A cytotaxonomic investigation of seven species in the Eusimulium vernum group (Diptera: Simuliidae)

1986 ◽  
Vol 64 (2) ◽  
pp. 296-311 ◽  
Author(s):  
Fiona F. Hunter ◽  
Victoria Connolly
Keyword(s):  
Sibling Species ◽  
North American ◽  
Banding Pattern ◽  
Polytene Chromosomes ◽  
The Other ◽  
Undescribed Species ◽  
Species Complexes

Using the banding pattern of Eusimulium vernum (Macquart) as a standard, the polytene chromosomes of seven North American members of the vernum group are described. These are Eusimulium aestivum (Davies, Peterson, and Wood), E. impar (Davies, Peterson, and Wood), E. gouldingi (Stone), E. croxtoni (Nickolson and Mickel), E. pugetense Dyar and Shannon, E. quebecense (Twinn), and an undescribed species provisionally designated Simulium sp. near furculatum/croxtoni. Two of these species, pugetense and quebecense, apparently are sibling species complexes. An inversion cladogram separates the seven species into two distinct lineages; aestivum, impar, pugetense, and quebecense belong to one and gouldingi, croxtoni, and Simulium sp. to the other.

Sibling species and sex chromosomes in Eusimulium vernum (Diptera: Simuliidae)

1985 ◽  
Vol 63 (9) ◽  
pp. 2145-2161 ◽  
Author(s):  
C. Brockhouse
Keyword(s):  
Sex Determination ◽  
Sibling Species ◽  
Sex Chromosomes ◽  
Polytene Chromosomes ◽  
Biological Species ◽  
Undescribed Species ◽  
Ecological Segregation ◽  
Sex Locus

The polytene chromosomes of larvae from samples of Eusimulium vernum, E. bicorne, and an undescribed species (designated here as Eusimulium "Yukon") were examined. Twelve cytotypes within E. vernum were distinguished, of which at least eight appear to be good biological species. These cytotypes, together with the two allied morphospecies, were related in a cytophylogeny. An ecological segregation between some of the siblings was observed. One cytotype apparently utilizes two (possibly three) separate chromosome (arms) in sex determination. Five of the total of six chromosome arms are involved in sex determination in the various members of this complex. The genetics of sex determination and the mechanisms of sex-locus shift are discussed in the context of these findings.

The polytene chromosomes of North American blackflies in the Eusimulium canonicolum group (Diptera: Simuliidae)

1984 ◽  
Vol 62 (10) ◽  
pp. 2097-2109 ◽  
Author(s):  
Victor I. Golini ◽  
Klaus Rothfels
Keyword(s):  
West Virginia ◽  
Polytene Chromosome ◽  
North American ◽  
Polytene Chromosomes ◽  
Undescribed Species ◽  
Cohesive Group ◽  
And Inversion

The polytene chromosomes of four taxa are described. These are (i) Eusimulium canonicolum Dyar and Shannon from four sites in Alberta; (ii) Eusimulium emarginatum (Davies, Peterson &Wood) from sites in Ontario, West Virginia, and Pennsylvania; (iii) Eusimulium euryadminiculum (Davies) with samples from Newfoundland, Ontario, Saskatchewan, and Alberta; and (iv) "Hinton," an undescribed species from western Alberta. These four taxa form a cytologically cohesive group, and they are characterized in terms of fixed inversion differences, sex differential segments, and inversion polymorphisms. Polytene chromosome idiograms and a cytophylogeny are presented. The morphologically related Eusimulium johannseni (Hart) is excluded on the grounds of its stronger chromosomal affiliation with the Eusimulium vernum group.

Divergent cytogenetic evolution in Nearctic and Palearctic populations of sibling species in Chironomus (Camptochironomus) Kieffer

1998 ◽  
Vol 76 (2) ◽  
pp. 361-376
Author(s):  
Iya I Kiknadze ◽  
Malcolm G Butler ◽  
Karlygash G Aimanova ◽  
Evgenya N Andreeva ◽  
Jon Martin ◽  
...  
Keyword(s):  
Sibling Species ◽  
Related Species ◽  
Polytene Chromosomes ◽  
Natural Populations ◽  
Chromosomal Polymorphism ◽  
The Other ◽  
Chironomus Tentans ◽  
Closely Related Species ◽  
Cytogenetic Evolution

