran synapomorphies in agreement with Gaffney et al. (1987, 1991, 2007), and contrary to the conclusions of Sterli and Joyce (2007), Joyce (2007), Sterli (2008), and Anquetin et al. (2008). Specific characters found in Kayentachelys and diagnostic of cryptodires include the processus trochlearis oticum, the curved processus pterygoideus externus with a vertical plate, and the prefrontal,vomer contact, which are confirmed as absent in the outgroups, specifically the Late Triassic Proganochelys. The Joyce (2007) analysis suffers from the reduction of the signal from skull characters, with a consequently greater reliance on shell characters, resulting in pleurodires being resolved at various positions within the cryptodires. Kayentachelys reveals what a primitive cryptodire would be expected to look like: a combination of primitive and derived characters, with the fewer derived characters providing the best test of its relationships to other turtles. Although incompletely known, the Mid-Late Jurassic Condorchelys, Heckeremys, and Eileanchelys may be early cryptodires close to Kayentachelys. We confirm the Late Triassic Proterochersis as a pleurodire, dating the pleurodire,cryptodire split as Late Triassic or earlier. [source] Ultrastructure of spermatozoa of scolecophidian snakes (Lepidosauria, Squamata)ACTA ZOOLOGICA, Issue 3 2007L. Tavares-Bastos Abstract We provide a detailed description of the sperm ultrastructure of three species of scolecophidian snakes, Leptotyphlops koppesi (Leptotyphlopidae), Typhlops reticulatus (Typhlopidae) and Liotyphlops beui (Anomalepididae), and make comparisons with the spermatozoa of Ramphotyphlops waitii (Typhlopidae) (Harding et al. 1995). All the species studied bear synapomorphies of Squamata and Serpentes. Among scolecophidian snakes, we identified eight polymorphic characters. Previous analyses of molecular and somatic morphological data provide equivocal solutions to the relationships among Anomalepididae, Leptotyphlopidae and Typhlopidae. A close relationship between Anomalepididae and Typhlopidae is corroborated by two characters of sperm ultrastructure, presence of an electron-dense structure inside the proximal centriole and rounded mitochondria in transverse sections of T. reticulatus, Li. beui and R. waitii, whereas the absence of the ridge on the acrosome surface of Le. koppesi and T. reticulatus support a closer relationship between Typhlopidae and Leptotyphlopidae. The differences observed in sperm ultrastructure within Typhlopidae suggest the existence of snake intrafamilial polymorphism. The sperm characters of blindsnakes contain significant phylogenetic information and may provide important data for snake phylogenetic reconstructions. [source] The ultrastructure of the spermatozoa of Boa constrictor occidentalis, with considerations on its mating system and sperm competition theoriesACTA ZOOLOGICA, Issue 1 2006M. Tourmente Abstract Sperm ultrastructure has been described for several families of Squamata in which it has been considered a valuable character source for phylogenetic studies. However, sperm competition and mating systems have been demonstrated to influence variations in the sperm morphology and dynamics. The mating system of Boa constrictor occidentalis is likely to have a high degree of sperm competition. We investigated, for the first time, the ultrastructure of the spermatozoa of B. c. occidentalis and, thus, of the family Boidae. Active mating groups were captured from the field, and the spermatozoa of the males was collected by ejaculation and processed to obtain transmission electron micrographs and fluorescence micrographs. The spermatozoa are filiform and their morphology fits the general model described for snakes, and several synapomorphies belonging to the squamates can be identified in these cells. Nevertheless, the head is 25% longer and the midpiece presents a lower frequency of mitochondrial transformations than that of other snakes. We propose that this last trait, along with the extraordinary elongation of the midpiece and the system of multilaminar membranes covering this section (both synapomorphies of the snake spermatozoa), are adaptive responses to processes of sperm competition and sperm storage. [source] Patterns and consequences of vertebrate Emx gene duplicationsEVOLUTION AND DEVELOPMENT, Issue 4 2009Elizabeth M. Tank SUMMARY We have cloned and analyzed two Emx genes from the lamprey Petromyzon marinus and our findings provide insight into the patterns and developmental consequences of gene duplications during early vertebrate evolution. The Emx gene family presents an excellent case for addressing these issues as gnathostome vertebrates possess two or three Emx paralogs that are highly pleiotropic, functioning in or being expressed during the development of several vertebrate synapomorphies. Lampreys are the most primitive extant vertebrates and characterization of their development and genomic organization is critical for understanding vertebrate origins. We identified two Emx genes from P. marinus and analyzed their phylogeny and their embryological expression relative to other