The "Uniramia" do not exist: the ground plan of the Pterygota as revealed by Permian Diaphanopterodea from Russia (Insecta: Paleodictyopteroidea)

1992 ◽  
Vol 70 (2) ◽  
pp. 236-255 ◽  
Author(s):  
Jarmila Kukalová-Peck
Keyword(s):  
Plant Community ◽  
Flapping Flight ◽  
Lower Permian ◽  
Selective Agent ◽  
Ural Mountains ◽  
Ground Plan ◽  
Selection For ◽  
Thoracic Legs ◽  
Maxillary Palps ◽  
Present Plant

The paleomorphology of extinct Paleozoic Diaphanopterodea (Paleodictyopteroidea: Paleoptera) in exceptionally well-preserved Lower Permian Uralia (Parelmoidea) and Paruralia (Paruraliidae) from Tshekarda in the Ural Mountains, Russia, was used to identify the basic morphological components of the pterygote head, body, and genitalia, as follows: a 6-segmented head with sutures between the somites and between the cephalic terga and epicoxae; antennae 2 with four enlarged basal elements and a flagellum; mandibles (shown as fully homologous to the gnathobase of other arthropods) with a sliding anterior articulation; leglike maxillary palps, labial palps, abdominal leglets, and gonostyli, all starting with prefemur, bearing a fully articulated patella (as in spiders) and ending in double claws; polyramous thoracic legs (i.e., with several outer rami or exites) and a prefemur not associated, as it usually is, with the trochanter; a thoracic pleuron (wall support) formed from a flattened subcoxa; an abdominal pleuron clearly composed of three flattened leg segments: the subcoxa, coxa, and trochanter; and genitalia revealing their derivation from legs bearing coxal and trochanteral endites. It is suggested that the homoeotic mutant ophthalmoptera is a morphologically acceptable indication that the cephalic epicoxa surrounds the eye. The presence of several rami (exites) on the legs of primitive Paleozoic and modern Crustacea, Chelicerata, and Insecta shows that they share a polyramous arthropod leg; "biramy," as well as "uniramy," is always secondary and does not define higher arthropod taxa. The Atelocerata Heymons, 1901 (= Myriapoda + Hexapoda) is a natural taxon. "Uniramia" was a taxon based mainly on an erroneous "ground plan" of the arthropod leg and mandible, and should be completely dropped from use. In marine arthropods, one of the upper exites often convergently develops into a long swimming oar ramus, and the legs become functionally "biramous." A complex aquatic epicoxal oar ramus of the ancestral Atelocerata may be the only appendage suitably preadapted to become a protowing, modifiable by selection for flapping flight. Paleodictyopteroids with sucking rostra (about 50% of Paleozoic entomofauna) are probably the most important selective agent that initiated the change from the Paleozoic plant community into the present plant community.

Most Paleozoic Protorthoptera are ancestral hemipteroids: major wing braces as clues to a new phylogeny of Neoptera (Insecta)

1992 ◽  
Vol 70 (12) ◽  
pp. 2452-2473 ◽  
Author(s):  
Jarmila Kukalová-Peck ◽  
Carsten Brauckmann
Keyword(s):  
Sister Group ◽  
New Method ◽  
Cantabrian Mountains ◽  
Wing Vein ◽  
Ground Plan ◽  
Northwestern Spain ◽  
The Media ◽  
Thoracic Legs ◽  
Phylogenetic Scheme ◽  
Cross Vein

