Morphology of the pretarsus of the sawflies and horntails (Hymenoptera: 'Symphyta')

The pretarsal structures have been studied in representatives of 13 families of 'Symphyta' by means of light microscopy. The pretarsal sclerites (manubrium, planta, and unguitractor) vary in shape among different families. The shape of the manubrium is triangular in representatives of Xyelidae and Orussidae and bifurcated in those of Tenthredinoidea. For representatives of Siricomorpha, an elongated shape of the manubrium is typical with such variations, as distally expanded, proximally expanded, clavate, spear-shaped. Plantae of different Symphyta vary in shape and level of sclerotization. In representatives of Siricidae, the female manubrium and arolium are significantly reduced, and arcus and dorsal plates are completely absent. Siricid males possess all pretarsal sclerites and a well-developed arolium. Auxiliary sclerites are absent in representatives of Orussidae. Trichoid sensilla are absent on the plantae in representatives of Cephidae and Orussidae. Other studied Symphyta possess two trichoid sensilla on the planta. Representatives of all investigated families bear two campaniform sensilla on the manubrium, with the exception of Siricidae having three sensilla. Kinematics of the pretarsus with bifurcated manubrium are modeled and discussed.     

Phylogenetics and classification of Chalcidoidea and Mymarommatoidea — a review of current concepts (Hymenoptera, Apocrita)

Classification and morphological and molecular evidence supporting relationships of Mymarommatidae (Mymarommatoidea) and the 20 families of Chalcidoidea are reviewed. Five autapomorphies support monophyly of Mymarommatoidea, at least two autapomorphies support monophyly of Chalcidoidea, and three synapomorphies support a sister-group relationship between Mymarommatoidea and Chalcidoidea. Mymaridae are indicated as the likely sister group of all other Chalcidoidea by: two features of the ovipositor, the unique structure of a muscle between the mesofurca and axillary lever, and sequence data from the 28s rDNA gene. Structure of the upper valvulae of the ovipositor could indicate Rotoitidae as the second-most basal clade of Chalcidoidea. Chalcididae, Elasmidae, Encyrtidae, Eulophidae, Eurytomidae, Leucospidae, Mymaridae, Ormyridae, Rotoitidae, Signiphoridae, Torymidae and Trichogrammatidae are each indicated as monophyletic by at least one putative synapomorphy, but could render other families paraphyletic. Aphelinidae, Eupelmidae, Pteromalidae, and Tetracampidae are not demonstrably monophyletic. Agaonidae is monophyletic only if restricted to Agaoninae, and Eucharitidae is monophyletic only if restricted to Eucharitinae + Oraseminae. Eupelmidae may be paraphyletic with respect to Tanaostigmatidae and Encyrtidae, and Tanaostigmatidae including Cynipencyrtus may be paraphyletic relative to Encyrtidae. Perilampidae (Perilampinae + Chrysolampinae) are either polyphyletic or paraphyletic with respect to Eucharitidae + Akapalinae + Philomidinae. No cladistic hypotheses of familial relationships based on character evidence have considered the superfamily in its entirety.     

Distal leg structures of the Aculeata (Hymenoptera): A comparative evolutionary study of Sceliphron (Sphecidae) and Formica (Formicidae)

The distal parts of the legs of Sceliphron caementarium (Sphecidae) and Formica rufa (Formicidae) are documented and discussed with respect to phylogenetic and functional aspects. The prolegs of Hymenoptera offer an array of evolutionary novelties, mainly linked with two functional syndromes, walking efficiently on different substrates and cleaning the body surface. The protibial-probasitarsomeral cleaning device is almost always well-developed. A complex evolutionary innovation is a triple set of tarsal and pretarsal attachment devices, including tarsal plantulae, probasitarsomeral spatulate setae, and an arolium with an internal spring-like arcus, a dorsal manubrium, and a ventral planta. The probasitarsal adhesive sole and a complex arolium are almost always preserved, whereas the plantulae are often missing. Sceliphron has retained most hymenopteran ground plan features of the legs, and also Formica, even though the adhesive apparatus of Formicidae shows some modifications, likely linked to ground-oriented habits of most ants. Plantulae are always absent in extant ants, and the arolium is often reduced in size, and sometimes vestigial. The arolium contains resilin in both examined species. Additionally, resilin enriched regions are also present in the antenna cleaners of both species, although they differ in which of the involved structures is more flexible, the calcar in Sceliphron and the basitarsal comb in Formica. Functionally, the hymenopteran distal leg combines (a) interlocking mechanisms (claws, spine-like setae) and (b) adhesion mechanisms (plantulae, arolium). On rough substrate, claws and spine-like setae interlock with asperities and secure a firm grip, whereas the unfolding arolium generates adhesive contact on smooth surfaces. Differences of the folded arolium of Sceliphron and Formica probably correlate with differences in the mechanism of folding/unfolding.     

