Head anatomy of adult Sisyra terminalis (Insecta: Neuroptera: Sisyridae) – Functional adaptations and phylogenetic implications

The external and internal head anatomy of Sisyra terminalis is described in detail and compared with data from literature. A salivary pump consisting of a peculiar reservoir and a hitherto unknown muscle, M. ductus salivarii, is newly described for Neuroptera. The upward folded paraglossae form a secondary prolongation of the salivary system. These structures are discussed as functional adaptations for feeding on aphids and desiccated honeydew. In a phylogenetic analysis the basal position of the Sisyridae within Neuroptera is retrieved. The following new synapomorphies are postulated: (1) for Neuropterida, the presence of a M. submentomentalis and prepharyngeal ventral transverse muscles, and the absence of a M. submentopraementalis; (2) for Neuroptera and Sialidae, the presence of a mandibular gland; (3) for Neuroptera, the presence of four scapopedicellar muscles; (4) for Neuroptera exclusive Nevrorthidae and Sisyridae, the weakening of dorsal tentorial arms, the presence of a M. tentoriomandibularis medialis superior and the shifted origin of M. tentoriocardinalis.     

The larval head of Nevrorthidae and the phylogeny of Neuroptera (Insecta)

External and internal head structures of larvae of Nevrorthidae were described in detail. The results were compared to conditions found in other representatives of Neuroptera and the other two neuropterid orders. The cladistic analysis supported the monophyly of Neuroptera, Neuroptera exclusive of Nevrorthidae, Hemerobiiformia, and Myrmeleontiformia. Neuroptera exclusive of Nevrorthidae are supported by the formation of an undivided postmentum and the presence of cryptonephric Malpighian tubules. The highly specialized articulation of the neck (Rollengelenk) and the absence of a salivary duct are autapomorphies of Nevrorthidae. Ithonidae and Polystoechotidae form a clade and are the sister group of the remaining Hemerobiiformia, which are characterized by the complete lack of a gula and a terminal filament of the antenna. Within this lineage, a clade comprising Mantispidae, Dilaridae, Berothidae, and Rhachiberothidae is well supported. Larvae of Myrmeleontiformia are characterized by a complex transformation of head structures, with a hypostomal bridge, a small triangular gula, largely reduced maxillary grooves, and anteriorly shifted posterior tentorial grooves. The slender finger‐like mid‐dorsal apodeme is another autapomorphy of the group. Psychopsidae are placed as the sister group of the remaining Myrmeleontiformia, which are characterized by a conspicuous, protruding ocular region (often less distinct or even absent in Nemopteridae). Ascalaphidae are the sister group of Myrmeleontidae. Larvae of both families share the fusion of the tibia and tarsus in the hind leg. The larval characters analysed were not sufficient for full resolution of the myrmeleontiform and hemerobiiform lineages. The position of several families such as Osmylidae, Sisyridae, and Coniopterygidae remains uncertain. The results are in agreement with an aquatic ancestor of Neuroptera and secondarily acquired terrestrial habits within the lineage (Neuroptera exclusive of Nevrorthidae), and another invasion of the aquatic environment by Sisyridae. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 158 , 533–562.     

Phylogeny of the Neuropterida (Insecta: Holometabola)

