Development and localization of microsatellite markers for the sibling species Chironomus riparius and Chironomus piger (Diptera: Chironomidae)

Five variable microsatellite loci are reported for the nonbiting midge species Chironomus riparius and Chironomus piger. All loci show considerable intraspecific variation and species‐specific alleles, which allow to discriminate among the two closely related species and their interspecific hybrids, and to estimate genetic diversity within and between populations. Additionally, the loci were localized on C. riparius polytene chromosomes to verify their single copy status and investigate possible chromosomal linkage. The described markers are used in different studies with regard to population and ecological genetics and evolutionary ecotoxicology of Chironomus.     

Central Mechanisms of Frog Galling

The central mechanisms of release calling and mating callingin the Northern leopard frog (Rana pipiens pipiens) and thegreen tree frog (Hyla cinerea) are discussed. The region ofthe ventral magnoceHifl-ar preoptic nucleus is essential formiating calling. This area probably contains androgen receptorsthat project to, and activate, more posterior calling mechanisms.The region of the main sensory nucleus V is involved, in a mannernot yet clearly understood, in calling. Perhaps this area servesas a sensory correlation center that receives and analyzes avariety of sensory inputs, determines what type of call constitutesan appropriate response, and then excites the calling circuitsat more posterior levels. The region of the hypoglossal andvagus motor nuclei is essential for release calling. This areaprobably serves as a motor coordination center that organizesthe motor patterns of calling.     

Trap‐jaws revisited: the mandible mechanism of the ant Acanthognathus

Abstract.Ants of the genus Acanthognathus stalk small insects and catch their prey by a strike with their long, thin mandibles. The mandibles close in less than 2.5 ms and this movement is controlled by a specialized closer muscle. In Acanthognathus , unlike other insects, the mandible closer muscle is subdivided into two distinct parts: as in a catapult, a large slow closer muscle contracts in advance and provides the power for the strike while the mandibles are locked open. When the prey touches specialized trigger hairs, a small fast closer muscle rapidly unlocks the mandibles and thus releases the strike. The fast movement is steadied by large specialized surfaces in the mandible joint and the sensory‐motor reflex is controlled by neurones with particularly large, and thus fast‐conducting, axons.     

A conifer seedling with two herbicolous fungi from the Baltic amber forest

A Baltic amber inclusion of a fossil spruce seedling of which the lower part of the hypocotyl and the primary root are not preserved is provisionally described as Picea baltica ad int. The remnant of the hypocotyl and the basal parts of the cotyledons are infested by a conidial fungus. Its conidiophores correspond to those of the genus Gonatobotryum Corda. However, the fungus is not assignable to any extant species and is therefore described as a new species, Gonatobotryum piceae . A further infestation, most probably by a stroma-forming anamorph, is visible on the cotyledons of the seedling. Its mode of infestation is similar to that of Sirococcus strobilinus Preuss which occurs in extant spruce seedlings.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 155 , 449–456.     

A Burgess Sale

Conway Morris, S., Whittington, H. B., Briggs, D. E. G., Hughes, C. P. & Bruton, D. L. 1982: Atlas of the Burgess Shale. .