A molecular phylogeny of the Chalcidoidea (Hymenoptera)

Chalcidoidea (Hymenoptera) are extremely diverse with more than 23,000 species described and over 500,000 species estimated to exist. This is the first comprehensive phylogenetic analysis of the superfamily based on a molecular analysis of 18S and 28S ribosomal gene regions for 19 families, 72 subfamilies, 343 genera and 649 species. The 56 outgroups are comprised of Ceraphronoidea and most proctotrupomorph families, including Mymarommatidae. Data alignment and the impact of ambiguous regions are explored using a secondary structure analysis and automated (MAFFT) alignments of the core and pairing regions and regions of ambiguous alignment. Both likelihood and parsimony approaches are used to analyze the data. Overall there is no impact of alignment method, and few but substantial differences between likelihood and parsimony approaches. Monophyly of Chalcidoidea and a sister group relationship between Mymaridae and the remaining Chalcidoidea is strongly supported in all analyses. Either Mymarommatoidea or Diaprioidea are the sister group of Chalcidoidea depending on the analysis. Likelihood analyses place Rotoitidae as the sister group of the remaining Chalcidoidea after Mymaridae, whereas parsimony nests them within Chalcidoidea. Some traditional family groups are supported as monophyletic (Agaonidae, Eucharitidae, Encyrtidae, Eulophidae, Leucospidae, Mymaridae, Ormyridae, Signiphoridae, Tanaostigmatidae and Trichogrammatidae). Several other families are paraphyletic (Perilampidae) or polyphyletic (Aphelinidae, Chalcididae, Eupelmidae, Eurytomidae, Pteromalidae, Tetracampidae and Torymidae). Evolutionary scenarios discussed for Chalcidoidea include the evolution of phytophagy, egg parasitism, sternorrhynchan parasitism, hypermetamorphic development and heteronomy.     

A phylogenetic analysis of the megadiverse Chalcidoidea (Hymenoptera)

Chalcidoidea (Hymenoptera) is extremely diverse with an estimated 500 000 species. We present the first phylogenetic analysis of the superfamily based on both morphological and molecular data. A web‐based, systematics workbench mx was used to score 945 character states illustrated by 648 figures for 233 morphological characters for a total of 66 645 observations for 300 taxa. The matrix covers 22 chalcidoid families recognized herein and includes 268 genera within 78 of 83 subfamilies. Morphological data were analysed alone and in combination with molecular data from ribosomal 18S (2105 bp) and 28S D2–D5 expansion regions (1812 bp). Analyses were analysed alone and in combined datasets using implied‐weights parsimony and likelihood. Proposed changes in higher classification resulting from the analyses include: (i) recognition of Eriaporidae, revised status; (ii) recognition of Cynipencyrtidae, revised status; (iii) recognition of Azotidae, revised status; (iv) inclusion of Sycophaginae in Agaonidae, revised status; (v) reclassification of Aphelinidae to include Aphelininae, Calesinae, Coccophaginae, Eretmocerinae and Eriaphytinae; (vi) inclusion of Cratominae and Panstenoninae within Pteromalinae (Pteromalidae), new synonymy; (vii) inclusion of Epichrysomallinae in Pteromalidae, revised status. At a higher level, Chalcidoidea was monophyletic, with Mymaridae the sister group of Rotoitidae plus the remaining Chalcidoidea. A eulophid lineage was recovered that included Aphelinidae, Azotidae, Eulophidae, Signiphoridae, Tetracampidae and Trichogrammatidae. Eucharitidae and Perilampidae were monophyletic if Eutrichosomatinae (Pteromalidae) was included, and Eupelmidae was monophyletic if Oodera (Pteromalidae: Cleonyminae) was included. Likelihood recovered a clade of Eupelmidae + (Tanaostigmatidae + (Cynipencyrtus + Encyrtidae). Support for other lineages and their impact on the classification of Chalcidoidea is discussed. Several life‐history traits are mapped onto the new phylogeny.     