The Neuropterida, with about 6500 known species — living fossils in a way — at the base of the Holometabola (as a sister group of the Coleoptera), comprise Raphidioptera (about 210 species, two families), Megaloptera (about 300 species, two families) and Neuroptera (6000 species, 17 families). Megaloptera + Neuroptera is argued vs. the traditional Raphidioptera + Megaloptera. Raphidioptera are undisputedly monophyletic. Monophyly of Megaloptera is the operational hypothesis, although occasionally questioned. Sucking tubes of the larvae are the most spectacular autapomorphy of Neuroptera. The construction of larval head capsules indicates three evolutionary lines: Nevrorthiformia, and Myrmeleontiformia + Hemerobiiformia. Traditional Myrmeleontiformia is Psychopsidae + (Nemopteridae + (Nymphidae + (Myrmeleontidae + Ascalaphidae))), the present approach is (Psychopsidae + Nemopteridae) + all other Myrmeleontiformia. Hemerobiiformia are based on the ‘maxillary head’ concept. The ithonid clade Ithonidae/Rapismatidae + Polystoechothidae and the dilarid clade Dilaridae + (Mantispidae + (Rhachiberothidae + Berothidae)) are based on robust criteria. Other relationships remain unclear: Hemerobiidae + Chrysopidae (on similarity) and the ‘early offshoot’ concept of coniopterygidae (on autapomorphies) should not be perpetuated. Chysopidae + Osmylidae and (Hemerobiidae + (Coniopterygidae + Sisyridae)) + dilarid clade are discussed. Aquatic larvae, regarded as independent apomorphies of megaloptera and neuropteran Nevrorthidae and Sisyridae for a long time, are re‐interpreted as a synapomorphy of Megaloptera + Neuroptera and thus plesiomorphic within these groups. Terrestrial larvae (with cryptonephry to solve osmotic problems) are consequently apomorphic. Aquatic Sisyridae with cryptonephry of a single malpighian tubule, is conflicting, but larvae may have become secondarily aquatic, after a terrestrial intermezzo.     

Cladistic analysis of Neuroptera and their systematic position within Neuropterida (Insecta: Holometabola: Neuropterida: Neuroptera)

A phylogenetic analysis of Neuroptera using thirty‐six predominantly morphological characters of adults and larvae is presented. This is the first computerized cladistic analysis at the ordinal level. It included nineteen species representing seventeen families of Neuroptera, three species representing two families (Sialidae and both subfamilies of Corydalidae) of Megaloptera, two species representing two families of Raphidioptera and as prime outgroup one species of a family of Coleoptera. Ten equally most parsimonious cladograms were found, of which one is selected and presented in detail. The results are discussed in light of recent results from mental phylogenetic cladograms. The suborders Nevrorthi‐ formia, Myrmeleontiformia and Hemerobiiformia received strong support, however Nevrorthiformia formed the adelphotaxon of Myrmeleontiformia + Hemerobiiformia (former sister group of Myrmeleontiformia only). In Myrmeleontiformia, the sister‐group relationships between Psychopsidae + Nemopteridae and Nymphidae + (Myrmeleontidae + Ascalaphidae) are corroborated. In Hemerobiiformia, Ithonidae + Polystoechotidae is confirmed as the sister group of the remaining families. Dilaridae + (Mantispidae + (Rhachiberothidae + Berothidae)), which has already been proposed, is confirmed. Chrysopidae + Osmylidae emerged as the sister group of a clade comprising Hemerobiidae + ((Coniopterygidae + Sisyridae) + (dilarid clade)). Despite the sister‐group relationship of Coniopterygidae + Sisyridae being only weakly supported, the position of Coniopterygidae within the higher Hemerobiiformia is corroborated. At the ordinal level, the analysis provided clear support for the hypothesis that Megaloptera + Neuroptera are sister groups, which upsets the conventional Megaloptera + Raphidioptera hypothesis.     

The larval head of Raphidia (Raphidioptera, Insecta) and its phylogenetic significance

External and internal head structures of larval representatives of Raphidiidae are described. The obtained data were compared to characters of other neuropterid larvae and to larval characters of representatives of other endopterygote lineages. Characters potentially relevant for phylogenetic reconstruction are listed and discussed. The larvae of Raphidioptera differ distinctly from other neuropterid larvae in their morphology. They are mainly characterised by autapomorphic and plesiomorphic character states and few features indicate systematic affinities with other groups. Endopterygote groundplan features maintained in Raphidioptera are the complete tentorium, the free labrum, the full set of labral muscles, the presence of four extrinsic antennal muscles, the three-segmented labial palpi, the presence of a full set of extrinsic maxillary and labial muscles, the presence of a salivarium, and possibly the high number of stemmata. Apomorphies likely correlated with predaceous habits are the long gula, the protracted maxillae, the longitudinal arrangement of extrinsic maxillary muscles, and the elongated prepharyngeal tube. Highly unusual, potentially autapomorphic features are the presence of a dorsal ligament of the tentorium and paired gland-like structures below the pharynx. A prognathous or very slightly inclined head and slender mandibles without mola are features shared by larvae of all orders of Neuropterida. The parallel-sided head is a potential synapomorphy of Raphidioptera and Megaloptera. A fully prognathous head with anteriorly shifted posterior tentorial grooves and the presence of a parietal ridge and a distinct neck region are features shared with Corydalidae. Characters of the larval head are not sufficient for a reliable placement of Raphidioptera.     

