Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 3

Liczba wyników na stronie
first rewind previous Strona / 1 next fast forward last
Wyniki wyszukiwania
Wyszukiwano:
w słowach kluczowych:  myrmecophily
help Sortuj według:

help Ogranicz wyniki do:
first rewind previous Strona / 1 next fast forward last
EN
We investigated the oviposition preferences of Phengaris alcon in relation to the height of the host plant (Gentiana pneumonanthe), the number of flowers, and the choice of microsite for oviposition (part of the host plant, height of oviposition) in a local population of this species in SW Slovenia at a depression of a seasonal lake Petelinje. P. alcon prefers the tallest (most conspicuous) host plants and plants with a larger number of flowers (i.e., more than 90% of all eggs were deposited on 12% of the tallest plants ≥ 30 cm), where eggs are deposited in the upper quarter of the plant height, usually on calyx (66.1%) and corolla (29.9%), and rarely on leaves or stems. Eggs are mostly deposited singly or in groups of two (> 50%) on a single plant, and eggs were found only on less than 3% of examined plants. Butterfly density was estimated at about 60 individuals per hectare. Obtained results indicate that preferences for oviposition sites are not random, and monitoring population density may provide important insight into the future population status of P. alcon.
EN
The ant species Lasius (Lasius) brunneus (Latr.) and L. (Dendrolasius) fuliginosus (Latr.) are known mutualists of the myrmecophilous giant tree aphids of the genus Stomaphis Walk. Species of the Lasius subgenus Chthonolasius Ruzs., which live cryptically underground, have not been considered regular mutualists of those aphids. They often nest close to the known mutualists with which they are through their mutual colony developments intimately interrelated – as temporary social parasites of L. brunneus or temporary hosts of L. fuliginosus. Such a constellation raises the question about contacts of L. (Chthonolasius) species with Stomaphis aphids. Here, we describe modes of interaction between L. (Chthonolasius) umbratus (Nyl.) and S. graffii Cholod. which is usually hosted by L. (L.) brunneus. Our field data from Poland and elsewhere in Europe, together with published information, support our view that also L. (Ch.) umbratus and other underground-living species of the subgenus Chthonolasius are true mutualists of Stomaphis which take care of the aphids. Such ants differ by their protective behaviour from ants which prey on or only exploit aphids. The co-occurrence of L. (Chthonolasius) species with Stomaphis aphids has hitherto been relatively rarely reported, which probably is due to the cryptic lifestyle of these ants. We discuss the complex interrelations among the above Lasius F. species which belong to separate levels of social parasitism, and their relations with Stomaphis aphids. We also suggest that L. (Chthonolasius) species, which in the socially-parasitic hierarchy are located between Lasius s. str. and L. (Dendrolasius), may serve as transmitters of Stomaphis aphids from the former to the latter species.
EN
Phengaris 'rebeli' Hirschke is a globally threatened obligatorily myrmecophilous and xerothermophilous butterfly. Caterpillars are initially endophytic and feed in flowerheads of Gentiana cruciata L. but they complete their development as social parasites of Myrmica Latr. ants. Relationships with hosts are specific and show geographical variation in Europe. Knowledge on them is vital for effective conservation. In Poland 'P. rebeli' was recorded from a dozen or so sites in the SE part of the country and from one locality in the Pieniny Mts. - a low calcareous mountain range on the Polish-Slovak border that constitutes a distinct geobotanical unit with specific climate and diversity of habitats. Present studies aimed to identify hostants of the butterfly in the Pieniny Mts. A total number of 30 Myrmica colonies were searched in 2008 near larval food plants bearing eggs of 'P. rebeli' in the previous season. We observed caterpillars and pupae of the butterfly exclusively in nests of M. schencki Em., i.e. 4 of 4 of them were infested. However, we did not find prematures of P. 'rebeli' with M. sabuleti Mein., M. rugulosa (Nyl.) and M. rubra (L.) which were also present in the turf. This makes the Pieniny population completely distinct from previously studied populations in SE Poland and similar to those known from Lithuania, France and Spain. It is probably related to the variation in chemical mimicry of P. 'rebeli' caterpillars. Our finding contributes to knowledge on the pattern of host-ant use of the butterfly in Europe and is also important for conservation on a local scale.
first rewind previous Strona / 1 next fast forward last
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.