transformation series
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2021 ◽  
Vol 79 ◽  
pp. 189-204
Author(s):  
Diego N. Barbosa

Abstract A cladistic analysis based on 120 morphological characters and 72 OTUs was conducted for the flat wasp genus Anisepyris Kieffer. The genus is mainly Neotropical region with few Nearctic species. The analysis retrieved well-supported relationships among the Anisepyris species and exposed the distribution of synapomorphies among the lineages, particularly concerning the mandible shape, dorsal pronotal area sulcus, and mesopleural foveae. The main diagnostic characters, described by Barbosa and Azevedo (2018) for the 13 species-groups of Anisepyris, were scrutinized. Transformation series and evolutionary hypotheses were also discussed. This discussion elucidates the importance of each character in the evolution and diversification along the different lineages. A discussion on the species-groups distribution is proposed, in relation to their diagnostic features. A hypothesis about the original distribution and the subsequent diversifications was also discussed. In conclusion, due to a possible recent origin for Anisepyris species, the dispersion could be related primarily to dense forest areas; and the retrieved synapomorphies could be related to posterior distributions of the species in disparate areas from their original environment.


Author(s):  
Parin Jirapatrasilp ◽  
Piyoros Tongkerd ◽  
Ekgachai Jeratthitikul ◽  
Thor-Seng Liew ◽  
Arthit Pholyotha ◽  
...  

Abstract Members of the terrestrial snail family Dyakiidae from Southeast Asia show a distinct geographical distribution pattern and possess different degrees of complexity in their amatorial organ gland. This study is the first molecular phylogeny of ten of the 12 genera in this family, performed to provide insights into the origin of Dyakiidae and the evolution of their shells and amatorial organ gland structure. A new genus and new species, Pseudoquantula lenticularis Jirapatrasilp & Panha gen. & sp. nov., was uncovered based on its distinct morphological characters and molecular divergence. All other genera were retrieved as monophyletic except for Dyakia. Mainland Southeast Asia was inferred to be the ancestral range of the Dyakiidae, and the lineages then dispersed to and diversified in Borneo. Cladistic analysis showed that all 14 morphological characters used in this study were homoplastic. These results disagree with the previous amatorial organ transformation series, in which neither Pseudoplecta nor Quantula was ancestral to the other genera. The enigmatic genus Pseudoplecta, which lacks an amatorial organ gland, exhibited secondary loss.


2020 ◽  
Author(s):  
Pierre Gueriau ◽  
Štěpán Rak ◽  
Krzysztof Broda ◽  
Tomáš Kumpan ◽  
Tomáš Viktorýn ◽  
...  

AbstractWith over 15,000 extant species, Decapoda—or ten-legged crustaceans such as crabs, shrimp, lobsters, and relatives— are among the most speciose and economically important group of crustaceans. Despite of their diversity, anatomical disparity, and remarkable fossil record extending back to the Late Paleozoic, the origins of Decapoda and their phylogenetic relationships with eumalacostracans remains elusive and inconclusive. Molecular dating suggests that decapods originated in the Late Ordovician (~450 Mya), but no reliable fossil crown groups are found until the Late Devonian. Moreover, there is no consensus on which lineages belong to stem groups, obscuring our understanding of the roots of the ten-legged decapod body plans as a whole, and how they relate to other non-decapod crustaceans. We present new, exceptional fossils from the Late Devonian of Czech Republic and Poland that belong to †Angustidontida, an odd shrimp-looking crustacean with a combination of anatomical features unlike those of any crown eumalacostracan known—extinct or extant. Our phylogenetic analyses, including representatives of all major lineages of crown eumalacostracans plus †Angustidontida, identify angustidontids as the only known stem-group decapod, and give hints about the transformation series, polarity of change, and evolutionary pathways leading to the modern decapod body plans seen today.


2020 ◽  
Author(s):  
Nader Sakhaee ◽  
Yousef Fazaeli ◽  
Esmail Doustkhah ◽  
Sahar Sakhaee ◽  
Ahmad Takallou ◽  
...  

Base-catalyzed halogen dance reaction, has puzzled chemists ever since, to come up with new ideas regarding the mechanism of this beautiful chemical transformation. Series of fast metal-halogen exchanges are among the most recent mechanisms. Using DFT-Cam-B3LYP/ land2dz computations and focused on Halogen Dance (HD) reactions of bromobenzene derivatives, new bromo-bridged Transition States (TS) are proposed. These are then used to lay out 8 possible isomerization and 18 possible disproportionation paths. Mechanistic pathways were then analyzed based on TS’s energy and protonation/deprotonation steps to find the most suitable pathways. Overall pattern of these mechanisms draws for the first-time a cascade-like pattern for base-catalyzed halogen dance in its entirety. The present work shed light on a dynamic domino mechanism which dominates the realm of nonaqueous strongly basic medium reactions. Trends like these may well be a shared feature in base digestion of wood for its precious poly aromatic component like lignin.