Mitochondrial phylogenomics illuminates the evolutionary history of Neuropterida

Neuroptera (lacewings) and allied orders Megaloptera (dobsonflies, alderflies) and Raphidioptera (snakeflies) are predatory insects and together make up the clade Neuropterida. The higher‐level relationships within Neuropterida have historically been widely disputed with multiple competing hypotheses. Moreover, the evolution of important biological innovations among various Neuropterida families, such as the origin, timing and direction of transitions between aquatic and terrestrial habitats of larvae, remains poorly understood. To investigate the origin and diversification of lacewings and their allies, we undertook phylogenetic analyses of mitochondrial genomes of all families of Neuropterida using Bayesian inference, maximum likelihood and maximum parsimony methods. We present a robust, fully resolved phylogeny and divergence time estimation for Neuropterida with strong statistical support for almost all nodes. Mitochondrial sequence data are typified by significant compositional heterogeneity across lineages, and parsimony and models assuming homogeneous rates did not recover Neuroptera as monophyletic. Only a model accounting for compositional heterogeneity (i.e. CAT‐GTR) recovered all orders of Neuropterida as monophyletic. Significant findings of the mitogenomic phylogeny include recovering Raphidioptera as sister to Megaloptera plus Neuroptera. The sister family of all other lacewings are the dusty‐wings (Coniopterygidae), rather than Nevrorthidae. Nevrorthidae are instead returned to their traditional position as the sister group of the spongilla‐flies (Sisyridae) and closely related to Osmylidae. Our divergence time analysis indicates that the Mesozoic was indeed a ‘golden age’ for lacewings, with most families of Neuropterida diverging during the Triassic and Jurassic and all extant families present by the Early Cretaceous. Based on ancestral character state reconstructions of larval habitat we evaluate competing hypotheses regarding the life style of early neuropteridan larvae as either aquatic or terrestrial.     

Phylogeny of Myrmeleontiformia based on larval morphology (Neuropterida: Neuroptera)

The suborder Myrmeleontiformia is a derived lineage of lacewings (Insecta: Neuroptera) including the families Psychopsidae, Nemopteridae, Nymphidae, Ascalaphidae and Myrmeleontidae. In particular, Myrmeleontidae (antlions) are the most diverse neuropteran family, representing a conspicuous component of the insect fauna of xeric environments. We present the first detailed quantitative phylogenetic analysis of Myrmeleontiformia, based on 107 larval morphological and behavioural characters for 36 genera whose larvae are known (including at least one representative of all the subfamilies of the suborder). Four related families were used as outgroups to polarize character states. Phylogenetic analyses were conducted using both parsimony and Bayesian methods. The reconstructions resulting from our analyses corroborate the monophyly of Myrmeleontiformia. Within this clade, Psychopsidae are recovered as the sister family to all the remaining taxa. Nemopteridae (including both subfamilies Nemopterinae and Crocinae) are recovered as monophyletic and sister to the clade comprising Nymphidae + (Myrmeleontidae + Ascalaphidae). Nymphidae consist of two well‐supported clades corresponding to the subfamilies Nymphinae and Myiodactylinae. Our results suggest that Ascalaphidae may not be monophyletic, as they collapse into an unresolved polytomy under the Bayesian analysis. In addition, the recovered phylogenetic relationships diverge from the traditional classification scheme for ascalaphids. Myrmeleontidae are reconstructed as monophyletic, with the subfamilies Stilbopteryginae, Palparinae and Myrmeleontinae. We retrieved a strongly supported clade comprising taxa with a fossorial habit of the preimaginal instars, which represents a major antlion radiation, also including the monophyletic pit‐trap building species.     