chordate Emx genes. Our phylogenetic analysis shows that the two lamprey Emx genes group independently from the gnathostome Emx1, Emx2, and Emx3 paralogy groups. Our expression analysis shows that the two lamprey Emx genes are expressed in distinct spatial and temporal patterns that together broadly encompass the combined sites of expression of all gnathostome Emx genes. Our data support a model wherein large-scale regulatory evolution of a single Emx gene occurred after the protochordate/vertebrate divergence, but before the vertebrate radiation. Both the lamprey and gnathostome lineages then underwent independent gene duplications followed by extensive paralog subfunctionalization. Emx subfunctionalization in the telencephalon is remarkably convergent and refines our understanding of lamprey forebrain patterning. We also identify lamprey-specific sites of expression that indicate either neofunctionalization in lampreys or sites-specific nonfunctionalization of all gnathostome Emx genes. Overall, we see only very limited correlation between Emx gene duplications and the acquisition of novel expression domains. [source] Taxonomy of Late Jurassic diplodocid sauropods from Tendaguru (Tanzania)FOSSIL RECORD-MITTEILUNGEN AUS DEM MUSEUM FUER NATURKUNDE, Issue 1 2009Kristian Remes Abstract The Late Jurassic (Tithonian) Tendaguru Beds of Tanzania yielded one of the richest sauropod faunas known, including the diplodocines Tornieria africana (Fraas, 1908) and Australodocus bohetii Remes, 2007, the only known representatives of their group on the southern continents. Historically, the holotypes and referred material of both taxa plus dozens of additional specimens had been subsumed under the term "Barosaurus africanus " (Fraas, 1908). Here, the taxonomic status of the referred elements is reviewed by evaluating the phylogenetic information content of their anatomical characters, in order to provide a firm footing for further studies (e.g. of morphometrics, histology, and phylogeny of the Tendaguru sauropods). Some of the material shows diplodocine synapomorphies and may belong to either Tornieria or Australodocus, while other specimens are diagnostic only on higher taxonomic levels (Diplodocidae, Flagellicaudata, or Diplodocoidea indet.). The isolated limb elements in most cases lack phylogenetically diagnostic characters. Generally, the "Barosaurus africanus " sample shows a substantial grade of morphological variation, and it cannot be ruled out that there are more flagellicaudatans represented in the Tendaguru material than the diplodocines and dicraeosaurids already known. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Phylogeny of the Cocculinoidea (Mollusca, Gastropoda)INVERTEBRATE BIOLOGY, Issue 2 2003Ellen E. Strong Abstract. The superfamily Cocculinoidea is a group of marine, deep-water, limpet-like gastropods. Recent speculation surrounding their affinities has concentrated on their placement within the Gastropoda. However, phylogenetic relationships within the Cocculinoidea, especially the monophyly of families and genera within the group, remain poorly understood. Phylogenetic analysis of 31 morphological characters for 15 cocculinoidean taxa and 2 outgroups resulted in a single most parsimonious tree, length=70, CI=0.62, and RI=0.71. Monophyly of the Cocculinoidea, Cocculinidae, and the genera Cocculina and Coccopigya was supported; Paracocculina and Coccocrater were found to be paraphyletic. Character optimization demonstrates that many characters often cited as diagnostic of various taxa, are often homoplastic and/or synapomorphies at different hierarchical levels. [source] Hand development and sequence of ossification in the forelimb of the European shrew Crocidura russula (Soricidae) and comparisons across therian mammalsJOURNAL OF ANATOMY, Issue 2 2004Jan Prochel Abstract Hand development in the European shrew Crocidura russula is described, based on the examination of a cleared and double-stained ontogenetic series and histological sections of a c. 20-day-old embryo and a neonate. In the embryo all carpal elements are still mesenchymal condensations, and there are three more elements than in the adult stage: the ,lunatum', which fuses with the scaphoid around birth; a centrale, which either fuses with another carpal element or just disappears later in ontogeny; and the anlage of an element that later fuses with the radius. Carpal arrangement in the neonate and the adult is the same. In order to compare the relative timing of the onset of ossification in forelimb bones in C. russula with that of other therians, we built up two matrices of events based on two sets of data and used the event-pair method. In the first analysis, ossification of forelimb elements in general was examined, including that of the humerus, radius, ulna, the first carpal and metacarpal to ossify, and the phalanges of the third digit. The second analysis included each carpal, humerus, radius, ulna, the first metacarpal and the first phalanx to ossify. Some characters (= event,pairs) provide synapomorphies for some clades examined. There have been some shifts in the timing of