Chromosomal polymorphism is described for natural populations of Chironomus pallidivittatus in both the Palearctic and Nearctic regions. The Palearctic populations studied exhibit 24 banding sequences, whereas 10 banding sequences have been recorded from Nearctic C. pallidivittatus. In total, 29 sequences and 37 genotypic combinations have been found. Of the 29 sequences known, only 5 are Holarctic (common to both the Nearctic and Palearctic), 19 are exclusively Palearctic, and 5 are Nearctic. The karyotype of Nearctic C. pallidivittatus is characterized by specific, homozygous Nearctic sequences in arms B and G and fixed Holarctic inversion sequences in the other arms. Only two chromosome arms in C. pallidivittatus, but all seven arms in the sibling species Chironomus tentans, differ between Palearctic and Nearctic forms by the presence of unique, homozygous sequences in the Nearctic karyotype. This indicates a great difference in the cytogenetic histories of these closely related species; much less karyotypic divergence between continents has occurred in C. pallidivittatus than in C. tentans. The cytogenetic distance between Palearctic and Nearctic populations of C. tentans is higher (DN = 1.62) than in C. pallidivittatus (DN = 0.27). Thus, Palearctic and Nearctic C. tentans should be regarded as sibling species, but Palearctic and NearcticC. pallidivittatus are best viewed as strongly divergent races of the same species. A photomap of polytene chromosomes of C. pallidivittatus is presented in which banding sequences are mapped by using C. tentans as a standard.

Intercontinental karyotypic differentiation of Chironomus entis Shobanov, a Holarctic member of the C. plumosus group (Diptera, Chironomidae)

Genome ◽  
2000 ◽  
Vol 43 (5) ◽  
pp. 857-873 ◽  
Author(s):  
Iya I Kiknadze ◽  
Malcolm G Butler ◽  
Veronica V Golygina ◽  
Jon Martin ◽  
Wolfgang F Wülker ◽  
...  
Keyword(s):  
Sibling Species ◽  
North American ◽  
New World ◽  
Polytene Chromosomes ◽  
Species Group ◽  
Homozygous State ◽  
Old World ◽  
The North ◽  
Chironomid Species ◽  
Order Of Magnitude

Analysis of banding sequences of polytene chromosomes in Palearctic (Russian) and Nearctic (North American) Chironomus entis shows strong karyotype divergence between populations on the two continents. Four out of seven chromosomal arms in the North American C. entis karyotype are characterized by sequences found only in the Nearctic. In total, 44 banding sequences are now known for this species across the Holarctic, including 22 exclusively Palearctic, 6 Holarctic, and 16 exclusively Nearctic sequences. The degree of cytogenetic differentiation between Palearctic and Nearctic C. entis populations is an order of magnitude greater than differentiation among populations within either continent, but is only one third as great as the cytogenetic distance between the sibling species C. entis and C. plumosus. C. entis is the only sibling species of C. plumosus uncovered during cytological identification of Chironomus species from more than 50 North American lakes, indicating that the plumosus sibling-species group is much smaller in the Nearctic than in the Palearctic, where a dozen sibling species are known. Cytogenetic distance values calculated between Nearctic and Palearctic representatives of both C. entis and its sibling species C. plumosus are similar, but result from different patterns of karyotype divergence. New World C. entis is distinguished from Old World populations by the 16 uniquely Nearctic sequences, four of which occur in the homozygous state. In contrast, North American C. plumosus has fewer uniquely Nearctic sequences, and only one that occurs as a homozygote. However, four chromosomal arms in C. plumosus that are polymorphic in the Palearctic show fixation, or near fixation, of Holarctic sequences in the Nearctic C. plumosus karyotype. Thus, both the fixation of Holarctic sequences, and the occurrence or fixation of distinctly Nearctic sequences, contribute significantly to karyotype divergence. Patterns of karyotype divergence in Palearctic and Nearctic populations of different Holarctic chironomid species are discussed relative to intercontinental cytogenetic differentiation in other dipterans.Key words: karyotype, inversion polymorphism, cytogenetic divergence, Chironomus.