Phylogenetic implications of the mesofurca in Chalcidoidea (Hymenoptera), with emphasis on Aphelinidae

The skeletomusculature of the mesofurcal–mesopostnotal complex is surveyed within the Chalcidoidea. Four internal character systems are assessed for their phylogenetic significance: the mesofurcal bridge, the structure and position of the furcal–laterophragmal muscle, the structure of the lateral arms of the mesofurca, and the supporting structures for the interfurcal muscles. Among Hymenoptera, Chalcidoidea are unique in having the furcal–laterophragmal muscle attached along the entire length of the laterophragmal apodeme. Also the furcal–laterophragmal muscle originates medial to the junction of the mesofurcal bridge and lateral mesofurcal arm in most Chalcidoidea. Mymarommatidae do not share either of these apomorphic states with Chalcidoidea. Within Chalcidoidea, apomorphic character states were found in each of Aphelinidae, Encyrtidae, Eulophidae, Mymaridae, Rotoitidae, Signiphoridae, Tanaostigmatidae and Trichogrammatidae. For taxa classified as Aphelinidae, the plesiomorphic complement of structures and muscle attachments is retained in Eriaphytinae and Eriaporinae. The mesofurcal bridge is considered to have been lost at least twice in each of Aphelininae and Coccophaginae. Similar interfurcal processes, resulting from loss of the mesofurcal bridge, support the monophyly of Aphelininae (Aphelinini, Aphytini and Eutrichosomellini). Azotinae are placed as the sister group of Aphelininae because of a similar lateral origin of the laterophragmal muscle and the shape of the mesofurcal arms. Other than loss of the mesofurcal bridge, no character states were shared by Azotinae and Coccophaginae. Coccophaginae (Coccophagini and Pteroptricini) are regarded as monophyletic based on the loss of the mesofurcal bridge, the peculiar shape of the mesofurca, and a unique modification of the laterophragmal muscle. Euxanthellus is removed from synonomy with Coccophagus and may be best treated as a separate tribe of Coccophaginae based on the shape of the lateral mesofurcal arms and the presence of a mesofurcal bridge. The shape of the mesofurca suggests a monophyletic grouping of Cales, Eretmocerus and Trichogrammatidae that could render Aphelinidae paraphyletic.     

Pretarsal structures in Reduviidae (Heteroptera, Ins ecta)

A survey of pretarsal structures in Reduviidae of 22 higher‐level taxa and several outgroup representatives is conducted using scanning electron microscopy (SEM) and light microscopy. Based on histology and SEM, pretarsal structures are described in detail for Rhodnius prolixus. Structures of the distal tarsomer, which appear to be functionally correlated with the pretarsus, are documented for the first time in Heteroptera. These comprise lateral oval sclerites, two campaniform sensilla and two marginal setae, observed in Reduviidae and other heteropteran taxa. The presence of a peg‐like dorsomedian sensillum medially between the claws in Reduviidae and Nabidae is demonstrated. As a result of its structure and position, homology of this sensillum with the ‘dorsal arolium’ in other heteropteran groups is proposed. Within Reduviidae, the transformation of the peg‐like dorsomedian sensillum to a campaniform sensillum, as seen in most representatives of the harpactoroid complex, is hypothesized. The first record of parempodia other than setiform within Reduviidae is noted in nymphs of Harpactorinae, which may possess lamellate parempodia. Several characters that are possibly useful for clarifying relationships among the harpactoroid groups are described and discussed. The pretarsal structures, including the unguitractor plate and the tarsal marginal setae among reduviid groups are discussed in a phylogenetic context.     