The larval head morphology of Xyela sp. (Xyelidae, Hymenoptera) and its phylogenetic implications

Larval head structures of Xyela sp. are described in detail. The characters are compared to conditions found in larvae of other groups of Hymenoptera and Endopterygota. Like other symphytan larvae the immature stages of Xyelidae are mainly characterized by presumably plesiomorphic features of the head. The head sutures are well developed and all parts of the tentorium are present. The labrum is free and a complete set of labral muscles is present. The maxillae are in a retracted position. In contrast to other hymenopteran larvae Xyela possesses a clypeofrontal suture, a comparatively long antenna and three well‐developed antennal muscles. Apomorphic features of Xyela are the absence of muscles associated with the salivarium and the complete absence of Musculus craniocardinalis. A clade comprising Orussidae and Apocrita is supported by the unsegmented maxillary and labial palps and the absence of the lacinia. Six potential autapomorphies for the Hymenoptera were revealed: (1) the caudal tentorial apodeme, (2) the bifurcated tendon of Musculus craniomandibularus internus, (3) the lateral lobe of the cardo, (4) the origin of M. tentoriohypopharyngalis from the posterior head capsule, (5) the exceptionally strong prepharyngo‐pharyngeal longitudinal muscle and (6) the longitudinal muscle of the silk press. The maxillolabial complex, the vestigial M. craniocardinalis and a distinctly developed labio‐hypopharyngeal lobe bearing the opening of the salivary duct are potential synapomorphies of Hymenoptera and Mecopterida. The globular, orthognathous head capsule, the modified compound eyes, the occipital furrow and the X‐shaped tentorium are features with unclear polarity shared by Hymenoptera and Mecoptera.     

Head morphology of <Emphasis Type="Italic">Osmylus fulvicephalus</Emphasis> (Osmylidae,Neuroptera) and its phylogenetic implications

External and internal head structures of Osmylus fulvicephalus were examined and described in detail. Exo- and endoskeleton, musculature, elements of the central nervous system and tracheae are compared to conditions found in other groups of Neuropterida and other endopterygote lineages. Thirty-six adult cephalic characters were compiled, combined in a datamatrix with 64 characters of the larval head, and analysed cladistically. Mainly because many data on adults remain missing, most branches in the cladogram are mostly or exclusively supported by larval features. The shortening of the mesal mandibular wall and the resulting anterior shift of the adductor tendon possibly constitute an adult groundplan apomorphy of Neuropterida. Raphidioptera and Megaloptera share distinct prognathism and the presence of a sclerotised gula. However, the orthognathous head and the absence of a gula resulted as autapomorphies of Neuroptera in our analyses. Further potential autapomorphies are the asymmetry of the mandibles as well as the respective presence of dorsolateral furrows on the head capsule, of a shovel-like extension on the ventral mandibular cutting edge, and of a row of stiff hairs on the mandible’s ventral surface. The systematic affinities of Osmylidae remain ambiguous. Osmylus is mainly characterised by plesiomorphic features of the adult head such as a complete endoskeleton, long filiform antennae, largely unmodified orthopteroid mouthparts, and particularly the nearly complete set of muscles. The placement with a clade also comprising Hemerobiidae and Chrysopidae is poorly supported. The presence of a dense vestiture of long microtrichia on the distal galeomere resulted as a synapomorphy of the three families. An apparent plesiomorphy preserved in Osmylus but absent in all other groups of Neuroptera is the presence of well developed ocelli. The present study underlines the severe shortage of detailed morphological data on the adults. Intensive study of adult structures is required for a solid reconstruction of the phylogeny of Neuropterida, especially of the hemerobiform lineage of Neuroptera.     