ossification apparently not caused by ecological and/or environmental influences. In two species (Oryctolagus and Myotis), there is a tendency to start the ossification of the carpals relatively earlier than in all other species examined, the sauropsid outgroups included. [source] The hyomandibulae of rhizodontids (Sarcopterygii, stem-tetrapoda)JOURNAL OF MORPHOLOGY, Issue 6 2008Martin D. Brazeau Abstract Despite its important role in the study of the evolution of tetrapods, the hyomandibular bone (the homologue of the stapes in crown-group tetrapods) is known for only a few of the fish-like members of the tetrapod stem-group. The best-known example, that of the tristichopterid Eusthenopteron, has been used as an exemplar of fish-like stem-tetrapod hyomandibula morphology, but in truth the conditions at the base of the tetrapod radiation remain obscure. We report, here, four hyomandibulae, from three separate localities, which are referable to the Rhizodontida, the most basal clade of stem-tetrapods. These specimens share a number of characteristics, and are appreciably different from the small number of hyomandibulae reported for other fish-like stem-tetrapods. While it is unclear if these characteristics represent synapomorphies or symplesiomorphies, they highlight the morphological diversity of hyomandibulae within the early evolution of the tetrapod total-group. Well-preserved muscle scarring on some of these hyomandibulae permit more robust inferences of hyoid arch musculature in stem-tetrapods. J. Morphol., 2008. © 2008 Wiley-Liss, Inc. [source] Ontogeny and homology of the claustra in Otophysan Ostariophysi (Teleostei)JOURNAL OF MORPHOLOGY, Issue 8 2006Ralf Britz Abstract We studied the ontogeny of the claustrum comparatively in representatives of all otophysan subgroups. The claustrum of cypriniforms has a cartilaginous precursor, the claustral cartilage, which subsequently ossifies perichondrally at its anterior face and develops an extensive lamina of membrane bone. The membrane bone component of the claustrum and its close association with the atrium sinus imparis, a perilymphatic space of the Weberian apparatus, are both synapomorphies of cypriniforms. The characiform claustrum is not preformed in cartilage and originates as a membrane bone ossification, a putative synapomorphy of that taxon. Among siluriforms, the claustrum is present only in more basal groups and originates as an elongate cartilage that ossifies in a characteristic ventrodorsal direction, possibly a synapomorphy of catfishes. Gymnotiforms lack the claustral cartilage and claustrum. We review all previous hypothesis of claustrum homology in light of the above findings and conclude that the most plausible hypothesis is the one originally proposed by Bloch ([1900] Jen Z Naturw 34:1,64) that claustra are homologs of the supradorsals of the first vertebra. J. Morphol. © 2006 Wiley-Liss, Inc. [source] 1 Taxon sampling and inferences about diatom phylogenyJOURNAL OF PHYCOLOGY, Issue 2003A. J. Alverson Proper taxon sampling is one of the greatest challenges to understanding phylogenetic relationships, perhaps as important as choice of optimality criterion or data type. This has been demonstrated in diatoms where centric diatoms may either be strongly supported as monophyletic or paraphyletic when analyzing SSU rDNA sequences using the same optimality criterion. The effect of ingroup and outgroup taxon sampling on relationships of diatoms is explored for diatoms as a whole and for the order Thalassiosirales. In the latter case, SSU rDNA and rbcL sequence data result in phylogenetic relationships that appear to be strongly incongruent with morphology and broadly incongruent with the fossil record. For example, Cyclotella stelligera Cleve & Grunow behaves like a rogue taxon, jumping from place to place throughout the tree. Morphological data place C. stelligera near the base of the freshwater group as sister to the extinct genus Mesodictyon Theriot and Bradbury, suggesting that it is an old, long branch that might be expected to "misbehave" in poorly sampled trees. Cyclotella stelligera and C. bodanica Grunow delimit the diameter of morphological diversity in Cyclotella, so increased sampling of intermediate taxa will be critical to resolving this part of the tree. Morphology is sampled for a much greater number of taxa and many transitional states of putative synapomorphies seem to suggest a robust morphological hypothesis. The Thalassiosirales are unstable with regards to taxon sampling in the genetic data, suggesting that perhaps the morphological hypothesis is (for now) preferable. [source] Bone histology of Silesaurus opolensisDzik, 2003 from the Late Triassic of PolandLETHAIA, Issue 2 2010UCJA FOSTOWICZ-FRELIK Fostowicz-Frelik, ,. & Sulej, T. 2009: Bone histology of Silesaurus opolensisDzik, 2003 from the Late Triassic of Poland. Lethaia, Vol. 43, pp. 137,148. The phylogenetic relationships of Silesaurus opolensis have been the subject of intense debate since its discovery. Silesaurus possesses some features characteristic of ornithischian dinosaurs, such as the presence of a beak at the front of