The enigmatic and artificial Protorthoptera is the largest Paleozoic order of Neoptera. Typical hemipteroid head characters (inflated clypeus, styletal mouthparts) are here reported for "Protorthoptera" fossils and linked with the basic venational braces of hemipteroid wings. The "order" is recognized as being mostly composed of extremely primitive hemipteroids. Two new Late Carboniferous gerarid wings are described: Osnogerarus trecwithiensis n.gen., n.sp. from the Westphalian D of Osnabrück, Germany, and Cantabrala gandli n.gen., n.sp. from the Lower Stephanian (Cantabrian) of the Cantabrian Mountains, northwestern Spain. Several ground-plan characters of hemipteroids are described: head with visible segmentation; polyramous thoracic legs bearing exites and with trochanter not fused to prefemur; ovipositor with cutting ridges; the medial wing vein is shown as not the complete media (= M), but only the media posterior (= MP); the arculus is diagnosed as a cross-vein turned into an important brace; two radial sectors (RA and RP) originate separately from the radial basivenale; and the anal brace is formed by AA1. The hemipteroid stem-assemblage comprised (i) the gerarid line (extinct) with a long MP–CuA fusion replacing the arculus (derived) and with a repeatedly forked CuP (primitive), and (ii) the paoliid line with an arculus (a convex mp–cua cross-vein) (primitive) and a simple CuP (derived). The paoliids are the probable ancestors of modern hemipteroids. The Hemiptera (Sternorrhycha + Auchenorrhyncha + Coleorrhyncha + Heteroptera) lost the ScA + vein to a V-shaped notch or a flexion line (synapomorphy). Geraridae, Paleozoic and Recent Insecta, and all Arthropoda have demonstrably polyramous legs in the ground plan. Use of the taxon "Uniramia" is erroneous in every aspect. A new method using major venational braces is offered to define the wings of all higher neopteran taxa and to resolve the uncertain relationships between some modern orders. Polyneoptera (plecopteroids + orthopteroids + blattoids) is a polyphyletic taxon, and should be abandoned. Blattoids are not directly related to orthopteroids, but are the sister-group of hemipteroids + endopterygotes. An updated basic phylogenetic scheme of Neoptera proposed here comprises the following clades: (Pleconeoptera (Orthoneoptera (Blattoneoptera (Hemineoptera + Endoneoptera)))).

Lower Permian "mecopteroid-like" insects from central Europe (Insecta, Endopterygota)

1990 ◽  
Vol 27 (3) ◽  
pp. 459-468 ◽  
Author(s):  
Jarmila Kukalova-Peck ◽  
Rainer Willmann
Keyword(s):  
New Species ◽  
Kuznetsk Basin ◽  
Phylogenetic Position ◽  
Lower Permian ◽  
Wing Venation ◽  
Medial Branch ◽  
New Genera ◽  
Ground Plan ◽  
The Family ◽  
The Media

Five new genera and eight new species of endopterygote insects are described from Lower Permian (Asselian and Artinskian) strata from Moravia, Czechoslovakia. Three of the genera belong to the family Protomeropidae: Pseudomerope n.gen. (including Pseudomerope mareki n.sp., Pseudomerope havlati n.sp., Pseudomerope oborana n.sp., Pseudomerope gallei n.sp.); Pseudomeropella n.gen. (including Pseudomeropella nekvasilovae n.sp.); and Stenomerope n.gen. (including Stenomerope spinari n.sp.). The fourth genus, Moravochorista n.gen. (including Moravochorista Carolina n.sp.), is similar to Pinnachorista and Kaltanochorista from the Lower Permian of the Kuznetsk Basin, USSR, but has not been assigned to a higher taxon. The phylogenetic position of both the Protomeropidae and Moravochorista and of their allies, within the endopterygotes is unclear. The fifth genus, Microptysmella n.gen. (including Microptysmella moravica n.sp.), may be the earliest known member of Amphiesmenoptera, since it exhibits almost the same wing venation as the amphiesmenopteran Microptysma sibiricum Martynova from the Lower Permian of the USSR.Wing-venation symbols homologous within the pterygote ground plan have been used in the descriptions. The vein "M5" of earlier authors is regarded as homologous to a convex cross-vein (strut) between the media posterior and the cubitus anterior, which is shared primitively by all endopterygotes, and is not a "fifth medial branch."

