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2. Altitudinal gradient in species richness and composition of dung beetles (Coleoptera: Scarabaeidae) in an eastern Euro-Mediterranean locality: functional, seasonal and habitat influences
- Creator:
- Şenyüz, Yakup , Lobo, Jorge M., and Dindar, Kemal
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Coleoptera, Scarabaeidae, Aphodiinae, dung beetles, species richness, historical factors, elevational turnover, seasonal variation, habitat, and Anatolia
- Language:
- English
- Description:
- The altitudinal gradient in diversity of dung beetles (Scarabaeidae) was studied in a Mediterranean mountain chain located in Central Anatolia to (i) determine if there are altitudinal differences between the main taxonomic groups, (ii) describe the seasonal variations in these assemblages and (iii) assess whether closed habitats influence dung beetle diversity differentially at different altitudes. Beetles were collected throughout a year at 14 localities between 469 and 1810 m above sea level in three different types of habitats. Dung beetle assemblages at 400 to 1200 m did not vary greatly in species richness, abundance and biomass. However, they varied in composition, with the assemblages dominated by species of Scarabaeinae up to 900 m, whereas in the mid-mountain assemblages (from 900 m to 1600 m) the numbers of species of Aphodiinae was higher. The decline with increase in altitude in richness, abundance and biomass of both small and large species of Scarabaeinae up to 1500 m, together with the constancy of these parameters in the case of Aphodiinae, accounts for the changes in the composition from the lowland to mid-mountain localities. Unlike at other Mediterranean localities, the open/closed structure of the habitat only slightly influences these assemblages independently of altitude or season. The general seasonal pattern follows the classical Mediterranean bimodal pattern associated with summer drought, but the patterns are more complex when the seasonal responses of the different groups and at different localities are analysed separately. We propose that the interplay between local climatic conditions (mainly temperature) and evolutionary conserved species preferences accounts for both the current seasonal and altitudinal gradients and the changes in species composition in terms of Aphodiinae and Scarabaeinae.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3. Cladistic analysis of Sericania (Coleoptera: Scarabaeidae: Sericini) - implications for the evolution of the xerophilous fauna of the Himalaya
- Creator:
- Ahrens, Dirk
- Type:
- article, model:article, and TEXT
- Subject:
- Coleoptera, Scarabaeidae, Sericini, Sericania, taxonomy, cladistic analysis, biogeography, Himalaya, and Tibet
- Language:
- English
- Description:
- A cladistic analysis of the species of Sericania Motschulsky, 1860, was executed using fifty-six morphological characters of adults. The monophyly of the genus is supported by the phylogenetic trees generated. Among the three major lineages indicated by the strict consensus tree the East Asian Sericania fuscolineata lineage represents the genus Sericania as defined "originally" and adopted by subsequent authors. The second, the clade Sericania nepalensis group + Sericania sp. 2, is a sister group to the S. fuscolineata clade. Both constitute a sister group to the third major lineage, the Sericania kashmirensis clade, which is endemic in the drier North-West Himalaya where it is the most diverse monophyletic group of Sericini. Provided that the stem species of the S. kashmirensis clade was xerophilous, the origin of this clade can not predate the early Miocene. Based on paleoclimatical and geological data, two competing hypotheses are proposed to explain the evolution of the xerophilous Sericania lineage: (a) a basal splitting within Sericania occurred because of the altitudinal and climatic barrier posed by the Himalaya, which separated the xerophilous lineage in the north (Tibet) from the hygrophilous lineage in the south-east (S slope of Himalaya/ Tibet), or (b) it was a consequence of the increase in the climatic east-west contrast along the southern slope of the Himalaya, which strengthened with the onset of monsoons 8 Ma ago.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
4. Does one size suit all? Dung pad size and ball production by Scarabaeus sacer (Coleoptera: Scarabaeidae: Scarabaeinae)
- Creator:
- Sullivan, Gregory T., Ozman-Sullivan, Sebahat K., Lumaret, Jean-Pierre, Zalucki, Myron P., and Baxter, Greg
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, brouci, vrubounovití, beetles, Scarabaeidae, Coleoptera, Scarabaeus sacer, ball roller, diel cycle, dung pad, intraspecies competition, nocturnal, seasonal, telecoprid, 2, and 59
- Language:
- English
- Description:
- Large, ball rolling dung beetles (Coleoptera: Scarabaeidae: Scarabaeinae) are competitively dominant and can strongly influence community succession in dung pads. Ball production by Scarabaeus sacer Linnaeus was recorded in the Kizilirmak Delta on the Black Sea coast of Turkey by using artificial dung pads from 125 g to 2,000 g. Utilisation of pads across the 16-fold range of pad sizes demonstrated behavioural variation that may reduce intraspecies competition. Ball production was highly concentrated, with 66 balls (61%) produced from 8 pads of the 3 largest pad sizes, which may be related to chemical attraction between males and females. Ball size increased with increasing pad size (P < 0.05) but the number of balls produced per 100 g of dung decreased with increasing pad size (P < 0.01). Pad size for maximum ball production and ball size were 1,371 g and 1,260 g, respectively. The highest and lowest percentage of dung used for ball production was 43% of 125 g pads and 13% of 2,000 g pads, respectively. Ball production and time of day were significantly related (P < 0.01); S. sacer was almost exclusively nocturnal, with 59% of all balls produced between 21.00 and 22.00. This optimum period for ball production early in the night may be a compromise between reduced risk of predation and the increased energy costs of ball production as the temperature falls., Gregory T. Sullivan, Sebahat K. Ozman-Sullivan, Jean-Pierre Lumaret, Myron P. Zalucki, Greg Baxter., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
5. Dung feeding in hydrophilid, geotrupid and scarabaeid beetles: Examples of parallel evolution
- Creator:
- Holter, Peter
- Type:
- article, model:article, and TEXT
- Subject:
- Dung beetles, Hydrophilidae, Geotrupidae, Scarabaeidae, feeding habits, particle feeding, mouthparts, and evolution
- Language:
- English
- Description:
- The maximum size of ingested ball-shaped particles was determined in three species of adult dung feeding beetle: Anoplotrupes (Geotrupes) stercorosus and Geotrupes spiniger (Geotrupidae, Geotrupinae) and Sphaeridium lunatum (Hydrophilidae, Sphaeridiinae). Maximum diameters were 40-65 µm, 60-75 µm and 16-19 µm in A. stercorosus, G. spiniger and S. lunatum, respectively, and it was concluded that these beetles feed in the same way as found in previous studies on coprophagous scarabaeids (Scarabaeinae and Aphodiinae). Coarse particles, mainly indigestible plant fragments, are rejected by an unknown filtering mechanism, and only very small particles are actually ingested. The two geotrupids, however, tolerate somewhat larger particles than do scarabaeines of similar size. This may reflect a lower degree of specialisation towards dung feeding in the geotrupids than in the scarabaeines. In several ways, the mouthparts of the coprophagous Scarabaeidae, Geotrupidae and Hydrophilidae show essentially the same morphological modifications that must be adaptations for dung feeding. For the hydrophilid (Sphaeridium), such modifications are described for the first time. They include asymmetric mandibular molars (right convex, left concave), fitting exactly into each other, with highly specialised surfaces that may concentrate the food prior to ingestion by squeezing fluid out of it. Other examples are the conjunctives (scarabaeids and geotrupids) or similar structures (the hydrophilid) and the large, hairy, pad-like distal lobes of the maxillar galeae. Provided that current views on the evolutionary history of these beetles are correct, dung feeding has arisen independently in the Scarabaeidae, Geotrupidae and Hydrophilidae. If so, the feeding on very small particles and the concomitant modifications of mouthparts in these three groups must be results of parallel evolution.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
6. Intrasexual fighting and mounting by females of the horned beetle Trypoxylus dichotomus (Coleoptera: Scarabaeidae)
- Creator:
- Iguchi, Yutaka
- Type:
- article, model:article, and TEXT
- Subject:
- Scarabaeidae, Trypoxylus dichotomus septentrionalis, horned beetle, female intrasexual fighting, female intrasexual mounting, and alternative tactic
- Language:
- English
- Description:
- Although females of the horned beetle, Trypoxylus dichotomus septentrionalis, have only small horns they often fight over access to feeding sites by head-butting each other. In addition, they sometimes show intrasexual mounting. In this study 82 females of different sizes were used to determine the relationship between fighting and mounting. Large females more often won fights and so gained access to food than small females. In contrast, small females more often mounted large females and then gained access to food than large females. These results suggest that female mounting may function as a tactic for reducing intrasexual fighting between small and large females.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
7. Larvae of Ataenius (Coleoptera: Scarabaeidae: Aphodiinae) :: Generic characteristics and species descriptions
- Creator:
- Verdú, José R. and Galante, Eduardo
- Type:
- article, model:article, and TEXT
- Subject:
- Scarabaeidae, Aphodiinae, Ataenius, larvae, description, key, dung beetles, turfgrass beetles, and taxonomy
- Language:
- English
- Description:
- We compared the larval morphology of the genera Ataenius and Aphodius. The third larval instars of five Ataenius species: Ataenius opatrinus Harold, A. picinus Harold, A. platenis (Blanchard), A. simulator Harold and A. strigicauda Bates, are described or redescribed and illustrated. The most important morphological characteristics of the larvae of Ataenius are found in the respiratory plate of thoracic spiracle, the setation of venter of the last abdominal segment, the setation of the epicranial region and the morphology of the epipharynx. A key to larvae of the known species of Ataenius is included.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
8. Larval morphology and biology of two species of Aphodius (Plagiogonus) from the Iberian Peninsula (Coleoptera: Scarabaeidae: Aphodiinae)
- Creator:
- Verdú, José R. and Galante, Eduardo
- Type:
- article, model:article, and TEXT
- Subject:
- Scarabaeidae, Aphodius, larvae, life history, morphology, and Iberian Peninsula
- Language:
- English
- Description:
- The larval morphology of Aphodius (Plagiogonus) nanus Fairmaire, 1860 and A. (P.) arenarius (Olivier, 1789) are described and redescribed, respectively. The common characters of both species, and the specific diagnostic characters are provided and discussed. The most important morphological characters of the larvae of Plagiogonus Mulsant, 1842 are the longitudinal alignment of the anterior setae of the stipes, the spatulate form of the posterior-lateral setae of the glossae of the hypopharynx, the slight development of the anal lobe slit, the form of the epitorma of the epipharynx, the slight sclerotization of the pternotormae and the relative length of second antennal segment. A key to the larvae of both species of Plagiogonus is presented along with life history data and the preferred food of these species. This study shows that A. arenarius and A. nanus feeding habits are closer to saprophagy than to coprophagy.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
9. Revision and hypothetical phylogenetic analysis of the species of the New World genus Ataeniopsis (Coleoptera: Aphodiinae: Eupariini)
- Creator:
- Stebnicka, Zdisława T.
- Type:
- article, model:article, and TEXT
- Subject:
- Coleoptera, Scarabaeidae, Aphodiinae, Eupariini, Ataeniopsis, new species, new combinations, taxonomy, phylogeny, distribution, and New World
- Language:
- English
- Description:
- The New World genus Ataeniopsis Petrovitz, 1973 is revised. Fifteen species are recognized including three new species: Ataeniopsis carupanoi sp. n. from Venezuela, A. jaltipani sp. n. from Mexico and A. vinacoensis sp. n. from Argentina. Lectotype of A. haroldi (Steinheil, 1872) is designated, the name of type species A. notabilis Petrovitz, 1973 is reestablished, five species are given in a new combination. The taxa are diagnosed, keyed and illustrated, and biological information and distribution data summarized following the species descriptions. A hypothetical phylogenetic analysis of Ataeniopsis based on cladistic analysis is presented.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
10. Size- and context-dependent nest-staying behaviour of males of the Japanese dung beetle, Copris acutidens (Coleoptera: Scarabaeidae)
- Creator:
- Akamine, Mayumi
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, brouci, vrubounovití, beetles, Scarabaeidae, Coleoptera, Copris acutidens, reproductive behaviour, male dimorphism, subsocial Scarabaeinae, post-copulatory processes, paternal provisioning, 2, and 59
- Language:
- English
- Description:
- Male dimorphism in insects is often accompanied by alternative mating tactics, which may, together with morphological traits, determine fitness of the different male morphs. Fitness consequences of male head horn size, male-male competition and male nest-staying behaviour were experimentally assessed in Copris acutidens, in which major and minor males can co-occur in nests. Possible differences in their reproductive behaviour and breeding success were assayed in a breeding experiment, in which females were paired with one major male, one minor male, or a pair of major and minor males. The advantage of major males staying in a nest along with a rival male is that major males are reproductively more successful than minor males in this species. The weight of dung transported into nests was significantly less in rearing containers containing two males than in those with a single male of either morph, although it did not differ between major and minor males when kept alone. The results indicate that the presence of a rival male negatively affects male provisioning due to interference from rival males. In contrast, in the present study, an increased incidence of male nest-staying behaviour was recorded in the two- male and one minor male treatment than in the one major male treatment. These results indicate that because of the risk of sperm competition, major males stay longer in nests if a rival male is present. Furthermore, minor males (which are subject to a higher risk of sperm competition) stay longer than major males in nests without a rival male. In other words, the present study revealed an alternative behaviour during the post-copulatory stage associated with horn dimorphism and the presence or absence of a rival male., Mayumi Akamine., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public