Bibliografie
2020
 © Oto Zimmermann
Autoři
Mgr. Jan Raška
Abstrakt
Adults and larvae of a true bug, Scantius aegyptius (Heteroptera: Pyrrhocoridae), closely resemble sympatric firebugs, Pyrrhocoris apterus, and probably form a mimetic relationship with the latter species. Scantius aegyptius adults, although producing a secretion atypical of true bugs, are to some extent chemically protected against predators. In this study, we analysed the composition and function of the larval secretion in S. aegyptius, and investigated the mimetic relationship between larvae of S. aegyptius and P. apterus. The main component of the larval secretion in S. aegyptius is 2-heptanol, a chemical not known to function in anti-predatory defence, followed by (E)-2-octenal, a common defensive chemical of true bugs. When larvae of both species were presented to jumping spiders (Evarcha arcuata), S. aegyptius was slightly less well protected than P. apterus, but the spiders behaved towards the two species in a similar way: they quickly learned to avoid the bugs, but usually attacked them again on the second day. The spiders also generalized their learned avoidance from one true bug species to the other (with only slight asymmetry favouring S. aegyptius), suggesting that the bugs’ mimetic relationship is most probably Müllerian, being advantageous to both species.

2018
 © Oto Zimmermann
Autoři
Mgr. Jan Raška
Abstrakt

Studies of aposematism are mostly focused on visual aspects of warning signalization and based on experiments with avian predators. This study presents results of experiments with an arthropod predator, a jumping spider Evarcha arcuata (Araneae: Salticidae) and olfactory (i.e., noncontact chemical) aposematic signals. Spiders were presented with chemically protected firebug Pyrrhocoris apterus (Heteroptera: Pyrrhocoridae). After acquiring the negative experience with the bugs, the spiders were offered a choice between the firebug olfactory signal and a scentless control. Spiders actively avoided the firebug signal, showing that they are able to recognize an unprofitable prey by means of olfactory chemoreception. The results show that olfactory signals alone may function as effective means of aposematic signalization to spiders.


2016
 © Ondřej Machač
Autoři
Mgr. Aleš Jelínek, Mgr. Jan Dolanský, Jan Erhart, Mgr. Jan Raška, RNDr. Milan Řezáč, Ph.D., Mgr. Ondřej Machač, Ph.D., RNDr. Petr Dolejš, Ph.D., RNDr. Vlastimil Růžička, CSc.
Abstrakt

Pavouci České republiky; Zavlečenci; Méně známé druhy pavouků Nuctenea silvicultrix; Nová pravidelná rubrika "Významné nálezy pavouků v ČR"; Významné nálezy pavouků z ČR I./Remarkable records of spiders from Czech Republic I.; Nález pavučenky Diplocephalus dentatus Tullgren, 1955; Poznámka k výskytu zápředníka Clubiona corticalis (Walckenaer, 1802); Klíšťata - neobvyklá kořist pavouků; Kořist larev hrabalek; Přírodní rozmanitost Vysočiny - výzva ke spolupráci; Zoodny České Budějovice 2016; Arachnologická exkurze 2016: Údolí Jihlavy a Oslavy; Česká bibliografie 2016; Britská bibliografie - The Newsletter 135; Pokyny pro autory


2012
Autoři
Mgr. Jan Raška
Abstrakt
Originalni ID: 1030

Statistiky

Nalezeno

3
Nálezy
3
Druhy
3
Rody
3
Čtverce

Určeno

3
Nálezy
3
Druhy
3
Rody
3
Čtverce
Fotografie
1
Počet
1
Druhy