Structural variation in the genitalia of the Panorpa alpina-complex (Mecoptera)

Abstract. The genitalia of both males and females of the P.alpina-complex are highly variable, both within and between sites, and sometimes bilaterally asymmetric. On the basis of this variation five species are placed in synonymy with Panorpa alpina Rambur: antiporum Nagler; plitvicensis Lauterbach; pseudoalpina Nagler; pura Klapalek; susteri Nagler. The sub-genus Aulops is placed once again in synonymy with Panorpa.     

Mitochondrial gene fragments suggest paraphyly of the genus Panorpa (Mecoptera, Panorpidae)

Life history studies of scorpionfly species have been used to test predictions of evolutionary theory, but comparative analysis has been hampered by a lacking phylogeny of scorpionflies. We present a molecular phylogeny of selected panorpid scorpionflies inferred from mitochondrial 12S, 16S rRNA, and COI gene fragments, using parsimony and maximum-likelihood methods. Maximum-likelihood reconstructions depend on an explicit evolutionary substitution model; therefore, we estimated fit of substitution models to our data and used an optimal evolutionary substitution model in subsequent reconstructions. Both reconstruction methods converge on compatible trees with considerable statistical support for a majority of nodes. We performed parametric tests of most important phylogenetic conclusions employing the fitted GTR + %I + Gamma substitution model. Parametric bootstrapping allowed rejection of alternative explanations of the data set, where classical tests, like the KHY test, failed. Parametric bootstrapping confirmed that the association of Neopanorpa sp. with Asian Panorpa species is currently the superior explanation of the data set. Therefore, it is concluded that the genus Panorpa is most likely paraphyletic to the representative of the genus Neopanorpa. We conclude that the sequenced mitochondrial gene fragments appear to be well suited for future more comprehensive phylogenetic investigations of panorpid scorpionflies.     

An intranuclear paracrystalloid body in the gametocytes of Panorpa communis (Mecoptera)

During the meiotic prophase the nuclei of the spermatocytes and oocytes of Panorpa communis contain a paracrystalloid body (PB). This is built up of about 100 filaments of 80 Å thickness all running parallel to one another. The filaments are connected by a network of many thin fibers. At pachytene and diplotene the PB is connected with the nucleolus. In spermatocytes at late diplotene the PB is enveloped by RNP-material, which is produced by certain chromosomes at the diffuse diplotene stage. Thereafter the PB is gradually removed. During this process the RNP-material coils up to form three or four spherical RNP-bodies. It is suggested that the PB has a function in assembling and connecting the RNP-material to form long ribbons which build up the RNP-bodies.     

The larval abdomen of the enigmatic Nannochoristidae (Mecoptera,Insecta)

External and internal structures of the larval abdomen of Nannochorista are described in detail, with emphasis on the posterior segments. The results are compared with conditions found in other groups of Antliophora, especially the mecopteran subgroups Boreidae and Pistillifera. Like the entire postcephalic body, the larval abdomen of Nannochorista is extremely slender and nearly cylindrical. The anterior segments are largely unmodified. The surface is smooth and lacks any protuberances or prolegs. The term “cloaca” for the posterior membranous pouch of Nannochorista sp. is morphologically unjustified. A list of muscles of segments IX and X is presented. The abdominal musculature was partly homologized following Snodgrass. The muscles of segment X are highly modified. They move the membranous pouch, the anal papillae, and the terminal lobes. The presence of these structures is likely an adaptation to the specific aquatic life style of nannochoristid larvae. The anal papillae are possibly homologous to the 4-lobed terminal attachment apparatus of larvae of Caurinus (Boreidae) and Pistillifera (Panorpidae, Bittacidae, Choristidae) but this is uncertain. The specific condition in both groups, i.e. two retractile papillae with tracheae and Malpighian tubules in Nannochoristidae, and a 4-lobed exposed attachment device in Pistillifera + Boreidae (groundplan) are very likely autapomorphic for both groups, respectively. A slender abdomen with smooth surface is very likely plesiomorphic within Antliophora and Mecopterida. This condition is found in Trichoptera (partim), Nannochoristidae, Siphonaptera, and many basal groups of Diptera. An eruciform or scarabaeiform body shape with a soft, largely unsclerotised cuticle is probably a synapomorphy of Boreidae and Pistillifera. The presence of ventral protuberances resembling prolegs on the anterior segments is an autapomorphy of the latter group. The homology of paired or unpaired terminal appendages of segment X is uncertain. However, the specific condition of paired and 3-segmented appendages with hooks in Nannochoristidae is almost certainly autapomorphic for this family. The protracted opening of the hind gut on the membranous pouch is another potential autapomorphy of Nannochoristidae. Aquatic habits of larvae, also very likely an apomorphic condition, have likely evolved several times independently in Antliophora.     