2020 ◽  
Vol 10 (2) ◽  
pp. 28-31
Author(s):  
Natalia Smetankina ◽  
Oleksii Postnyi

A method for calculation of nonstationary thermal fields in a multilayer glazing of vehicles under the effect of impulse film heat sources is offered. The glazing is considered as a rectangular multilayer plate made up of isotropic layers with constant thickness. Film heat sources are arranged on layers' interfaces. The heat conduction equation is solved using the Laplace transformation, series expansion and the second expansion theorem. The method offered can be used for designing a safe multilayer glazing under operational and emergency thermal and force loading in vehicles.


IAWA Journal ◽  
2019 ◽  
Vol 40 (3) ◽  
pp. 488-529 ◽  
Author(s):  
Elisabeth A. Wheeler ◽  
Pieter Baas

ABSTRACTWe revisited questions about changes in the incidences of functional wood anatomical traits through geologic time and compared the incidences of these traits in the fossil record with modern wood anatomical diversity patterns in order to test classical (“Baileyan”) and more recent ecophyletic hypotheses of xylem evolution. We contrast patterns through time for tropical and higher (paleo)latitudes. Data are from the InsideWood database. There are striking differences between woods from high and mid latitudes versus tropical (paleo)-latitudes. At temperate and subtropical latitudes (Laurasia and high latitude Gondwana), the epoch by epoch time series supports the Baileyan transformation series of vessel-bearing woody angiosperms (basal woody angiosperms and eudicots): “primitive” features such as scalariform perforations, exclusively solitary vessels, apotracheal diffuse parenchyma and heterocellular rays abound in the Cretaceous and become much less frequent in the Cenozoic, especially post-Eocene. In contrast, in the paleotropics hardly any changes occur in the incidences – each epoch has an equally “modern” spectrum of wood anatomical attributes. Although climatic gradients from the poles to the equator were less steep in the Cretaceous than in the late Cenozoic, the wood anatomical differences between mid-high latitude woods and tropical woods were much more pronounced in the Cretaceous than in later epochs. This seeming paradox is discussed but we cannot resolve it.We suggest that tropical conditions have accelerated xylem evolution towards greater hydraulic efficiency (simple perforations), biological defense and hydraulic repair (elaborate paratracheal parenchyma patterns) as evidenced by late Cretaceous tropical latitude woods having near modern incidences of almost all traits. At higher paleolatitudes of both the Northern and Southern Hemisphere “ancestral” features such as scalariform perforations were retained in cooler and frost-prone regions where they were not selected against in mesic habitats because of lower demands on conductive efficiency, and could even be advantageous in trapping freeze-thaw embolisms. The fossil wood record remains too incomplete for testing hypotheses on the wood anatomy of the earliest angiosperms. The low incidence of so-called “xerophobic” woods sensu Feild with scalariform perforations with numerous (over 40) closely spaced bars in the Cretaceous tropical fossil record is puzzling. At higher paleolatitudes such woods are common in the Cretaceous.Ring porosity, an indicator of seasonal climates and deciduousness, occurs at low levels in the Cretaceous and Paleogene at higher paleolatitudes only, and reaches modern levels in the Miocene. In Neogene and Recent temperate Northern Hemisphere, wide vessels are virtually restricted to ring-porous woods. In the tropics, there is a low incidence of ring porosity throughout all epochs.The fossil record indicates that ecophysiological adaptation to tropical or temperate conditions was already evident in the Cretaceous with considerable latitudinal differences.


Zootaxa ◽  
2018 ◽  
Vol 4536 (1) ◽  
pp. 1
Author(s):  
KATSUYA KIMURA ◽  
HISASHI IMAMURA ◽  
TOSHIO KAWAI

The phylogenetic relationships of the families Cheilodactylidae and Latridae, plus related taxa, are examined from a detailed osteological perspective. The monophyly of each family is re-evaluated and a new classification is proposed on the basis of phylogenetic relationships. A phylogenetic analysis of characters in 67 transformation series showed Latridae to comprise a monophyletic group nested within cheilodactylids. Cheilodactylidae was non-monophyletic, but rather was formed by a clade including Cheilodactylus fasciatus and C. pixi having a sister relationship with a second clade comprising remaining cheilodactylids and latrids. A new classification is proposed, Cheilodactylidae, including only genus Cheilodactylus, and Latridae, including six genera (Latris, Nemadactylus, Mendosoma, Goniistius, Latridopsis and Dactylophora). 