Global diversity of dobsonflies,fishflies, and alderflies (Megaloptera; Insecta) and spongillaflies,nevrorthids, and osmylids (Neuroptera; Insecta) in freshwater

The insect orders Megaloptera and Neuroptera are closely related members of the superorder Neuropterida, a relict lineage of holometabolous insects that also includes the Raphidoptera. Megaloptera, composed of the families Sialidae and Corydalidae (including subfamilies Chauliodinae and Corydalinae), has fully aquatic larvae that occur in a wide variety of lotic and lentic habitats, including temporary streams. In total, 2 of 17 families of Neuroptera have aquatic larvae: Nevrorthidae live in the benthos of fast-flowing streams and Sisyridae reside on freshwater sponges. A third family of Neuroptera, Osmylidae, contains some water-dependent species that reside under leaves and rocks along the margins of waterbodies. We recognize 328 extant, described species of Megaloptera (composed of 116 species of Chauliodinae, 131 species of Corydalinae, and 81 species of Sialidae) and 73 species of aquatic Neuroptera (composed of 12 species of Nevrorthidae and 61 species of Sisyridae). Additionally, we estimate that 45 species of Osmylidae are water-dependent, although the ecology of this group is poorly understood. Chauliodinae and Corydalidae are both found in the New World, the Oriental region, and South Africa, but are absent from Europe, the Middle East, Central Asia, tropical Africa, and boreal regions. Chauliodinae is quite speciose in Australia, whereas Corydalinae is absent. Sialidae is most speciose in temperate regions, and is absent from tropical Africa and portions of the Oriental region. Sisyridae and Osmylidae are nearly cosmopolitan, but the relict family Nevrorthidae is limited to Japan, the Mediterranean, and Australia. The discovery of many new species in recent years, particularly among Corydalidae in the Neotropics and China, suggests that our knowledge of aquatic neuropterid diversity is far from complete. Guest editors: E. V. Balian, C. Lévêque, H. Segers and K. Martens Freshwater Animal Diversity Assessment     

The larval head of Agathiphaga (Lepidoptera, Agathiphagidae) and the lepidopteran ground plan

Abstract. The larval head of Agathiphaga vitiensis is described. There is a complete hypostomal bridge but no hypostomal ridges. Adfrontal ridges and distinct ecdysial lines are absent. There are two vestigial stemmata (without lenses) on each side. The antenna is one-segmented. All ‘typical lepidopteran’ head setae have been identified. The corporotentorium is very slender; dorsal tentorial arms are present. Intrinsic labral muscles are lacking. The mandible has retained a tentorial muscle. The maxilla is without a discrete cardo and has but a single endite lobe; ‘intrinsic maxillary muscles’ and the ‘cranial flexor of the dististipes’ are lacking. The postlabium is undivided and without setae, the labial palp is one-segmented and the lateral prelabio-hypopharyngeal sclerotization is continued into an oral arm. Some of the ventral pharyngeal dilators arise on the tentorium; mouth-angle retractors and dorsal post-cerebral pharynx dilators are absent. The two brain lobes have almost parallel long axes and are united by a narrow (almost pure neuropile) bridge. The corpora cardiaca and callata are contiguous. The aorta is an open gutter in front of the retrocerebral complex. Available evidence on the ground plan structure of the lepidopteran larval head is reviewed. The ancestral head supposedly was prognathous and was autapomorphic in having the cranio-cardinal articulation far behind the mandible; it had a complete hypostomal bridge but neither hypostomal nor adfrontal ridges, its tentorium was probably stout and with dorsal arms. Paulus & Schmid (1978, Z. zool. Syst. EvolForsch. 16) described a lepidopteran/trichopteran synapomorphy in stemma structure. A tentative table of homologies between cranial setae in Lepidoptera and Trichoptera is presented; it differs considerably from the scheme of Williams & Wiggins (1981, Proc. 3rd Symp. Trichopt.). The mouth parts and their musculature must have been overall very primitive for a panorpid larva, but the number of maxillary palp segments was reduced (three). The ‘dististipes’sensu Hinton is considered to consist of complexly fused parts of the stipes and basal palp segments. The cephalic stomodaeum must have possessed all primitive groups of extrinsic muscles. The incomplete available information on Micropterigidae impedes reconstruction of some details of the lepidopteran ground plan. Larval head structures support the monophyly of an entity comprising the Agathiphagidae + Heterobathmiidae + Glossata. There is one suite of derived characters shared by Heterobathmiidae and Agathiphagidae only and another shared by Heterobathmiidae and the Glossata only; one of these must represent parallelisms.     

