DOI: 10.3897/contrib.entomol.76.e189193

Authors: Peter H. Roos

Abstract: Larval growth strategies and trajectories were analyzed in the genus Erebia Dalman 1816 in order to understand the interspecies variability in growth increments in connection with Dyar’s rule. For this, the number of larval moults and the size increments per moult were comparatively analyzed for the first time in a large number of phylogenetically closely related species, in this case within a single genus. Growth increments and trajectories were determined by measuring head capsule widths of each instar and the subsequent calculation of Dyar’s constant as well as by mathematical modeling, applying exponential, logarithmic and second order polynomial functions. Calculated parameters of the exponential and log functions were well suited for inter-species comparison. The frequency distributions of the growth increment parameters derived from 34 data sets are discontinuous, exhibiting four clear cut groups which can be attributed to the number of larval instars. Accordingly, variability of growth increments, expressed as Dyar’s constant, and of parameters derived from mathematical functions can be explained by the different number of moults. Developmental polymorphism has been shown for some species. In these cases, the different number of required instars, 4 or 5 of the same species, is associated to an altered growth increment, ultimately leading, however, to the same size in the last instar. The number of moults in an Erebia species is related to its life history, namely, to the number of hibernations in the larval stage. There is no association between instar numbers and phylogenetically defined species clusters.

HTML

XML

PDF

DOI: 10.3897/contrib.entomol.74.e125308

Authors: Jan Batelka, Michael Weingardt, Bernhard L. Bock, Rolf G. Beutel

Abstract: Five specimens of primary larvae of Ripiphoridae (Insecta: Coleoptera) are reported from one piece of Cretaceous Kachin amber. They represent two morphotypes: one conicocephalate and one belonging to the tribe Ripidiini (represented by four specimens). The conicocephalate morphotype is compared with similar larvae known from Kachin, Taimyr and Manitoba Cretaceous amber, and the larvae of Ripidiini are compared with their Cretaceous, Eocene and extant relatives. Phylogenetic analyses were performed to establish a working hypothesis about possible relationships of both lineages. The results, which conform with a recent molecular phylogeny, indicate that the larvae described here belong to Ripidiini or are closely related, respectively. To allow taxonomic and systematic work with conicocephalate larvae from Kachin amber, a collective group name †“Ripilarva” nov. is proposed here to accommodate these immature stages. Both species of †“Ripilarva” nov. from Kachin amber are described: †“R.” parabolica sp. nov. and †“R.” kachinensis sp. nov. Syninclusion of †“Ripilarva” kachinensis sp. nov. and four larvae of a species of Ripidiini indicate that females of both ripiphorids chose the same time and microhabitat for oviposition in the Kachin Cretaceous forest. The results are further verified by the use of UV-photography, as the different larval morphotypes occurred in the same resin flow. The presence of larvae of Ripidiini in clusters contrary to the solitary occurrence of †“Ripilarva” nov. in Cretaceous amber of Russia, Canada, USA, and Myanmar is interpreted as a possible result of different oviposition strategies, with different numbers of eggs deposited at one spot. Graphical abstract

HTML

XML

PDF

DOI: 10.3897/contrib.entomol.74.e119311

Authors: Holger Dathe

Abstract: na

HTML

XML

PDF

DOI: 10.3897/contrib.entomol.73.e109843

Authors: Ryoichi B. Kuranishi, Ryo Sato, Masashi Murakami

Abstract: We collected seven fixed pairs of Rhyacophila lezeyi during mating copulation and observed four different states of copulation. We investigated the underlying mechanism for the variations in the morphology of each copulating device, based on the copulation state. Notably, the male anal sclerites underwent considerable changes from the early stages of copulation. Initially, the female segment VIII approached the male anal sclerites, which were pushed downwards by the female VIII and IX segments, extending from IX. With the progression of mating stage, the distended end of the female’s segment VIII covered the anal sclerites, pushing them further down. The male parameres were initially folded in bellows-like shapes under the aedeagus before copulation initiation. However, as the copulation stage advanced, they extended to about 3.2 times of their original length. Distended ends of both parameres adhered to the position of the spiracles at the anterior margin of the lateral part of the female’s VII abdominal sternite. The attachment site was the external surface of the hair bulb of the male parameres. During the middle stage of copulation, movements involving the opening and closing of the male gonopods started. The gonoslylus made strong contact with the female’s abdominal segment VIII, resulting in the deformation of segment VIII due to the contact pressure.