Cytotaxonomy of the Simulium damnosum complex from central and northeastern Tanzania

Genome ◽  
1993 ◽  
Vol 36 (1) ◽  
pp. 112-130 ◽  
Author(s):  
William S. Procunier ◽  
Abraham I. S. Muro
Keyword(s):  
Sibling Species ◽  
Polytene Chromosomes ◽  
Malpighian Tubule ◽  
Taxonomic Status ◽  
Insect Vector ◽  
Simulium Damnosum ◽  
Species Complexes ◽  
Salivary Gland Polytene Chromosome ◽  
Larval Salivary Gland ◽  
Population Substructuring

A cytotaxonomic study of the medically important insect vector, Simulium damnosum s.l., revealed the presence of seven and possibly eight distinct taxa from central and northeastern Tanzania. Larval salivary gland polytene chromosome maps are presented for the first time for five cytotypes and one sibling species, which include the Nkusi form, the Sanje form, the Kisiwani form, Ketaketa C1 and C2, and the Kibwezi form. Inversion disequilibrium in males of the Kibwezi form indicate population substructuring is occurring and that this population may be in the early stages of speciation. Adults of the sibling species S. damnosum Kibwezi form and cytotype of the S. damnosum Nkusi form were identified using Malpighian tubule polytene chromosomes. The taxonomic status of the populations under study are discussed in relation to previously published papers and unpublished reports. Dimorphisms for centromere band enhancement occur on all three polytene chromosomes of the complement. The same centromere band can be polymorphic, sex linked, fixed, or lost in various cytotypes. In constructing a partial phylogeny, a hypothetical intermediate is proposed to account for the diverse fate of these centromere band dimorphisms and other inversion polymorphisms in different members of this nearly pan African complex. This pattern of chromosome restructuring is consistent with that seen for other species complexes within the Simuliidae.Key words: Simulium damnosum complex, Tanzania, cytotaxonomy, phylogenetics, and vector biology.

Geographic variation in the polytene chromosome banding pattern of the Holarctic midge Chironomus (Camptochironomus) tentans (Fabricius)

1996 ◽  
Vol 74 (1) ◽  
pp. 171-191 ◽  
Author(s):  
Iya I. Kiknadze ◽  
Karlygash G. Aimanova ◽  
Larissa I. Gunderina ◽  
Malcolm G. Butler ◽  
J. Kevin Cooper
Keyword(s):  
North America ◽  
Polytene Chromosome ◽  
Sibling Species ◽  
Banding Pattern ◽  
Cytogenetic Analysis ◽  
Western Europe ◽  
Chromosome Banding ◽  
Genetic Relationships ◽  
Polytene Chromosomes ◽  
European Populations

Polytene chromosomes of Chironomus (Camptochironomus) tentans from Europe, Siberia, and North America were examined to clarify genetic relationships among widely distributed populations of this Holarctic midge. This first extensive cytogenetic analysis of Siberian populations confirms earlier suppositions that C. tentans karyotypes are quite uniform across the Palearctic from western Europe to Yakutia. Greater differences exist among North American populations in Minnesota, Michigan, and Massachusetts, and as a group, these Nearctic populations share so few banding sequences with Palearctic C. tentans that recognition of discrete sibling species on each contintent is warranted. Photomaps of polytene chromosomes for both Palearctic and Nearctic sibling species are presented, and banding sequences are described with standardized notation. In total, 42 inversion sequences were found in the 18 Siberian populations examined, 15 of which were previously undescribed. Of the 19 sequences found in the three American populations studied, only 6 were shared with the Palearctic. Three of the seven chromosome arms in Nearctic C. tentans had no sequences in common with European populations and four shared none with Siberian populations.

scholarly journals Eurasian and North American phylogeny of Turolian hipparionine horses (Perissodactyla, Mammalia) in China

1992 ◽  
Vol 6 ◽  
pp. 305-305
Author(s):  
Mahito Watabe
Keyword(s):  
North America ◽  
North American ◽  
Northern China ◽  
Sensu Stricto ◽  
The Other ◽  
Dental Morphology ◽  
Facial Morphology ◽  
Open Land ◽  
Specialized Form ◽  
Eastern Half