Alternative Female Choice Tactics in the Scorpionfly Hylobittacus apicalis(Mecoptera) and Their Implications

Females of the scorpionfly Hylobittacus apicalis choose mateson the basis of material benefits (nuptial arthropod prey size)and probably on the basis of genetic benefits males deliverat mating. Females feed on the male's prey throughout copulation.They prefer males with large prey as mates and often refusemales who present small prey. That females may value male geneticquality is suggested by differences in ability of males to obtainlarge prey, which if inherited would influence offspring fitness,and by females often terminating mating with males with smallprey before they transfer any sperm or a complete ejaculate.Females hunt only when males with prey are not available becausehunting exposes individuals to predators. Female Hylobittacusapicalis exhibit alternative mate choice tactics, which arecondition-dependent in expression and probably comprise a conditionalstrategy. Body size, recent feeding history, and male availabilitydetermine how discriminating an individual female actually is,and these conditions may determine the value of material andgenetic benefits in mate choice decisions. The results suggestthat female choice controls male behavior. When females becomechoosy, males are forced to obtain rare large prey despite theincreased risks to males associated with this behavior. The implications of the findings on H. apicalis are discussedin relation to condition dependent female choice patterns inother species and the evolutionary maintenance of female choice.     

Female mating frequency in a wild population of scorpionflies (Panorpa germanica, Panorpidae, Mecoptera)

In this study, we investigated mating frequencies of female scorpionflies Panorpa germanica in the field using two different experimental approaches. First, the mating status of wild‐caught females was estimated on the basis of sperm numbers present inside their sperm storage organs. Secondly, the number of mating partners wild‐caught females must have had was inferred from mother‐offspring analyses of a polymorphic microsatellite locus. Our results suggest a very low mating frequency of wild female P. germanica. Consequently, the risk of sperm competition is rather low in this species. The relevance of female mate choice in relation to the low mating frequency is discussed.     

The Influence of Pedipalp Autotomy on the Courtship and Mating Behavior of Pardosa milvina (Araneae: Lycosidae)

Male Pardosa milvina wolf spiders use their pedipalps both for copulation and courtship. Pedipalp loss is significantly more common among adult males compared to females. We measured the courtship and mating effects associated with the loss of one or both pedipalps among adult male P. milvina. Pedipalp loss significantly reduced courtship intensity, but had no influence on mounting success. Intact males were less likely to be cannibalized and suffered fewer predatory attacks by females than autotomized males. Loss of the left pedipalp resulted in significantly less intense courtship, higher female aggression levels, and delayed onset of courtship whereas loss of the right pedipalp minimally affected male and female behavior relative to intact males. Pedipalp displays may function in reducing female aggression rather than increasing female receptivity.     

A well-preserved aneuretopsychid from the Jehol Biota of China (Insecta, Mecoptera, Aneuretopsychidae)

The Aneuretopsychidae is an unspeciose and enigmatic family of long-proboscid insects that presently consist of one known genus and three species from the Late Jurassic to Early Cretaceous of north-central Asia. In this paper, a new genus and species of fossil aneuretopsychid is described and illustrated, Jeholopsyche liaoningensisgen. et sp. n. Fossils representing this new taxon were collected from mid Early Cretaceous strata of the well known Jehol Biota in Liaoning Province, China. This finding documents the first formal record of fossil Aneuretopsychidae in China. In addition, this well-preserved and new material reveals previously unknown and detailed morphological structure of the mouthparts, antennae, head, thorax, legs and abdomen of this distinctive insect lineage.     