the lower jaw, yet it lacks a number of important femoral and dental synapomorphies of Dinosauria. The microstructure of the long bones (femur, tibia and metatarsal) and ribs of this species reveals a relatively intensive rate of growth, comparable with that seen in small dinosaurs and the gracile crocodylomorph Terrestrisuchus. Cortical bone formed mainly by periosteal tissue with fibro-lamellar matrix (in older specimens parallel fibred) shows very little secondary remodelling and only in one specimen (large tibia ZPAL Ab III/1885) few lines of arrested growth are present in the outermost cortex. The vascularization is relatively dense, mainly longitudinal and ceases towards the periphery, forming almost avascular parallel fibred bone at the bone surface. This indicates maturation and significant decrease in the growth ratio in mature specimens of S. opolensis. The delicate trabeculae exhibit cores formed by the primary cancellous tissue lined with lamellar endosteal bone. The rather intense growth of S. opolensis implies a relatively high metabolic rate. Moreover, evidence from the fibro-lamellar tissue, predominant in the cortex, suggests that this kind of rapid bone deposition could be more typical of Archosauria than previously assumed, a prerequisite for the evolution of the very fast growth rates observed in large ornithischians, sauropods and large theropods. ,Archosauria, Bone histology, Dinosauriformes, Late Triassic, Silesaurus opolensis. [source] First-instar larval morphology in the subtribe Lydina (Coleoptera, Meloidae, Lyttini), with discussion on its systematic valueMITTEILUNGEN AUS DEM MUSEUM FUER NATURKUNDE IN BERLIN-DEUTSCHE ENTOMOLOGISCHE ZEITSCHRIFT, Issue 2 2006Federica Turco Abstract First-instar larvae of five species of Lydina, belonging to three genera , Lydus trimaculatus italicus Kaszab, L. europaeus Escherich, Oenas crassicornis (Illiger), O. tarsensis (Abeille de Perrin), and Alosimus chalybaeus (Tauscher) , are described, and new observations on two species previously described Oenas afer (Linnaeus) and Alosimus cirtanus (Lucas) are carried out. The larval morphology of Lydina, studied through light and scanning electron microscope and compared to that of other Lyttini genera, does not support the taxonomic value of the Lydina subtribe since no synapomorphies for this lineage are recognised. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Cladistic Analysis of A Problematic Ammonite Group: the Hamitidae (Cretaceous, Albian,turonian) and Proposals for New Cladistic TermsPALAEONTOLOGY, Issue 4 2002Neale MonksArticle first published online: 24 NOV 200 The Hamitidae are a family of mid,Cretaceous heteromorph ammonites including lineages leading to four other families. Problems are outlined in trying to describe the phylogeny of completely extinct groups such as these heteromorph ammonites using the existing cladistic terminology, which is largely concerned with extant taxa and their ancestors. To solve these problems, two new terms are proposed: ,crown groups and ,stem groups, which are equivalent to crown and stem groups in terms of the evolutionary history of a clade, but are not defined on the basis of extant taxa. Instead they are defined by the topology of the phylogenetic tree, the ,crown group being a clade defined by synapomorphies but which gave rise to no descendants. A ,stem group is a branch of a phylogenetic tree which comprises the immediate sister groups of a given ,crown group but is not itself a clade. Examples of these terms are described here with reference to the phylogeny of the Hamitidae and their descendants. The Hamitidae are paraphyletic and form ,stem groups to a number of ,crown groups, namely the Anisoceratidae, Baculitidae, Scaphitidae, and Turrilitidae. The definitions of the genera and subgenera are refined with respect to the type species and the clades within which they occur, and four new genera are described: Eohamites, Helicohamites, Sziveshamites, and Planohamites. [source] Phylogenetic study of benthic, spine-bearing prorocentroids, including Prorocentrum fukuyoi sp. nov.PHYCOLOGICAL RESEARCH, Issue 2 2007Shauna Murray SUMMARY Species of prorocentroid dinoflagellates are common in marine benthic sediment and epibenthic habitats, as well as in planktonic habitats. Marine planktonic prorocentroids typically possess a small spine in the apical region. In this study, we describe a new, potentially widely distributed benthic species of Prorocentrum, P. fukuyoi sp. nov., from tidal sand habitats in several sites in Australia and from central Japan. This species was found to possess an apical spine or flange and was sister species to P. emarginatum. We analyzed the phylogeny of the group including this new species, based on large subunit (LSU) rDNA sequences. The genus contained a high level of divergence in LSU rDNA, in some cases among sister taxa. P. fukuyoi and P. emarginatum were found to be most closely related to a clade of generally planktonic taxa. Several morphological features may constitute more informative synapomorphies than habitat in distinguishing clades of prorocentroid species. [source] The