Introgressive hybridization erodes morphological divergence between lentic and lotic habitats in an endangered minnow

Pseudothilmanus Pic, 1918 is redescribed and two species, P. alatus Pic, 1918 and P. marginatus Pic, 1918, are placed in the genus. The subgenus Drilothilmanus Pic, 1918 is synonymized with the nominotypical genus on the basis of low morphological divergence and redundancy in classification. Pseudothilmanus is newly classified in the family Rhagophthalmidae, in contrast to the original placement in Drilidae. Diagnostic characters for Pseudothilmanus and both species placed within the genus are illustrated.

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Mastomys natalensis (Smith, 1834) as a natural host for Schistosoma haematobium (Bilharz, 1852) Weinland, 1858 x Schistosoma bovis Sonsino, 1876 introgressive hybrids

Parasitology Research ◽

10.1007/s00436-021-07099-7 ◽

2021 ◽

Author(s):

Boris A.E.S. Savassi ◽

Gauthier Dobigny ◽

Jonas R. Etougbétché ◽

Thalasse T. Avocegan ◽

François T. Quinsou ◽

...

Keyword(s):

Definitive Host ◽

Schistosoma Haematobium ◽

Rattus Rattus ◽

Introgressive Hybridization ◽

Mastomys Natalensis ◽

New Host ◽

Time Period ◽

Schistosoma Bovis ◽

Bulinus Globosus ◽

Internal Transcribed Spacer Rdna

AbstractCercarial emission of schistosomes is a determinant in the transmission to the definitive host and constitutes a good marker to identify which definitive host is responsible for transmission, mainly in introgressive hybridization situations. Our goal was to test the hypothesis that micro-mammals play a role in Schistosoma haematobium, S. bovis, and/or S. haematobium x S. bovis transmission. Small mammal sampling was conducted in seven semi-lacustrine villages of southern Benin. Among the 62 animals trapped, 50 individuals were investigated for Schistosoma adults and eggs: 37 Rattus rattus, 3 Rattus norvegicus, 9 Mastomys natalensis, and 1 Crocidura olivieri. Schistosoma adults were found in four R. rattus and two M. natalensis, with a local prevalence reaching 80% and 50%, respectively. Two cercarial chronotypes were found from Bulinus globosus experimentally infected with miracidia extracted from naturally infected M. natalensis: a late diurnal and nocturnal chronotype, and an early diurnal, late diurnal, and nocturnal chronotype. The cytochrome C oxidase subunit I mtDNA gene of the collected schistosomes (adults, miracidia, and cercariae) belonged to the S. bovis clade. Eleven internal transcribed spacer rDNA profiles were found; four belonged to S. bovis and seven to S. haematobium x S. bovis. These molecular results together with the observed multi-peak chronotypes add M. natalensis as a new host implicated in S. haematobium x S. bovis transmission. We discuss the origin of the new chronotypes which have become more complex with the appearance of several peaks in a 24-h day. We also discuss how the new populations of offspring may optimize intra-host ecological niche, host spectrum, and transmission time period.

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A uni- and multivariate analysis approach to reveal sexual size dimorphism in Iranian populations of Hypera postica (Coleoptera: Curculionidae)

Biologia ◽

10.1515/biolog-2015-0137 ◽

2015 ◽

Vol 70 (9) ◽

pp. 1228-1233 ◽

Cited By ~ 3

Author(s):

Ehsan Sanaei ◽

Marjan Seiedy ◽

Farzaneh Momtazi

Keyword(s):

Body Size ◽

Sexual Size Dimorphism ◽

Egg Laying ◽

Morphological Divergence ◽

High Fecundity ◽

Hypera Postica ◽

Size Dimorphism ◽

Female Body Size ◽

Divergence Pattern ◽

Iranian Populations

Abstract Body size dimorphism between genders is a commonly observed phenomenon in insects, usually manifested in larger female body size. Sexual Size Dimorphism (SSD) varies from species to species, the degree and direction influenced by certain evolutionary pressures. Intraspecific variation in SSD may also occur between populations. The Hypera postica (Gyllenhal, 1813) is a well-known alfalfa plant pest that shows a degree of morphological divergence in its populations. The female alfalfa weevils are very fecund and have a larger body size compared to males. To improve our knowledge on magnitude and direction of SSD in alfalfa weevil, we studied 200 specimens of H. postica from four Iranian populations (Karaj1, Karaj2, Tuyserkan and Jovein). 10 morphological variables from three external anatomic parts (pronotum, elytra and rostrum) and 45 ratio characters were statistically analyzed in order to determine the amount of SSD in Iranian populations. In addition we investigated for morphological divergence pattern in mentioned populations. The results of this study show that a low degree of morphological divergence occurs in Iranian populations. Measured variables indicate that the SSD pattern of H. postica is compatible with the Rensch’s rule, and is related to high fecundity of females and a lack of strong sexual selection. Also it is mentioned that the larger rostrum in females may correspond to its unique role in egg laying.

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No evidence for recent introgressive hybridization between the European and Siberian roe deer in Poland

Mammalian Biology ◽

10.1016/j.mambio.2019.04.008 ◽

2019 ◽

Vol 97 ◽

pp. 59-63

Author(s):

Magdalena Świsłocka ◽

Magdalena Czajkowska ◽

Maciej Matosiuk ◽

Alexander P. Saveljev ◽

Mirosław Ratkiewicz ◽

...