Larval morphology of Panorpodes kuandianensis (Insecta,Mecoptera, Panorpodidae) and its evolutionary implications

Larval characters play a significant role in evolutionary and systematic studies of holometabolous insects. However, Panorpodidae, a derived family of Mecoptera, are largely unknown in their immature stages to date. Here, the first instar larva of the short-faced scorpionfly Panorpodes kuandianensis Zhong, Zhang & Hua, 2011 is described and illustrated using light and scanning electron microscopy. The larva of Panorpodes is remarkable for the absence of compound eyes on the head and the presence of seven small unpaired proleg-like processes along the midventral line on abdominal segments II–VIII. The homology of these unpaired appendage-like processes, their ecological adaptation, and the evolutionary implications of some larval characters of Panorpodidae are discussed.     

Courtship and Mating in the Giant Hairy Desert Scorpion, Hadrurus arizonensis (Scorpionida, Iuridae)

Hadrurus arizonensis is a large, long-lived species of North American desert scorpion with lengthy, stereotyped courtship behaviors that lead to sperm transfer via an external spermatophore. Courtship and mating behaviors in H. arizonensis and other members of the Iuridae family have not been described. H. arizonensis has reproductive behavior similar to that of other scorpions, including the promenade a deux, but with some unique components described here for the first time. Courtship and mating behaviors of H. arizonensis are presented in a flowchart to emphasize its stereotypical nature and suitability for experimental manipulation in field and laboratory studies.     

Ultrastructure and function of the seminal vesicle of Bittacidae (Insecta: Mecoptera)

The fine structure of the seminal vesicle and reproductive accessory glands was investigated in Bittacidae of Mecoptera using light and transmission electron microscopy. The male reproductive system of Bittacidae mainly consists of a pair of testes, a pair of vasa deferentia, and an ejaculatory sac. The vas deferens is greatly expanded for its middle and medio-posterior parts to form a well-developed seminal vesicle. The seminal vesicle is composed of layers of developed muscles and a mono-layered epithelium surrounding the small central lumen. The epithelium is rich in rough endoplasmic reticulum and mitochondria, and secretes vesicles and granules into the central lumen by merocrine mechanisms. A pair of elongate mesodermal accessory glands opens into the lateral side of the seminal vesicles. The accessory glands are similar to the seminal vesicle in structure, also consisting of layers of muscle fibres and a mono-layered elongated epithelium, the cells of which contain numerous cisterns of rough endoplasmic reticulum and mitochondria, and a few Golgi complexes. The epithelial cells of accessory glands extrude secretions via apocrine and merocrine processes. The seminal vesicles mainly serve the function of secretion rather than temporarily storing spermatozoa. The sperm instead are temporarily stored in the epididymis, the greatly coiled distal portion of the vas deferens.     

Histology and ultrastructure of the salivary glands and salivary pumps in the scorpionfly Panorpa obtusa (Mecoptera: Panorpidae)

Liu, S. and Hua, B. 2009. Histology and ultrastructure of the salivary glands and salivary pumps in the scorpionfly Panorpa obtusa (Mecoptera: Panorpidae). —Acta Zoologica (Stockholm) 91 : 457–465. The morphology, histology and ultrastructure of the salivary glands and salivary pumps in the scorpionfly Panorpa obtusa Cheng 1949 were investigated using light microscopy and scanning and transmission electron microscopy. The salivary glands display a distinct sexual dimorphism. The female has only two small sac‐like glands located in the prothorax, while the male possesses six long tubular glands extending into the sixth abdominal segment. The male salivary glands can be divided into five distinct regions. The apical long, thin secretory region possesses numerous secretory cells containing large secretory vesicles; the salivary reservoir expands in diameter, accumulating and temporarily storing the saliva in addition to secreting saliva; the constricted region contains prismatic cells with complex infolded plasma membrane; the sac has an internal brush border to absorb water and ions; the common salivary duct contains longitudinal muscles in the male, but not in the female. The salivary pump possesses independent strong dorsal muscles and abundant internal palm spines near its orifice. The anatomy and ultrastructure of the salivary glands and the salivary pump of scorpionflies as well as their possible functions are briefly discussed.     

New scorpionflies (Insecta: Mecoptera: Permochoristidae) from the Ufimian of Cisuralia

Two new species of Protopanorpa Carpenter (Mecoptera: Permochoristidae), P. longicubitalis sp. nov. and P. similis sp. nov. from the Ufimian Solikamsk Horizon of the Perm Region (Tyulkino locality) are described. Scorpionflies of Tyulkino are compared with scorpionflies of the Kungurian Chekarda locality (Perm Region) and the Early Kazanian Soyana locality (Arkhangelsk Region).