The larval morphology of the spongefly Sisyra nigra (Retzius, 1783) (Neuroptera: Sisyridae)

The morphology of mature larvae of Sisyra nigra was studied and documented with a broad spectrum of techniques. Special emphasis is on the cephalic anatomy and on the digestive tract. Cephalic structures are highly modified, with numerous autapomorphic conditions, including a globular head capsule, an extended area with large cornea lenses, a massive tentorium, a strongly developed prepharyngeal pumping apparatus with a horizontal arrangement of dilators, a sharp bend between the prepharynx and pharynx, and an unusual filter apparatus at the entrance of the large crop. The thoracic and abdominal muscle sets, and the legs are largely unmodified. Postcephalic apomorphies are conspicuous tergal setiferous tubercles, trifid setiferous pleural projections, single pretarsal claws, zigzag-shaped abdominal tracheal gills, and a dense vestiture of setae on the terminal abdominal segments. Mandibulo-maxillary stylets curved outwards are an unusual apomorphy also found in the semiaquatic larvae of Osmylidae. Semiaquatic or aquatic habits and secondarily multisegmented antennae are potential synapomorphies of these two groups and Nevrorthidae (Osmyloidea). A sistergroup relationship between Sisyridae and Nevrorthidae suggests that fully aquatic habits of larvae may be a synapomorphy of both families. A specialized terminal antennal seta is a potential groundplan apomorphy of Neuroptera, with secondary loss in Nevrorthidae and Ithonidae + Myrmeleontiformia, respectively. A trumpet-shaped empodium is likely an apomorphy of Neuroptera excluding Coniopterygidae and Osmyloidea, and the secondary loss an apomorphy of Ithonidae on one hand, and Myrmeleontiformia excl. Psychopsidae on the other.     

Phylogenetic relevance of the genital sclerites of Neuropterida (Insecta: Holometabola)

Abstract Segment 9 of male Raphidioptera, comprising tergite, sternite, gonocoxites, gonostyli and gonapophyses, is a benchmark for homologies in the male and female terminalia of the three Neuropterida orders Raphidioptera, Megaloptera and Neuroptera. The segments relating to genitalia are 9, 10 and 11 in males and 7, 8 and 9 in females. Results from holomorphological and recent molecular cladistic analyses of Neuropterida agree in supporting the sister‐group relationships between: (1) the Raphidioptera and the clade Megaloptera + Neuroptera, and (2) the suborder Nevrorthiformia and all other Neuroptera. The main discrepancy between the results of these studies is the nonmonophyly of the suborder Hemerobiiformia in the molecular analysis. The monophyly of the Megaloptera (which has been repeatedly questioned) is further corroborated by a hitherto overlooked ground pattern autapomorphy: the presence of eversible sacs within the complex of the fused gonocoxites 11 in Corydalidae and Sialidae. The recently discovered paired complex of gonocoxites 10 (parameres) in Nipponeurorthus (Nevrorthidae) indicates that the curious apex of sternite 9 of Nevrorthus and Austroneurorthus is the amalgamation of the sclerites of gonocoxites 10 with sternite 9, interpreted as synapomorphic. In the molecular study, the Nevrorthidae, Sisyridae and Osmylidae branch off in consecutive splitting events, a result that is supported by the analysis of male genital sclerites reported here. Extraordinary parallel apomorphies (e.g. excessive enlargement and modification of gonocoxites 10 ending in a thread‐like ‘penisfilum’) in derived representatives of Coniopterygidae, Berothidae, Rhachiberothidae and Mantispidae corroborate the dilarid clade of the morphological analysis and leads us to hypothesize a sister‐group relationship of the Coniopterygidae with the dilarid clade. A re‐interpretation of the tignum of Chrysopidae as gonocoxites 11 means that the structure previously called the gonarcus represents the fused gonocoxites 9. In Hemerobiidae, the corresponding sclerite is consequently also homologized as fused gonocoxites 9. The enlargement of the lateral wings of the gonocoxites in both families is interpreted as a synapomorphy. Excessive enlargement of gonostyli 11 in the Polystoechotid clade and Myrmeleontiformia supports a sister‐group relationship of these two clades. The occurrence of certain serial homologues of female genitalia structures (gonocoxites and gonapophyses), such as the digitiform processus together with the flat appendices in segment 8 of certain Myrmeleontidae, or the wart‐like processus together with the flat circular sclerites in segment 7 of certain Berothidae, as well as the presence of gonocoxites 8 as pseudosternites in certain Nemopteridae and Coniopterygidae, are probably character reversals. The digitiform processus of tergite 9 (pseudogonocoxites) in Rhachiberothidae and Austroberothella (Berothidae) are either independently developed acquisitions with a function in oviposition, or are homologous sclerites, possibly of epipleurite origin.     