HTML

XML

PDF

DOI: 10.3897/contrib.entomol.73.e110258

Authors: Wilfried Wichard

Abstract: The paper gives an overview of Trichoptera found as adults in mid-Cretaceous Burmese amber from about 100 million years ago. Fifty-eight extinct species are listed, three of which are still described here: Paduniella cretacea sp. nov., Palerasnitsynus vilarinoi sp. nov., Palleptocerus kuranishii sp. nov. The extinct subfamily Palerasnitsyninae stat. nov. of the family Xiphocentronidae is established and the extinct Bipectinata orientalis comb. nov. is transferred from the family Calamoceratidae to the family Odontoceridae. The extinct family Lepidochlamidae Wang et al., 2022, stat. nov. is transferred to the superfamily Leptoceroidea. The fifty-eight caddisflies of Burmese amber are distributed among twenty-one genera and fourteen families, of which fifteen genera and four families are also extinct. The large time distance between extinct and extant organisms makes the assignment to the extant genera and families difficult, because the higher taxa are defined according to the species living today and often do not or hardly correspond to the earlier species and their adaptations. Furthermore, in line with the hypothesis of a Gondwanan origin of Burmese amber, some embedded Trichopterans are discussed as relict descendants of Gondwanan Trichoptera, e.g. the family Palleptoceridae and the Xiphocentronid subfamily Palerasnitsyninae.

HTML

XML

PDF

DOI: 10.3897/contrib.entomol.73.e108068

Authors: Kseniia T. Abu Diiak, Mikhail Yu. Valuyskiy, Stanislav I. Melnitsky, Vladimir D. Ivanov

Abstract: Comparative study of sensory structures on maxillary and labial palps in 71 species from 14 families by scanning electron microscopy and light microscopy revealed significant diversity of sensory structures. Seven principal types of sensory structures were found: pointed trichoid, blunt chaetoid, campaniform, thin basiconic, thick basiconic, petaloid, and pseudoplacoid sensilla. Pointed trichoid and blunt chaetoid sensilla occur on every palp segment. First and, especially, second segments of maxillary palps have bunches of very large blunt chaetoid sensilla on medial surfaces. Campaniform sensilla were found only on basal segments. Pseudoplacoid sensilla are common on the terminal segments of both labial and maxillary palps except for Ptilocolepidae and Hydroptilidae. The petaloid sensilla forming the sensory fields are found in groups surrounded by the soft cuticle, generally in depressions, on the apical segments either on maxillary and labial palps in Hydrobiosidae and Rhyacophilidae, only on labial palps in other studied Integripalpia, or on apical labial palp segment and third and fourth maxillary palp segments in Annulipalpia. The pointed tips of both maxillary and labial palps in lower families have apical sensory complexes looking like small conical outgrowths without microtrichia, each with one large thick basiconic sensilla on its tip and several shorter thick basiconic sensilla on lateral surfaces. We consider these seven types of sensilla along with the apical sensory complex and the assemblage of the petaloid sensilla as a part of Trichoptera ground plan. This primitive diversity changes in evolution so the apical sensory complex, the fields of petaloid sensilla, the groups of very long blunt trichoid sensilla of basal segments, and the pseudoplacoid sensilla disappear in some advanced instances, more often on the maxillary palps. Interspecific variations of sensilla might be important for species discrimination, while the distribution of certain sensory structures is important for higher taxonomy.

HTML

XML

PDF

DOI: 10.3897/contrib.entomol.72.e87231

Authors: Oliver Nolte

Abstract:

HTML

XML

PDF

DOI: 10.3897/contrib.entomol.72.e87196

Authors: Zoltán Varga

Abstract: The oreal fauna is connected with orographically limited non-arboreal habitats. Its chorological centres can be recognised by the high species-diversity of numerous typical genera, and by the accumulated occurrence of endemic species and/or subspecies of disjunct species. The oreal fauna is partitioned to the alpine type, as the faunal type of humid high-mountains with strong connections to the tundral zonobiome, and the xeromontane type, as the faunal type of arid high-mountains with close connections to the eremic zonobiomes. As the results of revisions of several Noctuinae genera, species groups and/or sister species were recognised and their distributions were mapped. The restricted areas of allopatric sister species, often described by us as new for science, fulfil the criteria of the “areas of endemism”. Core areas of the Palaearctic xeromontane Noctuidae, outlined by the distribution of endemic species, have been proven by the occurrence of allopatric subspecies of polytypic species, and/or by the presence of allopatric sister species. In the revised genera of Noctuidae several types of allopatric speciation have been identified based on the analysis of the areas of endemism and of vicariance patterns. As a result of these analyses, it is proved that allopatric sister species, as elementary monophyletic supraspecific units, are suitable for phylogenetic biogeographical surveys. Although the major part of the xeromontane fauna appears to be range-restricted, a considerable fraction of the species could have expanded into the steppic zonobiome due to adaptive changes of their life cycles. High diversity of cold-adapted species originated from the Sino-Himalayan mountains by passing two main filtercorridors. One track of this bifurcation was directed across the “Rhododendron-corridor” to the Holarctic taiga zone while the other one, across the “Xeromontane filter-corridor” to the mountain systems of Central and Inner Asia. This bifurcation becomes apparent from the taxonomic division of the genera, composing both of these main faunal types. Supposedly, the faunal movements of the xeromontanean species in the West Palaearctic had been shaped by the Messinian salinity crisis and, additionally, significantly influenced by the Mid-Pleistocene climatic transition which deeply transformed the zonality of the vegetation by cooling and aridisation of vast areas.

HTML

XML

PDF