Search results for "evolution"

Otolith-based age and growth of the Lessepsian species Fistularia commersonii (Osteichtyes: Fistulariidae) in South of Sicily (Central Mediterranean …

2016

During spring–summer 2013, 23 specimens of the Lessepsian Fistularia commersonii Rüppell, 1838 were studied through occasional catches by artisanal and coastal trawler fisheries in the South of Sicily (Mediterranean Sea). The total lengths (TL, cm, without filament) and weight (W, g) ranged between 69.0 and 104.0 cm and 155 and 798 g, respectively. The estimated sex-combined parameters of the length–weight relationship (k = 9*10–9; b = 3.6) suggested a positive allometry. All pairs of sagittae were examined under a stereomicroscope and the age estimated by counting the complete translucent zones, both as whole and thin sections, with ages from 3 to 5 years. Growth parameters (von Bertalanff…

Das phylogenetische System

2003

Arten konnen im Lauf der Zeit als Linien aufgefast werden, die durch Aufspaltungsereignisse gegeneinander abgegrenzt sind. Anhand der Abfolge solcher Aufspaltungen lassen sich Arten in einem hierarchischen System, dem phylogenetischen System, zusammenfassen. Nachfolgend werden wir uns zunachst mit dieser Hierarchie der Arten und ihren Einheiten befassen. Dann werden wir uns naher mit dem Gedanken zur Artbildung durch Hybridisierung auseinandersetzen, weil er die konsequ ent hierarchische Struktur des phylogenetischen Systems in Frage stellt.

Urania sloanus (Cramer, 1779) (Lepidoptera: Uraniidae), an Enigmatic Extinct Species in Polish Museum Collections

2019

Urania sloanus is an endemic species in Jamaica. The species probably became extinct at the end of the 19th century or the beginning of the 20th century. During the work on combining the collections of exotic butterflies in the Upper Silesian Museum in Bytom, one specimen of this taxon was found. The discovery of this species in the Museum of Upper Silesia in Bytom led us to search for entomological collections in other Polish museums. As a result of our search, we found three additional specimens: two specimens in the collection of the Museum of Natural History of the University of Wrocław and one at the Zoological Museum of the Polish Academy of Sciences in Warsaw. In total, in the Polish…

A revision of the new world species of Gymnoclasiopa Hendel (Diptera, Ephydridae)

2012

Species of the shore-fly genus Gymnoclasiopa Hendel from the New World are revised, including G. grecorum, sp. n. (Alaska. Juneau: Gastineau Channel, Thane Road (S Juneau; 58°16.9’N, 134°22.4’W)) and G. matanuska, sp. n. (Alaska. Matanuska-Susitna: Palmer (Matanuska River; 61°36.5’N, 149°04.1’W)). We also clarify the status of previously described species, including those now discovered to have Holarctic distributions and/or for which sexual dimorphism was not appreciated and the species was described twice, including G. montana (Cresson) as a syn. n. of G. bohemanni (Becker). Two species, G. bella (Mathis), comb. n., and G. chiapas (Mathis), comb. n., are transferred from Ditrichophora to …

Systematic Position of Gastropini (Diptera: Ephydridae), and a Review of Two Included Genera:GastropsWilliston andNotacanthinaMacquart

2017

The placement of the tribe Gastropini within the subfamily Gymnomyzinae, with the tribe Gymnomyzini as a sister-group, is supported. Validity for two genera Gastrops Williston and Notacanthina Macquart (senior synonym of Beckeriella Williston) is maintained. Particular characters of their proboscis, ventral receptacle and the male terminalia are presented. A key to species and habitus photographs of selected species of Gastrops and Notacanthina are provided. The following new combinations are proposed: Notacanthina clypeata (Lizarralde de Grosso, 1986), comb. nov., N. fasciata (Mathis & Grimaldi, 2000), comb. nov., N. filipina (Lizarralde de Grosso, 1994), comb. nov., N. gigas (Lizarralde d…

Technology generation to dissemination: lessons learned from the tef improvement project

2018

Indigenous crops also known as orphan crops are key contributors to food security, which is becoming increasingly vulnerable with the current trend of population growth and climate change. They have the major advantage that they fit well into the general socio-economic and ecological context of developing world agriculture. However, most indigenous crops did not benefit from the Green Revolution, which dramatically increased the yield of major crops such as wheat and rice. Here, we describe the Tef Improvement Project, which employs both conventional- and molecular-breeding techniques to improve tef—an orphan crop important to the food security in the Horn of Africa, a region of the world w…

Drastic Genome Reduction in an Herbivore's Pectinolytic Symbiont.

2017

Pectin, an integral component of the plant cell wall, is a recalcitrant substrate against enzymatic challenges by most animals. In characterizing the source of a leaf beetle’s (Cassida rubiginosa) pectin-degrading phenotype, we demonstrate its dependency on an extracellular bacterium housed in specialized organs connected to the foregut. Despite possessing the smallest genome (0.27 Mb) of any organism not subsisting within a host cell, the symbiont nonetheless retained a functional pectinolytic metabolism targeting the polysaccharide’s two most abundant classes: homogalacturonan and rhamnogalacturonan I. Comparative transcriptomics revealed pectinase expression to be enriched in the symbiot…

Resemblance of a model species and its mimic: Response to Bury and Cichoń

2018

An experimental assessment of reproductive isolation and its consequences for seasonal hybridization dynamics

2018

A century after introduction: variability in Cepaea hortensis (Müller, 1774) in Sibiu, central Romania

2019

AbstractThe polymorphic land snail Cepaea hortensis was introduced to the city of Sibiu, central Romania, in the first decade of the 20th century and has spread widely across the city. A total of 97 locations were examined in 2017 across the city to determine the habitat preferences and variation in shell size, shape, colour and banding polymorphism of C. hortensis, and to relate these to the same features in the likely source population from Mannheim, Germany, and the first established population in Sibiu. We found that C. hortensis was largely restricted to sites with some woody vegetation cover and showed a marked preference for abandoned and overgrown private gardens. Mean adult shell s…