The late Miocene Chinese hipparions are morphologically diversified showing similarity to both western Old World's and North American forms. Two Chinese taxa that are phylogenetically related to western Old World's forms are Hipparion fossatum (= H. forstende) from Baode (Shanxi) and H. hippidiodus from Qingyang (Gansu) and Baode. The former is related to H. mediterraneum and the latter to H. urmiense - platygenys from the Turolian localities in the western Old World. H. fossatum and H. hippidiodus are associated with the “dorcadoides” (open-land) and “mixed” faunas in northern China. Hipparion fossatum that is characterized by POF located close to the orbit co-occurs with large and morphologically specialized form, H. dermatorhinum in Baode (Loc.30). H. hippidiodus with reduced POF is discovered with smaller H. coelophyes in Loc. 43, 44 (Baode) and Loc. 115 (Gansu).The hipparions associated with the “gaudryi” (forest) fauna are characterized by well defined and small POF located far from the orbit. Those forms are: H. platyodus from Loc. 70; H. ptychodus from Loc. 73; H. tylodus from Hsi-Liang in Yushe - Wuxiang basins; and H. sefvei from Loc. 12 at Xin-an in Henan province. H. coelophyes from Baode (Loc.43 & 44) and Qingyang (Loc. 115) also show similar facial morphology to the these forms, although it has small size and shallow POF. Those forms are similar in facial and dental morphology to Hipparion sensu stricto and some species of Cormohipparion in North America.The assemblages of Chinese hipparions are composed of two groups whose members are phylogenetically similar to the forms from both western part of Eurasia and North America. The “gaudryi” fauna is considered younger than the other two on the basis of faunal analyses. The similarity in hipparionine taxonomy between northern China and North America in the latest Miocene is an evidences for possible faunal interchange(s) occurred during that period, as suggested by taxonomic analyses on carnivores and proboscideans in eastern half of Eurasia and North America.

Tunes That Bind: Paul J. Seelig, Eva Gauthier, Charles T. Griffes, and the Javanese Other

2009 ◽  
Vol 3 (2) ◽  
pp. 129-154
Author(s):  
HENRY SPILLER
Keyword(s):  
Identity Formation ◽  
North American ◽  
Raw Materials ◽  
Sense Of Self ◽  
The Other ◽  
Edward Said ◽  
Complex Relationship ◽  
East Indies ◽  
Dutch East Indies

AbstractThe powerful concept of orientalism has undergone considerable refinement since Edward Said popularized the term with his eponymous book in 1978. Orientalism typically is presented as a totalizing process that creates polar oppositions between a dominating West and a subordinate East. U.S. orientalisms, however, reflect uniquely North American approaches to identity formation that include assimilating characteristics usually associated with the Other. This article explores the complex relationship among three individuals—U.S. composer Charles T. Griffes, Canadian singer Eva Gauthier, and German-trained Dutch East Indies composer Paul J. Seelig—and how they exploited the same Javanese songs to lend legitimacy to their individual artistic projects. A comparison of Griffes's and Seelig's settings of a West Javanese tune (“Kinanti”) provides an especially clear example of how contrasting approaches manifest different orientalisms. Whereas Griffes accompanied the melody with stock orientalist gestures to express his own fascination with the exotic, Seelig used chromatic harmonies and a chorale-like texture to ground the melody in the familiar, translating rather than representing its Otherness. The tunes that bind Griffes, Gauthier, and Seelig are only the raw materials from which they created their own unique orientalisms, each with its own sense of self and its own Javanese others.

Speciation of cestoda. Evidence for two sibling species in the complex Bothrimonus nylandicus (Schneider 1902) (Cestoda: Cyathocephalidea)

Parasitology ◽  
1988 ◽  
Vol 97 (1) ◽  
pp. 139-147 ◽  
Author(s):  
F. Renaud ◽  
C. Gabrion
Keyword(s):  
Sibling Species ◽  
Definitive Host ◽  
Parasite Species ◽  
Adult Stage ◽  
Life Cycles ◽  
The Other ◽  
Congeneric Species ◽  
Biochemical Genetic ◽  
Autumn And Winter ◽  
Biological Differences

SUMMARYUsing biochemical genetic methods, we have distinguished 2 sibling species in the complex Bothrimonus nylandicus (Schneider, 1902), which infest 2 congeneric species of sole (Solea lascaris and Solea impar) on European coasts (Atlantic and Mediterranean). Neither of the parasite species is specific for either of the sole species, but one of them is present all year round, whereas the other is absent in the autumn and winter and only appears in the spring, subsequently disappearing at the end of the summer. Only S. impar lives in the Mediterranean, and is equally infested by both cestodes, whereas both species occur in the Atlantic and each of them is preferentially infested by 1 species of cestode. The shortness of the adult stage of the parasite in the definitive host and the presence of 2 life-cycles associated with competition between the 2 hosts in the Atlantic could be responsible for the biological differences observed and for maintaining the sibling species in sympatry.

Sign in / Sign up

Export Citation Format

Share Document