Phylogenetic Significance of Anthropoid Paranasal SinusesTHE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 11 2008James B. Rossie Abstract In this study, the phylogenetic significance of anthropoid paranasal sinus anatomy is explored. New information reported in recent years has precipitated new hypotheses of sinus homology and more than doubled the number of anthropoid genera for which confident assessments of sinus identity can be made. As a result, it is likely that the phylogenetic meaning of commonly cited characters such as the ethmoid and frontal sinuses will change. The traditional method of "character mapping" is employed to test hypotheses of sinus homology and to reconstruct the ancestral states for sinus characters in major anthropoid clades. Results show that most sinuses appear to be primitive retentions in anthropoids, with their absences in various genera representing losses. Accordingly, many of these sinuses are potential anthropoid synapomorphies. Anat Rec, 291:1485,1498, 2008. © 2008 Wiley-Liss, Inc. [source] Calling in wild silvery gibbons (Hylobates moloch) in Java (Indonesia): behavior, phylogeny, and conservationAMERICAN JOURNAL OF PRIMATOLOGY, Issue 1 2006Thomas Geissmann Abstract Hardly any behavioral data are available for the silvery gibbon (Hylobates moloch), an endangered primate that is endemic to the island of Java, Indonesia. We studied the singing behavior of the easternmost population of this species in the Dieng mountains, central Java, in 1998,1999. We aimed to document the timing of singing, quantify the amount of singing by the respective sexes, and explore the role of bioacoustics in density estimation. A total of 122 song bouts in at least 12 groups were monitored. No duet songs were heard. Most of the song bouts (91.5%) were female solo song bouts or female scream bouts. In contrast to an earlier study on the westernmost population of silvery gibbons, during which few if any male songs were heard, at least 8.5% of the song bouts in our study were male solo song bouts. They were significantly longer in duration than the female songs. All male song bouts uttered before dawn (0520 hr) were produced in a chorus fashion, with at least three individuals participating. Choruses occurred about once every 8.5 days, and lasted longer and occurred earlier than female solo song bouts. Most male songs (60%) started between 0355,0440 hr, when it was still dark. All female songs, in contrast, started after 0500 hr, and female singing activity peaked around 0600. Regular male singing, male chorusing, and regular predawn singing have not previously been reported for silvery gibbons. Similarly separated periods of male and female solo songs and the absence of duetting have been observed in Kloss's gibbons (H. klossii) on the Mentawai Islands, and may represent synapomorphies shared by both species. The pronounced individual-specific song characteristics of silvery gibbons allow accurate mapping of groups. The density of gibbons at our study site was established to be 1.9,3.7 groups/km2, corresponding to 6.7,13.1 individuals/km2. We reassess the suitability of gibbon songs as a means of estimating the density and size of gibbon populations, and discuss the proximate causes for the absence of duetting in silvery gibbons. Am. J. Primatol. 68:1,19, 2006. © 2006 Wiley-Liss, Inc. [source] New Species of Enantiornithes (Aves: Ornithothoraces) from the Qiaotou Formation in Northern Hebei, ChinaACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 2 2010Xuri WANG Abstract: We report on a new species of enantiornithine bird from the Lower Cretaceous Qiaotou Formation of northern Hebei, China. The new taxon, Shenqiornis mengi gen. et sp. nov., possesses several enantiornithine synapomorphies but is unique from other known species. The specimen has a well-preserved skull that reveals new information about enantiornithine cranial morphology. The new taxon possesses a large postorbital with a long tapering jugal process indicating that some enantiornithines may have had a fully diapsid skull, as in Confuciusornis. The tooth morphology of the specimen is unique and likely represents a previously unknown trophic specialization within Enantiornithes. [source] Petenaeaceae, a new angiosperm family in Huerteales with a distant relationship to Gerrardina (Gerrardinaceae)BOTANICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2010MAARTEN J. M. CHRISTENHUSZ fls Petenaea cordata (from northern Central America) was first described in Elaeocarpaceae and later placed in Tiliaceae, but most authors have been uncertain about its familial affinities. It was considered a taxon incertae sedis in the Angiosperm Phylogeny Group classification (APG III). A recent collection was made in Guatemala, and analysis of both rbcL and atpB in the large Soltis et al. angiosperm matrix, the most completely sampled study published to date, indicated a moderately supported relationship to Tapiscia (Tapisciaceae, the only member of the newly recognized order Huerteales in this matrix; 81% bootstrap support). We then conducted a more restricted analysis using the Bayer et