Topic
Calathus
About: Calathus is a research topic. Over the lifetime, 42 publications have been published within this topic receiving 517 citations.
Papers
TL;DR: This study investigates the phylogeography of a group of carabid beetles from the genus Calathus on the Canary Islands and Madeira, located 450 km to the north of the Canaries and 650 km from the continent.
Abstract: The Canary Islands have proven to be an interesting archipelago for the phylogeographic study of colo- nization and diversification with a number of recent studies reporting evolutionary patterns and processes across a diversity of floral and faunal groups. The Canary Islands differ from the Hawaiian and Galapagos Islands by their close proximity to a continental land mass, being 110 km from the northwestern coast of Africa. This close proximity to a continent obviously increases the potential for colonization, and it can be expected that at the level of the genus some groups will be the result of more than one colonization. In this study we investigate the phylogeography of a group of carabid beetles from the genus Calathus on the Canary Islands and Madeira, located 450 km to the north of the Canaries and 650 km from the continent. The Calathus are well represented on these islands with a total of 29 species, and on the continent there are many more. Mitochondrial cytochrome oxidase I and II sequence data has been used to identify the phylogenetic relationships among the island species and a selection of continental species. Specific hypotheses of monophyly for the island fauna are tested with parametric bootstrap analysis. Data suggest that the Canary Islands have been colonized three times and Madeira twice. Four of these colonizations are of continental origin, but it is possible that one Madeiran clade may be monophyletic with a Canarian clade. The Calathus faunas of Tenerife and Madeira are recent in origin, similar to patterns previously reported for La Gomera, El Hierro, and Gran Canaria.
74 citations
TL;DR: The observed lower relative fitness of the short-winged morph in both cinctus and melanocephalus contradicts the supposed increase of the frequency of this morph in ageing, more or less isolated, populations of these species.
Abstract: In two successive years the fecundity of the carabid beetles Calathus (Neocalathus) cinctus, C. (N.) melanocephalus and C. (N.) mollis was studied in relation to wing-morph and temperature. Differences were found between the three species in both egg production and timing and length of the oviposition period. In all species the fecundity of laboratory bred beetles was significantly higher than that of females collected in the field. Long-winged females of both cinctus and melanocephalus had significantly higher egg production than short-winged females, and they also tended to produce eggs over a longer period. In mollis only the fecundity of the long-winged morph was established. The observed lower relative fitness of the short-winged morph in both cinctus and melanocephalus contradicts the supposed increase of the frequency of this morph in ageing, more or less isolated, populations of these species. The loss of long-winged genotypes, resulting from flight activities, is considered the most plausible cause of the increase of short-winged beetles in ageing populations. The higher fecundity of macropterous females makes them especially suited for (re)establishing populations.
55 citations
1 Jan 1972
48 citations
TL;DR: It is argued that the resulting differences in phenotypic plasticity of the long-winged genotype contribute to temporal and spatial differences in dispersal abilities between the two species.
Abstract: Aukema, B. 1990. Wing-length determination in two wing-dimorphic Calathus species (Coleoptera: Carabidae). — Hereditas 113: 189–202. Lund, Sweden. ISSN 0018–0661. Received September 3, 1990. Accepted September 18, 1990
Wing dimorphism in the carabid beetles Calathus cinctus and C. melanocephalus was studied by rearing offspring of single-pair crosses. In both species wing dimorphism was found to be determined genetically according to a single-locus model with brachyptery dominant to macroptery. In melanocephalus, however, the expression of the long-winged genotype is modified by environmental factors such as temperature and food supply, whereas in cinctus wing-length is independent of these factors. Moreover, in melanocephalus the expression of the long-winged genotype was found to be favoured by relatively better environmental conditions (higher temperatures and abundant food) and to be more frequent in females than in males, both in the field and in laboratory experiments. It is argued that the resulting differences in phenotypic plasticity of the long-winged genotype (none in cinctus and a varying amount in melanocephalus) contribute to temporal and spatial differences in dispersal abilities between the two species. The adaptive significance of the two types of inheritance is discussed.
27 citations
TL;DR: Results suggested that surface residues affected carabids, wolf spiders, and crickets in plots subjected to three successive years of an agronomic experiment on weed and water management.
Abstract: . This study examined how land management practices can affect the abundance of several arthropods commonly found in agriculture. This work was done in plots that had been subjected to three successive years of an agronomic experiment that evaluated the effects of a wheat, Triticum aestivum L., cover crop or no cover crop on weed and water management. After the third growing season, pitfall traps were installed and arthropods were collected and identified. At one location, carabids (Coleoptera: Carabidae) were identified to genus. Four of the genera (Amara, Anisodactylus, Harpalus, and Calathus) were more common under no-till conditions. Only one genus (Stenolophus) was more common in tilled plots. Five genera (Amara, Bradycellus, Scarites, Stenolophus, and Calathus) were more common in plots with a history of more weeds caused by less herbicide use. Carabids were not more abundant in plots with fewer weeds after herbicides had been applied. Past presence of a winter cover crop never reduced carab...
20 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2020 | 3 |
| 2015 | 1 |
| 2014 | 2 |
| 2012 | 2 |
| 2011 | 2 |
| 2010 | 2 |