Keyword(s):

Roe Deer ◽

Introgressive Hybridization ◽

Siberian Roe Deer

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Effects of predation pressure and resource use on morphological divergence in omnivorous prey fish

BMC Evolutionary Biology ◽

10.1186/1471-2148-13-132 ◽

2013 ◽

Vol 13 (1) ◽

pp. 132 ◽

Cited By ~ 21

Author(s):

Kristin Scharnweber ◽

Kozo Watanabe ◽

Jari Syväranta ◽

Thomas Wanke ◽

Michael T Monaghan ◽

...

Keyword(s):

Resource Use ◽

Predation Pressure ◽

Morphological Divergence ◽

Prey Fish

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Morphological Divergence in Endemic Gastropods from Lake Tanganyika: Implications for Models of Species Flock Formation

Palaios ◽

10.2307/3514613 ◽

1987 ◽

Vol 2 (5) ◽

pp. 413 ◽

Cited By ~ 13

Author(s):

Mark R. Johnston ◽

Andrew S. Cohen

Keyword(s):

Lake Tanganyika ◽

Species Flock ◽

Morphological Divergence

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Adaptive radiation and hybridization in Wallace's Dreamponds: evidence from sailfin silversides in the Malili Lakes of Sulawesi

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2006.3558 ◽

2006 ◽

Vol 273 (1598) ◽

pp. 2209-2217 ◽

Cited By ~ 83

Author(s):

Fabian Herder ◽

Arne W Nolte ◽

Jobst Pfaender ◽

Julia Schwarzer ◽

Renny K Hadiaty ◽

...

Keyword(s):

New Species ◽

Adaptive Radiation ◽

Introgressive Hybridization ◽

Reticulate Evolution ◽

Species Group ◽

Potential Force ◽

Major Interest ◽

Key Factor ◽

Adaptive Radiations ◽

Malili Lakes

Adaptive radiations are extremely useful to understand factors driving speciation. A challenge in speciation research is to distinguish forces creating novelties and those relevant to divergence and adaptation. Recently, hybridization has regained major interest as a potential force leading to functional novelty and to the genesis of new species. Here, we show that introgressive hybridization is a prominent phenomenon in the radiation of sailfin silversides (Teleostei: Atheriniformes: Telmatherinidae) inhabiting the ancient Malili Lakes of Sulawesi, correlating conspicuously with patterns of increased diversity. We found the most diverse lacustrine species-group of the radiation to be heavily introgressed by genotypes originating from streams of the lake system, an effect that has masked the primary phylogenetic pattern of the flock. We conclude that hybridization could have acted as a key factor in the generation of the flock's spectacular diversity. To our knowledge, this is the first empirical evidence for massive reticulate evolution within a complex animal radiation.

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Mitochondrial phylogeography of baboons (Papiospp.) – Indication for introgressive hybridization?

BMC Evolutionary Biology ◽

10.1186/1471-2148-9-83 ◽

2009 ◽

Vol 9 (1) ◽

Cited By ~ 132

Author(s):

Dietmar Zinner ◽

Linn F Groeneveld ◽

Christina Keller ◽

Christian Roos

Keyword(s):

Phylogenetic Relationships ◽

Evolutionary History ◽

Introgressive Hybridization ◽

Distinct Species ◽

Eastern Africa ◽

East African ◽

Hamadryas Baboons ◽

Olive Baboons ◽

Initial Separation ◽

Molecular Studies

Abstract Background Baboons of the genus Papio are distributed over wide ranges of Africa and even colonized parts of the Arabian Peninsula. Traditionally, five phenotypically distinct species are recognized, but recent molecular studies were not able to resolve their phylogenetic relationships. Moreover, these studies revealed para- and polyphyletic (hereafter paraphyletic) mitochondrial clades for baboons from eastern Africa, and it was hypothesized that introgressive hybridization might have contributed substantially to their evolutionary history. To further elucidate the phylogenetic relationships among baboons, we extended earlier studies by analysing the complete mitochondrial cytochrome b gene and the 'Brown region' from 67 specimens collected at 53 sites, which represent all species and which cover most of the baboons' range. Results Based on phylogenetic tree reconstructions seven well supported major haplogroups were detected, which reflect geographic populations and discordance between mitochondrial phylogeny and baboon morphology. Our divergence age estimates indicate an initial separation into southern and northern baboon clades 2.09 (1.54–2.71) million years ago (mya). We found deep divergences between haplogroups within several species (~2 mya, northern and southern yellow baboons, western and eastern olive baboons and northern and southern chacma baboons), but also recent divergence ages among species (< 0.7 mya, yellow, olive and hamadryas baboons in eastern Africa). Conclusion Our study confirms earlier findings for eastern Africa, but shows that baboon species from other parts of the continent are also mitochondrially paraphyletic. The phylogenetic patterns suggest a complex evolutionary history with multiple phases of isolation and reconnection of populations. Most likely all these biogeographic events were triggered by multiple cycles of expansion and retreat of savannah biomes during Pleistocene glacial and inter-glacial periods. During contact phases of populations reticulate events (i.e. introgressive hybridization) were highly likely, similar to ongoing hybridization, which is observed between East African baboon populations. Defining the extent of the introgressive hybridization will require further molecular studies that incorporate additional sampling sites and nuclear loci.

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