al. rbcL/atpB matrix for Malvales supplemented with the other genera of Huerteales from published studies. Our results indicate a distant, weakly supported sister-group relationship to the African genus Gerrardina (Gerrardinaceae; Huerteales). After comparison of the characters cited in the literature and an examination of herbarium material of both genera, we could find no obvious synapomorphies for Gerrardina and Petenaea or any other relationship of the latter, and we therefore propose the new monogeneric family, Petenaeaceae. The polymorphic order Huerteales now comprises four small families: Dipentodontaceae, Gerrardinaceae, Petenaeaceae and Tapisciaceae. © 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2010, 164, 16,25. [source] Embryology of Hortonioideae and Monimioideae (Monimiaceae, Laurales): characteristics of the ,lower' monimioidsBOTANICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 2 2008YUKITOSHI KIMOTO We investigated the embryology of the ,lower' monimioids, i.e. Monimioideae (Monimia, Palmeria and Peumus) and Hortonioideae (Hortonia), which are poorly described embryologically. Our results show that, contrary to what has been reported in the literature, ,lower' monimioids show very little variation in their embryological characters. Comparisons with Mollinedioideae (a large derived subfamily in Monimiaceae) and other families in Laurales show that the ,lower' monimioids are relatively consistent in sharing predominantly isobilateral tetrads of microspores and megaspores, a non-specialized chalaza, and a mesotestal,endotestal seed coat (with tracheoidal cells of the meso- and endotesta). It is likely that, while the shared successive cytokinesis during meiosis of microspore mother cells supports the Monimiaceae,Hernandiaceae,Lauraceae clade obtained by molecular evidence, no synapomorphies exist to support a sister-group relationship of Monimiaceae with Hernandiaceae or Lauraceae. Instead, the lack of hypostase in ovules and/or young seeds, the lack of endosperm in mature seeds and the amoeboid tapetum in the anther are likely synapomorphies of Hernandiaceae and Lauraceae. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158, 228,241. [source] A Basal Titanosauriform from the Early Cretaceous of Guangxi, ChinaACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 4 2006MO Jinyou Abstract, Based on a partial postcranial skeleton collected from the Lower Cretaceous Napai Formation of Guangxi, China, we erect a new sauropod taxon, Fusuisaurus zhaoi gen. et sp. nov. The holotype specimen consists of the left ilium, left pubis, anterior caudals, most of the dorsal ribs and distal end of the left femur. Fusuisaurus zhaoi is diagnosed by a unique combination of character states among the known sauropods. It displays several synapomorphies of Titanosauriformes but lacks many derived features seen in other titanosauriforms, suggesting that the new taxon represents the basalmost known titanosauriform and providing new evidence that Titanosauriformes originated from Asia. A size comparison suggests that Fusuisaurus zhaoi is among the largest Early Cretaceous sauropods, providing an important addition to the Early Cretaceous Chinese sauropod diversity. [source] Weighted parsimony phylogeny of the family Characidae (Teleostei: Characiformes)CLADISTICS, Issue 6 2009J. Marcos Mirande The family Characidae, including more than 1000 species, lacks a phylogenetic diagnosis, with many of its genera currently considered as incertae sedis. The aims of the present study are to propose a phylogenetic diagnosis and to assess higher-level relationships of and within Characidae. In this regard, 360 morphological characters are studied for 160 species of Characidae and related families. Phylogenetic analyses under implied weighting and self-weighted optimization are presented, exploring a broad range of parameters. The analysis under self-weighted optimization is innovative for this size of matrices. Familial status of Serrasalmidae is supported, and Acestrorhynchidae and Cynodontidae are included in a monophyletic Characidae. Engraulisoma taeniatum is transferred from Characidae to Gasteropelecidae. Thus constituted, the monophyly of Characidae is supported by seven synapomorphies. A new subfamily, Heterocharacinae, is proposed, and the subfamilies Aphyocharacinae, Aphyoditeinae, Characinae, Gymnocharacinae, and Stevardiinae are redefined. The Glandulocaudinae are included in Stevardiinae together with remaining members of "clade A" (sensuMalabarba and Weitzman, 2003. Comun. Mus. Ciênc. Tecnol. PUCRS, Sér. Zool. 16, 67,151.) and the genera Aulixidens and Nantis. Most incertae sedis genera are assigned, at least tentatively, to a phylogenetically diagnosed clade. [source] Phylogenetic relationships of the spider family Tetragnathidae (Araneae, Araneoidea) based on morphological and DNA sequence dataCLADISTICS, Issue 2 2009Fernando Álvarez-Padilla The monophyly of Tetragnathidae including the species composition of the family (e.g., Are Nephila and their relatives part of this lineage?), the phylogenetic relationships of its various lineages, and the exact placement