Arcus as a tensegrity structure in the arolium of wasps (Hymenoptera: Vespidae)

The unfolding of the hymenopteran attachment pad (arolium) may be achieved in two ways, hydraulic and mechanical. The first was confirmed in experiments with pressure applied to more proximal leg parts and on immersion in hypotonic solutions. Presumably, this way of unfolding does not play an important role for a living hornet. Mechanical unfolding was studied experimentally with the aid of a micromanipulator pulling the tendon of the musculus retractor unguis. Ablation experiments on different parts of the arolium indicated that the arcus is the most crucial element for mechanical unfolding. The shape of the arcus in closed and open conditions was measured using a 3D measurement microscope and reconstructed by means of 3D computer graphics. The arcus coils up upon being freed from the arolium tissues, and coils up even more after immersion into a 10% aqueous solution of NaOH. Geometrical models of the arcus are proposed, from which the rotational moment of elasticity is derived. Conformations and deformations of the arcus are quantified in order to explain its role in the folding and unfolding processes of the arolium. The diversity of approaches supports the idea that the arcus is a prestressed (tensegrity) structure providing immediate, soft, and graded transmission of forces during folding and unfolding action of the arolium.     

Phylogeny of pteromalid parasitic wasps (Hymenoptera: Pteromalidae): initial evidence from four protein-coding nuclear genes

Chalcidoidea (approximately 22,000 described species) is the most ecologically diverse superfamily of parasitic Hymenoptera and plays a major role in the biological control of insect pests. However, phylogenetic relationships both within and between chalcidoid families have been poorly understood, particularly for the large family Pteromalidae and relatives. Forty-two taxa, broadly representing Chalcidoidea but concentrated in the 'pteromalid lineage,' were sequenced for 4620 bp of protein-coding sequence from four nuclear genes for which we present new primers. These are: CAD (1719 bp) DDC (708 bp), enolase (1149 bp), and PEPCK (1044 bp). The combined data set was analyzed using parsimony, maximum likelihood, and Bayesian methods. Statistical significance of the apparent non-monophyly of some taxonomic groups on our trees was evaluated using the approximately unbiased test of Shimodaira [Shimodaira, H. 2002. An approximately unbiased test of phylogenetic tree selection. Syst. Biol. 51(3), 492-508]. In accord with previous studies, we find moderate to strong support for monophyly of Chalcidoidea, a sister-group relationship of Mymaridae to the remainder of Chalcidoidea, and a relatively basal placement of Encarsia (Aphelinidae) within the latter. The 'pteromalid lineage' of families is generally recovered as monophyletic, but the hypothesis of monophyly for Pteromalidae, which appear paraphyletic with respect to all other families sampled in that lineage, is decisively rejected (P < 10(-14)). Within Pteromalidae, monophyly was strongly supported for nearly all tribes represented by multiple exemplars, and for two subfamilies. All other multiply-represented subfamilies appeared para- or polyphyletic in our trees, although monophyly was significantly rejected only for Miscogasterinae, Ormocerinae, and Colotrechninae. The limited resolution obtained in the analyses presented here reinforces the idea that reconstruction of pteromalid phylogeny is a difficult problem, possibly due to rapid radiation of many chalcidoid taxa. Initial phylogenetic comparisons of life history traits suggest that the ancestral chalcidoid was small-bodied and parasitized insect eggs.     

The pretarsus of salticid spiders

The pretarsus of Phidippus audax (Hentz) consists of two claws flexibly articulated to a central claw lever which is flanked on either side by a curved plate of tenent setae. The claw apparatus allows for retraction of the claws by means of a dorsal cuticular cable of the pretarsal levator, while extension involves the pull of the pretarsal depressor on a ventral cable attached to the claw lever. A series of slit sensilla are strategically situated on either side of this lever. The anterior and posterior claws of the pretarsus differ in the number and spacing of their constituent teeth. The claw tufts are composed of specialized setae which account for the mechanical traction of the foot-pads. Whorled and filamentous setae of the distal tarsus are associated with the pretarsus. Comparable structures are found on other salticids.     