scholarly journals DIFFERENTIATION OF CLOSELY RELATED CELLS BY A VARIANT OF POLIOVIRUS, TYPE 2, MEF1 STRAIN

1959 ◽  
Vol 110 (4) ◽  
pp. 629-642 ◽  
Author(s):  
William H. Murphy ◽  
Raymond Armstrong
Keyword(s):  
Virus Infection ◽  
Hela Cells ◽  
Selective Agent ◽  
Poliovirus Type ◽  
Morphologic Response ◽  
Cell Strains ◽  
Selection For ◽  
The Stability ◽  
Cytopathogenic Effect

By application of a variant of poliovirus, Type 2, MEF1 strain, as a selective agent it was possible to distinguish among stable parent strains of epithelial cells and their clonal derivatives by their differential morphologic response to infection. The variant of poliovirus grew in a number of cell strains without induction of observable cytopathogenic changes. Other strains of cells reacted to viral infection by manifesting partial or complete degeneration. Parent HeLa cells and virus underwent simultaneous serial propagation in the absence of homotypic antiserum to virus. The stability of the virus-cell relationship was established by results from replicate experiments conducted over a period of years. Some cell strains of common origin maintained in different laboratories did not react similarly to the cytopathogenic effect of virus. Representative experiments revealed that the morphologic response of HeLa cells to MEF virus infection was not influenced by the presence or absence of pleuropneumonia-like organisms. The differential morphologic response of cells to infection was confirmed by efficiency-of-plating experiments which revealed differences in the capacity of MEF virus to form plaques in the test cell strains. Serial passages of MEF virus in cell strains demonstrated differences in their selection for cytopathogenic "mutants" of virus.

The wing venation and systematics of Lower Permian Diaphanopterodea from the Ural Mountains, Russia (Insecta: Paleoptera)

1992 ◽  
Vol 70 (2) ◽  
pp. 229-235 ◽  
Author(s):  
Jarmila Kukalová-Peck ◽  
Nina D. Sinichenkova
Keyword(s):  
Lower Permian ◽  
Wing Venation ◽  
Ural Mountains ◽  
Thoracic And Abdominal

Extinct Diaphanopterodea are described from the Lower Permian of Tshekarda, Urals, Russia: Parelmoidae: Uralia n.gen. (Uralia maculata n.sp. and Uralia sharovi n.sp.); Paruraliidae n.fam.: Paruralia n.gen. (Paruralia rohdendorfi n.sp. and Paruralia carpenteri n.sp.). Of all Paleozoic insects, the exceedingly well-preserved specimens of U. maculata have contributed the most important clues to the pterygote ground plans of the head, mouthparts, leg segmentation, thoracic and abdominal pleura, and genitalia.

scholarly journals Natural selection on floral morphology can be influenced by climate

2015 ◽  
Vol 282 (1808) ◽  
pp. 20150178 ◽  
Author(s):  
Diane R. Campbell ◽  
John M. Powers
Keyword(s):  
Natural Selection ◽  
Water Resources ◽  
Temporal Variation ◽  
Rocky Mountains ◽  
Floral Morphology ◽  
Floral Traits ◽  
Selective Agent ◽  
Pollination Success ◽  
Selection For ◽  
Colorado Rocky Mountains

Climate has the potential to influence evolution, but how it influences the strength or direction of natural selection is largely unknown. We quantified the strength of selection on four floral traits of the subalpine herb Ipomopsis sp. in 10 years that differed in precipitation, causing extreme temporal variation in the date of snowmelt in the Colorado Rocky Mountains. The chosen floral traits were under selection by hummingbird and hawkmoth pollinators, with hawkmoth abundance highly variable across years. Selection for flower length showed environmental sensitivity, with stronger selection in years with later snowmelt, as higher water resources can allow translation of pollination success into fitness based on seed production. Selection on corolla width also varied across years, favouring narrower corolla tubes in two unusual years with hawkmoths, and wider corollas in another late snowmelt year. Our results illustrate how changes in climate could alter natural selection even when the primary selective agent is not directly influenced.

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