Zootaxa ◽  
2017 ◽  
Vol 4221 (1) ◽  
pp. 1 ◽  
Author(s):  
KANAMI OKU ◽  
HISASHI IMAMURA ◽  
MAMORU YABE

 Phylogenetic relationships of the family Cyclopteridae were reconstructed based on osteological and external characters.  The monophyly of the family was strongly supported by 47 commonly recognized synapomorphies, including six autapomorphies (plus one additional autapomorphy, presence of a dorsal process on the pelvis, recognized after the phylogenetic analysis) among the suborder Cottoidei.  As a result of the cladistic analysis, a single most parsimonious phylogeny was obtained, based on characters in 32 transformation series.  A new classification of Cyclopteridae based on reconstructed relationships, including three subfamilies [Liparopsinae, Cyclopterinae and Eumicrotreminae (newly established)] and four genera (Aptocyclus, Cyclopsis, Cyclopterus and Eumicrotremus), is proposed.    


PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e2036 ◽  
Author(s):  
Graciela Piñeiro ◽  
Pablo Núñez Demarco ◽  
Melitta D. Meneghel

The hypotheses about the origin of the primitive amniotic tarsus are very speculative. Early studies argued that the origin of the astragalus, one of the largest proximal bones in the tarsus of basal amniotes, was produced by either the fusion of two, three, or even four of the original tarsal bones, the intermedium, the tibiale and the proximal centralia (c4 and c3), or that the intermedium alone transforms into the primitive astragalus. More recent studies have shown that the structure of the tarsus inCaptorhinussupports the former hypothesis about a fusion of the intermedium, the tibiale, the proximal centrale (c4) and eventually c3, producing a purportedly multipartite structure of the amniotic astragalus, but the issue remained contentious. Very well preserved tarsi of the Early Permian aquatic amnioteMesosaurus tenuidensGervais, 1864–1865, which represent the most complete ontogenetic succession known for a basal amniote (the other exceptional one is provided by the Late Permian diapsidHovasaurus bouleiPiveteau, 1926), suggest that there is more than one ossification center for the astragalus and that these fuse during late embryonic stages or maybe early after birth. A non-hatchedMesosaurusin an advanced stage of development shows that the tarsus is represented by a single bone, most probably the astragalus, which seems to be formed by the suturing of three bones, here interpreted as being the intermedium, the tibiale, probably already integrated to the c4 in an earlier stage of the development, and the c3. An amniote-like tarsal structure is observed in very basal Carboniferous and Permian tetrapods such asProterogyrinus, Gephyrostegus, the diadectidsDiadectesandOrobates, some microsaurs likeTuditanusandPantylusand possiblyWestlothiana, taxa that were all considered as true amniotes in their original descriptions. Therefore, the structure of the amniotic tarsus, including the configuration of the proximal series formed by the astragalus and the calcaneum, typically a pair of enlarged bones, could have been established well before the first recognized amniote walked on Earth. Accordingly, the tarsus of these taxa does not constitute specialized convergences that appeared in unrelated groups, they might be instead, part of a transformation series that involves taxa closely related to the early amniotes as some hypotheses have suggested.


2016 ◽  
Author(s):  
Graciela Piñeiro ◽  
Pablo Núñez Demarco ◽  
Melitta D Meneghel

The hypotheses about the origin of the primitive amniotic tarsus are very speculative. Early studies argued that the origin of the astragalus, one of the largest proximal bones in the tarsus of basal amniotes, was produced by either the fusion of two, three, or even four of the original tarsal bones, the intermedium, the tibiale and the proximal centralia (c4 and c3), or that the intermedium alone transforms into the primitive astragalus. More recent studies have shown that the structure of the tarsus in Captorhinus supports the former hypothesis about a fusion of the intermedium, the tibiale, the proximal centrale (c4) and eventually c3, producing a purportedly multipartite structure of the amniotic astragalus, but the issue remained contentious. Very well preserved tarsi of the Early Permian aquatic amniote Mesosaurus tenuidens Gervais, 1864-1865, which represent the most complete ontogenetic succession known for a basal amniote (the other exceptional one is provided by the Late Permian diapsid Hovasaurus boulei Piveteau, 1926), suggest that there is more than one ossification center for the astragalus and that these fuse during late embryonic stages or maybe early after birth. A non-hatched Mesosaurus in an advanced stage of development shows that the tarsus is represented by a single bone, most probably the astragalus, which seems to be formed by the suturing of three bones, which we interpret as being the intermedium, the tibiale, which could have already integrated the c4 in an earlier stage of the development, and the c3. An amniote-like tarsal structure is observed in very basal Carboniferous and Permian tetrapods such as Proterogyrinus, Gephyrostegus, the diadectids Diadectes and Orobates, some microsaurs like Tuditanus and Pantylus, and possibly Westlothiana, taxa that were all considered as true amniotes in their original descriptions. Therefore, the structure of the amniotic tarsus, including the configuration of the proximal series formed by the astragalus and the calcaneum, typically a pair of enlarged bones, could have been established well before the first recognized amniote walked on Earth. Accordingly, the tarsus of these taxa does not constitute specialized convergences that appeared in unrelated groups, they might be instead, part of a transformation series that involves taxa closely related to the early amniotes as some hypotheses have suggested.


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