of Tetragnathidae within Araneoidea have been three recalcitrant problems in spider systematics. Most studies on tetragnathid phylogeny have focused on morphological and behavioral data, but little molecular work has been published to date. To address these issues we combine previous morphological and behavioral data with novel molecular data including nuclear ribosomal RNA genes 18S and 28S, mitochondrial ribosomal RNA genes 12S and 16S and protein-coding genes from the mitochondrion [cytochrome c oxidase subunit I (COI)] and from the nucleus (histone H3), totaling ca. 6.3 kb of sequence data per taxon. These data were analyzed using direct optimization and static homology using both parsimony and Bayesian methods. Our results indicate monophyly of Tetragnathidae, Tetragnathinae, Leucauginae, the "Nanometa clade" and the subfamily Metainae, which, with the exception of the later subfamily, received high nodal support. Morphological synapomorphies that support these clades are also discussed. The position of tetragnathids with respect to the rest of the araneoid spiders remains largely unresolved but tetragnathids and nephilids were never recovered as sister taxa. The combined dataset suggests that Nephilidae is sister to Araneidae; furthermore, the sister group of Nephila is the clade composed by Herennia plus Nephilengys and this pattern has clear implications for understanding the comparative biology of the group. Tetragnathidae is most likely sister to some members of the "reduced piriform clade" and nephilids constitute the most-basal lineage of araneids. [source] The molecular phylogeny of the Miarus campanulae (Coleoptera: Curculionidae) species group inferred from CO1 and ITS2 sequencesCLADISTICS, Issue 3 2006Varpu Vahtera Miarus is a Holarctic weevil genus with morphologically very similar species, all breeding on Campanula plants or their close relatives. Two European members of this genus, Miarus campanulae (L.), the type species, and Miarus graminis (Bohemann) have recently been split into several new species on the basis of slight external variations. The separation of these new forms has proved impossible and new data was needed. Molecular data were gathered from specimens from a number of locations in Finland, Estonia, Denmark and Sweden. The regions sequenced were mitochondrial CO1 and nuclear ITS2. Both combined and separate datasets were analyzed using the optimization alignment program POY, with parsimony as the optimality criterion. The recently separated Miarus species was found to be indistinguishable from the traditionally recognized form on the basis of this sequence data. On the other hand, the traditionally recognized species were characterized by numerous synapomorphies. Our data suggest that recent studies have underestimated the morphological variation in this genus. We propose that this may also be true for many taxonomically problematic beetle complexes in well-studied European regions. The idea that molecular evidence will inevitably reveal unnoticed cryptic variation may only apply to poorly known regions. Miarus fennicusKangas, 1978 is placed as a junior synonym of Miarus campanulae (Linnaeus, 1767) syn. nov. © The Willi Hennig Society 2006. [source] Phylogeny of the Eucoilinae (Hymenoptera: Cynipoidea: Figitidae)CLADISTICS, Issue 2 2002F.M. Fontal-Cazalla The Eucoilinae are a diverse and important group of parasitoids of Diptera, particularly in the tropics, but they are poorly known systematically and their generic classification is partly chaotic. Here, we present the first comprehensive cladistic analysis of higher eucoiline relationships. The analysis is based on 148 skeletal characters of adults documented in more than 1100 digital images available in an Internet-accessible database. The characters were coded for 45 taxa representing 35 eucoiline genera, spanning the entire diversity of the group, and 7 outgroup genera. Relationships were partly difficult to resolve and parsimony analysis under implied weights performed considerably better than analysis under uniform weights. The results support the monophyly of the Eucoilinae and show that eucoilines are most closely related to the figitid subfamilies Emargininae and Pycnostigminae, but are ambiguous concerning the exact relationships among these three lineages. Of the 6 eucoiline genus groups recognized by Nordlander in 1982 (Entomol. Scand. 