特新蚤指名亚种幼虫的形态(英文)

本文详细描述了尚未报道的特新蚤指名亚种Neopsyllaspecialisspecialis幼虫形态。它与新蚤属已描述的5种或亚种幼虫的鉴别特征是：1-3胸节腹板上后排主鬃列长鬃外侧有2个小鬃;破卵器的长宽比例,大颚的齿数和齿形,前后头刚毛的数目和长度,肛梳刚毛和支柱毛的数目。作者观察到特新蚤指名亚种幼虫第10背板上有感器一对,并又观察了4科9种或亚种蚤幼虫和Bartkowska（1965,1972）,Kirjakova（1968）的描述,认为该特征可能是多毛蚤科幼虫的鉴别恃征之一。     

MORPHOLOGICAL DESCRIPTION ON THE LARVA OF NEOPSYLLA SPECIALIS SPECIALIS*

Abstract This paper deals in detail with the morphology of the larva of Neopsylla specialis specialis Jordan, 1932. It may be distinguished from other larvae of 5 species or subspecies of Neopsylla by two fine setae lying on outside of each posterior long seta on the ventral plates of the first to third thoracic segments, ratio of the length and width of the egg burster, number and shape of mandibular teeth, number and length of the setae in the anterior and posterior row on dorsal side of head, and number of the setae of anal comb and the strut setae. The sense organs on the 10th tergite are discussed.     

Peculiarities of the brain organization and fine structure in small insects related to miniaturization. 2. The smallest Hymenoptera (Mymaridae, Trichogrammatidae)

The organization and fine structure of the brain in the smallest parasitic wasps, Anaphes flavipes and Trichogramma evanescens, were studied using serial histological sections as well as TEM and computer-assisted 3D reconstructions. The data on the number and size of neurons in the brain of Mymaridae and Trichogrammatidae were obtained. They confirm and supplement the hypothesis about the factors limiting miniaturization of insects. The organization of the brain of the smallest parasitic wasps is compared with that of Hemiptarsenus sp. (Eulophidae), a large representative of Chalcidoidea. Some brain areas reveal strong allometry. The relative volume of the antennal lobes, lateral protocerebrum, and protocerebral bridge increases significantly as the body size decreases. Miniaturization is accompanied by an increase in the relative brain volume and changes in the spatial orientation of some brain structures. The number and size of neurons of A. flavipes and T. evanescens are significantly different from those of large representatives of Chalcidoidea, but similar to those of other tiny insects. Miniaturization of the nervous system is limited by the size of neurons and the diameter of axons.     

Ultrastructure and formation of hooded hooks in Capitella capitata (Annelida, Capitellida)

 The hooded hooks of Capitella capitata are aligned in a transverse row inside each neuro- and notopodial rim of the last thoracic and all abdominal setigers. Each seta consists of a rostrum, a capitium, the spines of which surmount the rostrum, and a long, sigmoid shaft or manubrium, towards which rostrum and capitial spines are curved. A thin hood, complete except for a subapical opening and a short, subrostral cleft, encloses the apical portions of the seta. Generally, the tip of the rostrum extends beyond the hood. The hood consists of an outer and an inner lamella, between which is a compartment loosely filled with fibrillar material. Hooded hooks are generated at the dorsal edge of the neuropodial rim and at the ventral edge of the notopodial rim during the entire life of C. capitata. Chaetogenesis starts in a small compartment surrounded by the basal chaetoblast and four follicle cells. Initially a group of microvilli emanating from the chaetoblast preforms the rostrum. Next, stout microvilli appear adrostrally, each preforming a spine of the capitium. When both structures have been formed, the longitudinal axis of the anlage shifts, because the actin filaments inside the microvilli reorientate and initiate formation of the manubrium. During this initial phase of chaetogenesis the anlage sinks into the chaetoblast, until the latter finally enwraps the anlage, except the tip of the rostrum. The chaetoblast now generates microvilli that face the new setal structures and preform the hood. During further development the microvilli separate into two layers, an inner and an outer one. The inner layer of microvilli merges with the manubrium prior to the outer layer. Addition of setal material occurs between the bases of the microvilli and elongates the manubrium until it extends beyond the epidermal surface. The microvilli, which have continuously been withdrawn from the seta during chaetogenesis, remain in the basal section. Specific morphogenetic and structural correspondence between the hooked setae of species of Maldanomorpha, Psammodrilida and Oweniida, the uncini of species of the Sabellida, Terebellida and Pogonophora, and the hooded hooks of species of Capitellidae justify the hypothesis that all these setae are homologous. This hypothesis implies the existence of a monophyletic group consisting of all polychaetous Annelida with such setae. Accepted: 16 December 1997     

