Search results for "Insecta"
showing 10 items of 265 documents
Ultrastructure and formation of the physogastric termite queen cuticle
1982
0040-8166 (Print) Journal Article; The physogastric termite queen is the most striking example in insects of growth in size without cuticular moulting. This phenomenon has been studied with electron microscopy and histochemical tests in two species of higher termites, Cubitermes fungifaber and Macrotermes bellicosus. The abdominal hypertrophy (physogastry) is allowed by growth of the arthrodial membranes of the swarming imago. The growth is slow (over several years) but important: the cuticular dry weight is multiplied by 20 in C. fungifaber, by 100-150 in M. bellicosus. The termite queen cuticle arises from the transformation of the cuticle of the swarming imago or imaginal cuticle (unfold…
New Afrotropical species of the genus Coridiellus J.A. Lis, 1990 with a key to its species (Hemiptera: Heteroptera: Dinidoridae)
2020
Coridiellus pseudocyclopeltus, a new species of the dinidorid subfamily Dinidorinae, is described from Zaire and is compared with Coridiellus cyclopeltus (Distant, 1890). It is the seventh species of this genus known from Afrotropical Region. A key to all the species of the genus Coridiellus is also provided. Male parameres are used for identification and their photographs are given for the first time for all species of the genus.
Paternal signature in kin recognition cues of a social insect: concealed in juveniles, revealed in adults
2014
Kin recognition is a key mechanism to direct social behaviours towards related individuals or avoid inbreeding depression. In insects, recognition is generally mediated by cuticular hydrocarbon (CHC) compounds, which are partly inherited from parents. However, in social insects, potential nepotistic conflicts between group members from different patrilines are predicted to select against the expression of patriline-specific signatures in CHC profiles. Whereas this key prediction in the evolution of insect signalling received empirical support in eusocial insects, it remains unclear whether it can be generalized beyond eusociality to less-derived forms of social life. Here, we addressed this…
Some new species of Phaneroptera, Eulioptera and Scolocerca (Orthoptera Tettigoniidae: Phaneropterinae) from West Tropical Africa
2021
The author describes Phaneroptera abdita n. sp., characterized by only two apical spurs; two new species of Eulioptera, E. iolandae n. sp. with unarmed fore coxae, E. atypica n. sp., with atypical opaque tegmina; and Scolocerca thomasi n. sp., all from West Tropical Africa. In addition, he discusses on the probable only African distribution of Phaneroptera sparsa Stål, 1857, and transfers Dithela longicaudata Massa, 2017 to the genus Eulioptera Ragge, 1956.
Redescription and new records of the monotypic genus Trynocoris Herring, 1976 (Heteroptera: Miridae: Cylapinae: Fulviini).
2019
Trynocoris lawrencei Herring, the only representative of the genus Trynocoris and only known from Barro Colorado Island, Canal Zone, Panama, is recorded for the first time from Mexico, Nicaragua, Panama: Chinqui and Ecuador. Redescription of the genus and species are given along with color photographs of the adults, scanning electron micrographs of selected structures of T. lawrencei. Illustrations of the tarsi and male genitalia are presented for the first time.
Sibling cooperation in earwig families provides insights into the early evolution of social life.
2014
The evolutionary transition from solitary to social life is driven by direct and indirect fitness benefits of social interactions. Understanding the conditions promoting the early evolution of social life therefore requires identification of these benefits in nonderived social systems, such as animal families where offspring are mobile and able to disperse and will survive independently. Family life is well known to provide benefits to offspring through parental care, but research on sibling interactions generally focused on fitness costs to offspring due to competitive behaviors. Here we show experimentally that sibling interactions also reflect cooperative behaviors in the form of food sh…
Towards reliable identification of male Dicerura: descriptions of three new and seven poorly known species in the Palearctic region (Diptera: Cecidom…
2018
The taxonomy of Dicerura Kieffer, 1898, a genus of Porricondylinae now comprising 32 species in the Holarctic region, is revised. Three new species are described based on morphological characters of male adults: D. jakovlevi Jaschhof & Spungis sp. nov. (from Finland), D. penttineni Jaschhof & Spungis sp. nov. (Finland), and D. yezoensis Jaschhof & Spungis sp. nov. (Japan). Dicerura padi Mamaev, 1975 syn. nov. is revealed to be a junior synonym of D. furculata Mamaev, 1968. Seven species, whose original descriptions are from a present-day perspective inadequate for the purpose of identification, are redescribed: D. barbata Mamaev, 1966; D. formosa Mamaev, 1998; D. foliicola Mamae…
Condition-Dependent Trade-Off Between Weapon Size and Immunity in Males of the European Earwig
2017
Abstract Investigating the expression of trade-offs between key life-history functions is central to our understanding of how these functions evolved and are maintained. However, detecting trade-offs can be challenging due to variation in resource availability, which masks trade-offs at the population level. Here, we investigated in the European earwig Forficula auricularia whether (1) weapon size trades off with three key immune parameters – hemocyte concentration, phenoloxidase and prophenoloxidase activity - and whether (2) expression and strength of these trade-offs depend on male body condition (body size) and/or change after an immune challenge. Our results partially confirmed conditi…
SIMULATING RANGE EXPANSION: MALE SPECIES RECOGNITION AND LOSS OF PREMATING ISOLATION IN DAMSELFLIES
2009
Prolonged periods of allopatry might result in loss of the ability to discriminate against other formerly sympatric species, and can lead to heterospecific matings and hybridization upon secondary contact. Loss of premating isolation during prolonged allopatry can operate in the opposite direction of reinforcement, but has until now been little explored. We investigated how premating isolation between two closely related damselfly species, Calopteryx splendens and C. virgo, might be affected by the expected future northward range expansion of C. splendens into the allopatric zone of C. virgo in northern Scandinavia. We simulated the expected secondary contact by presenting C. splendens fema…
INTERSPECIFIC AGGRESSION CAUSES NEGATIVE SELECTION ON SEXUAL CHARACTERS
2005
Interspecific aggression originating from mistaken species recognition may cause selection on secondary sexual characters, but this hypothesis has remained untested. Here we report a field experiment designed to test directly whether interspecific aggression causes selection on secondary sexual characters, wing spots, in wild damselfly populations. Males of Calopteryx virgo are more aggressive toward males of C. splendens with large than with small wing spots. This differential interspecific aggression may cause negative selection on wing spot size. Indeed, our results show that directional survival selection on wing spot size of C. splendens males was changed by experimental removal of C. …