13, 269,292), only 2 are supported as monophyletic: the Trybliographa and Kleidotoma groups. The Gronotoma group is a paraphyletic assemblage of two different basal clades of eucoilines. The Rhoptromeris group is unnatural and only the 2 core genera, Rhoptromeris and Trichoplasta, form a monophyletic lineage. The data are ambiguous concerning the Ganaspis group, which appears to be paraphyletic, and the Chrestosema group, which may be a good clade. Based on the results we propose a modified system of informal genus groups in the Eucoilinae and discuss putative synapomorphies supporting each genus group. The proposed relationships imply that the first eucoilines were parasitoids of leaf-mining agromyzids. The earliest split in the group was apparently between an Afrotropical and a Neotropical lineage, and much of the early radiation of the group occurred in these regions, particularly in the Neotropics. [source] On the Other "Phylogenetic Systematics"CLADISTICS, Issue 3 2000Kevin C. Nixon De Queiroz and Gauthier, in a serial paper, argue that biological taxonomy is in a sad state, because taxonomists harbor "widely held belief" systems that are archaic and insufficient for modern classification, and that the bulk of practicing taxonomists are essentialists. Their paper argues for the scrapping of the current system of nomenclature, but fails to provide specific rules for the new "Phylogenetic Systematics",instead we have been presented with a vague and sketchy manifesto based upon the assertion that "clades are individuals" and therefore must be pointed at with proper names, rather than diagnosed by synapomorphies. They claim greater stability for "node pointing," yet even their own examples show that the opposite is true, and their node pointing system is only more stable in a purely metaphysical sense detached from characters, evidence, usage of names, and composition of groups. We will show that the node pointing system is actually far LESS stable than the existing Linnaean System when stability is measured by the rational method of determining the net change in taxa (species) included in a particular group under different classifications. [source] Phylogenetic Relationships of the Suborders of Coleoptera (Insecta)CLADISTICS, Issue 1 2000Rolf G. Beutel One hundred seven external and internal characters of larval and adult representatives of 28 genera of the coleopteran suborders were analyzed cladistically. Four groups of Neuropterida were introduced as outgroup. The analysis yielded 18 trees with a minimum of 194 steps (CI 0.691). All trees support the monophyly of all four suborders and a branching pattern (Archostemata + (Adephaga + (Myxophaga + Polyphaga))). The presence of elytra with meso- and metathoracic locking devices, the specific hind-wing folding, the close connection of exposed sclerites, the absence of the mera, the absence of eight thoracic muscles, the reduced abdominal sternite I, and the invagination of terminal segments are autapomorphies of Coleoptera. The monophyly of Coleoptera excl. Archostemata is supported by further transformations of the thoracic sclerites such as absence of the mesothoracic discriminal line and katepisternal joint, by an internalized or absent metathoracic trochantin, by the presence of a bending zone in the hind-wing, and by eight further muscle losses. Fusion of tibia and tarsus and presence of a single claw are larval synapomorphies of Myxophaga and Polyphaga. Adults are characterized by fusion of protrochantin and propleura and by the rigid connection of the meso- and metathoracic ventrites. The eucinetoid lineage of Polyphaga is characterized by the secondary absence of the bending zone of the alae. This results in a distinctly simplified wing folding mechanism. The monophyly of Cucujiformia (+ Bostrichoidea) is supported by the presence of cryptonephric Malpighian tubules. Transformations of fore-and hind-wings, reinforcement and simplification of the thoracic exoskeleton, and an efficient use of a distinctly reduced set of thoracic muscles play an important role in the early evolution of Coleoptera. Many different larval character transformations take place in the earlier Mesozoic within the suborders. [source] The braincase of the chondrichthyan Doliodus from the Lower Devonian Campbellton Formation of New Brunswick, CanadaACTA ZOOLOGICA, Issue 2009John Maisey Abstract The braincase of the late Lower Devonian (Emsian) chondrichthyan Doliodus is described for the first time. Its postorbital process is extended ventrally and probably enclosed part of the infraorbital sensory canal, as in some placoderms. Doliodus has a shark-like dentition, but its upper anterior tooth files were supported by the internasal cartilage of the braincase, not by the palatoquadrates. Modern selachian jaws and dentitions are not representative of primitive crown-group gnathostomes because they display a mixture of conserved and derived character states. Separation of the palatoquadrates by the internasal cartilage is probably a primitive condition for crown-group gnathostomes. Continuity of the upper dental arcade across the ethmoid region may represent a synapomorphy of chondrichthyans and some acanthodians (the condition is not found in placoderms or osteichthyans). Exclusion of the arcade from the ethmoid region is probably apomorphic within elasmobranchs. Doliodus has curious bar-like, paired subcranial ridges ending posteriorly at the hyomandibular articulation. These superficially resemble visceral arch infrapharyngohyals fused to the floor of the braincase, adding circumstantial palaeontological support to the old proposal that parts of visceral arches may be incorporated into the gnathostome braincase, although it seems more plausible that they formed in the lateral margins of the embryonic parachordal or hypotic lamina. [source] | |||||||||||||||||||||||||||||||