Tentorial mobility in centipedes (Chilopoda) revisited: 3D reconstruction of the mandibulo-tentorial musculature of Geophilomorpha

Mandibular mechanisms in Geophilomorpha are revised based on three-dimensional reconstructions of the mandibulo-tentorial complex and its muscular equipment in Dicellophilus carniolensis (Placodesmata) and Hydroschendyla submarina (Adesmata). Tentorial structure compares closely in the two species and homologies can be proposed for the 14/17 muscles that attach to the tentorium. Both species retain homologues of muscles that in other Pleurostigmophora are traditionally thought to cause swinging movements of the tentorium that complement the mobility of the mandibles. Although the original set of tentorial muscles is simplified in Geophilomorpha, the arrangement of the preserved homologues conforms to a system of six degrees of freedom of movement, as in non-geophilomorph Pleurostigmophora. A simplification of the mandibular muscles is confirmed for Geophilomorpha, but our results reject absence of muscles that in other Pleurostigmophora primarily support see-saw movements of the mandibles. In the construction of the tentorium, paralabial sclerites seem to be involved in neither Placodesmata nor Adesmata, and we propose their loss in Geophilomorpha as a whole. Current insights on the tentorial skeleton and its musculature permit two alternative conclusions on their transformation in Geophilomorpha: either tentorial mobility is primarily maintained in both Placodesmata and Adesmata (contrary to Manton’s arguments for immobility), or the traditional assumption of the tentorium as being mobile is a misinterpretation for Pleurostigmophora as a whole.     

Head anatomy of adult Coniopteryx pygmaea : Effects of miniaturization and the systematic position of Coniopterygidae (Insecta: Neuroptera)

External and internal head structures of adult Coniopteryx pygmaea Enderlein, 1906, one of the smallest known lacewings, are described in detail for the first time. Possible effects of miniaturization and two hypotheses on the phylogenetic position of Coniopterygidae are evaluated and compared with data from literature. Several convergent modifications in C. pygmaea and other miniaturized insect species are outlined, e.g., a relative increase in the size of the brain, simplification of the tracheal system with respect to the number of tracheae, and reduction of the number of ommatidia and diameter of the facets. Further, the ocular ridge is bell-shaped and countersunk into the head capsule. The cuticle is weakly sclerotized and equipped with wax glands which are unique in Neuroptera. The total number of muscles is not affected by miniaturization. The phylogenetic analysis yields Coniopterygidae as sistergroup to the dilarid clade based on one larval character, the shape of the stylets. The enforced basal position of Coniopterygidae is supported by one disputable synapomorphy of the remaining Neuroptera, the presence of paraglossae in adults.     

Macroevolutionary consequences of developmental mode in temnopleurid echinoids from the Tertiary of southern Australia

Abstract Taxonomic revision and cladistic analysis of a morphological dataset for Australian Tertiary temnopleurids resolve the phylogeny of the group and allow the testing of a series of hypotheses about the evolution of larval development and consequences of changes in development. Australian Tertiary temnopleurids encompass all three major developmental types found in marine invertebrates (planktotrophy, lecithotrophy, and brooding). Planktotrophy is plesiomorphic for this clade, and nonplanktotrophic larval development evolved independently at least three times during the Tertiary. The change to a nonplanktotrophic mode of larval development is unidirectional with no evidence of reversal. In addition, there is no evidence of an ordered transformation series from planktotrophy through planktonic lecithotrophy to brooding. In common with previous studies of other invertebrate groups, analysis of the raw data suggests that nonplanktotrophic taxa within this clade have significantly shorter species longevities, more restricted geographic ranges and higher speciation rates than taxa with planktotrophic development. However, analysis using phylogenetically independent contrasts is unable to confirm that the stratigraphic and geographic patterns are unbiased by the phylogenetic relationships of the included taxa.     