华球角(虫兆)属Chinogastrura中国一新种(弹尾目:球角(虫兆)科)

本文讨论了华球角[虫兆]属并描述江苏1新种：五齿华球角[虫兆]Chinogastrura quinidentis,sp.nov．。该种与分布在中国和日本的Ch．duplwispinosa（Yosii）,1954最为接近,如具4个臀刺、相似的角后器和弹器的端节等,但在握弹器、弹器基和齿节以及触角上的毛序等方面有别于后者。 正模：♂,江苏南京南京大学校园,1990-Ⅱ-26,采集号8118,KennethA．Christiansen采;副模：2多♂♂和2♀♀,同正模。模式标本保存在南京大学生物科学与技术系。     

华球角属Chinogastrura中国一新种(弹尾目:球角科)

本文讨论了华球角     

Pretarsus structure in relation to climbing ability in the ants Brachyponera sennaarensis and Daceton armigerum

We studied the external and internal pretarsus structure of the ants Brachyponera sennaarensis and Daceton armigerum in relation to their very different climbing ability. B. sennaarensis is a ground-dwelling species that is not able to climb vertical smooth walls. They have a pair of straight pretarsal claws with an average claw tip angle of 56 degrees, while the ventral tarsal surface lacks fine hairs that touch the substrate. They have no adhesive pad on the vestigial arolium, while the arolium gland is very small. D. armigerum, on the other hand, is an arboreal and thus well-climbing species with a very strong grip on the substrate. Their pretarsal claws are very hooked, with a claw tip angle around 75 degrees. They have dense arrays of fine hairs on the ventral tarsal surface, a well-developed arolium and arolium gland. These clearly different morphological characteristics are in line with the opposite climbing performance of both species.     

Structure and function of the arolium of Mantophasmatodea (Insecta)

All species of the insect order Mantophasmatodea characteristically keep the 5th tarsomere and pretarsus (arolium plus two claws) turned upwards and off the substrate. The unusually large arolium was studied in two species of Mantophasmatodea using bright field light microscopy, reflection microscopy, fluorescence microscopy, TEM, SEM, and Cryo‐SEM. It contains an epithelial gland, numerous tracheoles, and nerves. The gland consists of enlarged epithelial cells with large nuclei, mitochondria, RER, golgi complexes, microtubules, and numerous secretion vesicles. Evidence for exocytosis of the vesicles into the gland reservoir between the epithelial gland and the thick cuticle could be observed. Cryo‐SEM revealed that the ventral side of the arolium and distal part of its dorsal side are covered with a liquid film. Fluid footprints of arolia of individuals walking on a glass plate also indicate the presence of secretory fluid on the arolium surface. Behavioral experiments using animals with ablated arolia showed that representatives of Mantophasmatodea do not need their arolia to detect and respond to vibratory communication signals nor to catch small to medium‐sized prey. Individuals with ablated arolia were not able to move upside down on a smooth glass plate. We conclude that Mantophasmatodea use their arolia for attachment when additional adhesion force is required (e.g. windy conditions, handling large prey, mating). They can bring their arolia in contact with the surface in a very fast reflex (18.0 ± 9.9 ms). The secretory fluid found on the surface is produced by the gland and transported to the outside, presumably through small pore channels, to enhance adhesion to the substrate. J. Morphol., 2009. © 2009 Wiley‐Liss, Inc.