Phylogeny of the Neuropterida: a first molecular approach

Abstract. In a first molecular approach specially dedicated to examining the phylogeny of the Neuropterida, two nuclear and two mitochondrial genes were tested: 18S rRNA, translation elongation factor‐1α, cytochrome c oxidase subunit 3 and 16S rRNA. Molecular results are discussed in the light of a previous holomorphological cladistic analysis. The hypothesis of a sister‐group relationship Raphidioptera + (Neuroptera + Megaloptera) put forward in recent morphological analyses is supported by our data, which is in contrast to the traditional view (Raphidioptera + Megaloptera) + Neuroptera. Furthermore, the Nevrorthidae (constituting the suborder Nevrorthiformia) as a sister group of all other Neuroptera is confirmed. The disruption of the suborder Hemerobiiformia is the most conflicting result of the molecular analysis. Sisyridae and Osmylidae do not cluster within Hemerobiiformia, but represent two distinct and widely separated branches. The remaining Hemerobiiformia emerge as the sister group of the suborder Myrmeleontiformia, which is once more confirmed as monophyletic. Among the genes tested, cytochrome c oxidase subunit 3 proved to be most potent for resolving the phylogenetic relationships among Neuropterida. The nuclear gene for the ribosomal 18S rRNA is too conserved within the alignable regions, whereas the variable sections are too divergent to be applicable within this evolutionary time frame. The elongation factor‐1α gene proved to exist in more than one copy in Neuropterida, and thus is not applicable in the present state of knowledge. With respect to the mitochondrial sequences (cytochrome c oxidase subunit 3, 16S rRNA), saturation impedes the unambiguous resolution of deeper nodes. Apparently, due to early diversification of the heterogeneous Neuroptera, phylogenetic analysis of this group remains a challenge with respect to selection of the proper genes and mutatis mutandis the morphological approach.     

A phylogeny of the families of Scarabaeoidea (Coleoptera)

Abstract. A study, based on examination of thirteen scarabaeoid families, was made of 134 adult and larval characters from the following character suites: 105 adult characters of the antennae, eye, epipharynx, mandible, maxillae, labium, tentorium, trochantin, procoxae, mesocoxae, mesothoracic spiracles, hind wing articulation, hind wing base, hind wing venation, hind wing folding, abdominal sternites, abdominal spiracles, male genitalia, ovarioles and karyotype; twenty larval characters of the antennae, fronto-clypeal suture, stemmata, labial palpi, maxillae, mandibles, legs, stridulatory apparatus, spiracles and ecdysial process; and nine adult and larval biological characters. In order to assess the reliability of different characters in resolving scarabaeoid family relationships, six data sets were subjected to cladistic analysis: the total evidence character set (134 characters), restricted adult character set (thirty-two characters, not including those of the wings), wing character set (seventy-three characters), larval character set (twenty characters), biological character set (nine characters) and re-coded Howden (1982) character set (thirty-nine characters). The complete character set and wing character set both produced phylograms with all nodes resolved; the restricted adult data set, larval data set, Howden (1982) data set and biological data set produced phylograms with diminishing levels of node resolution. The reconstructed phylogeny, from the preferred phylogram of the total evidence character set, shows that the Scarabaeoidea comprises three major lineages; a glaresid, passalid and scarabaeid lineage. The glaresid lineage consists only of the Glaresidae. The passalid lineage comprises two major lines; a glaphyrid line (containing Glaphyridae, Passalidae, Lucanidae, Diphyllostomatidae, Trogidae, Bolboceratidae and Pleocomidae) and a geotrupid line (containing Geotrupidae, Ochodaeidae, Ceratocanthidae and Hybosoridae). The scarabaeid lineage contains those taxa traditionally included within the Scarabaeidae (Aphodiinae, Scarabaeinae, Orphninae, Melolonthinae, Acoma, Chasmatopterinae, Hopliinae, Oncerinae, Rutelinae, Dynastinae, Trichiinae, Cetoniinae and Valginae).