The occurrence of facultative paedomorphosis in a lacustrine population of the Pyrenean newt (Calotriton asper): morphology and age structure

Facultative paedomorphosis is a common polyphenism in newts where two alternative phenotypes can coexist: metamorphs and paedomorphs (mature with larval traits, i.e. retaining gills). This phenomenon has been reported in some lacustrine populations of the Pyrenean newt (Calotriton asper). The morphology and life-history traits were studied in a lacustrine population of this species with the occurrence of facultative paedomorphosis. The results showed that 24.3% of adults retained gills at different levels of reabsorption and had a smoother skin compared with the other populations, which were fully metamorphic. The body size and shape showed significant sexual differences, with males being larger than females. The presence of paedomorphic traits also affected the body size and shape, revealing a complex pattern of growth in which metamorphic adults were larger than paedomorphs. The age structure was different between sexes, with a median age of 10.5 and 7 years and longevity of 19 and 14 years in males and females, respectively. Considering each sex separately, the age structure was not significantly different between metamorphic and paedomorphic newts. In addition, metamorphosed and branchiate juveniles were found with a maximum age of 13 and 20 years, respectively. Remarkably, long-lived larvae with an exceptional individual of 18 years were found, which has not previously been reported in any other newt species. The mechanisms that can explain the evolution of paedomorphosis are complex and comprise the interaction of multiple factors related to the cost of reproduction and growth.     

The saws of sawflies: exploring the morphology of the ovipositor in Tenthredinoidea (Insecta: Hymenoptera), with emphasis on Nematinae

The variation in ovipositor sculpture and additional features of the ovipositor apparatus in Tenthredinoidea is explored. Two outgroups and 85 species of tenthredinoids were examined, the emphasis of the taxon sampling being on Nematinae. Twenty-four morphological characters where scored and the data set was analysed under different weighting conditions. The topologies derived from analysing the character set in TNT are poorly resolved and highly unstable when analytical settings are changed. Only a few clades, the Tenthredinoidea s. str., the Diprionidae, the Cimbicidae and the Argidae + Pergidae are consistently retrieved. The functional implications of the variation in ovipositor morphology within Tenthredinidae is discussed in relation to the qualities of the host plant, e.g. the hardness and the depth of penetration in plant tissue.     

Comparative larval morphology of the European bone-skippers,Thyreophora cynophila (Panzer, 1798) and Centrophlebomyia furcata (Fabricius, 1794) (Diptera: Piophilidae), with notes on their coexistence and natural history

Considered at times as extinct, the European bone-skippers Thyreophora cynophila and Centrophlebomyia furcata (Diptera: Piophilidae) have been recently rediscovered in Spain, coexisting in some areas. Nevertheless, apart from their typical association with big mammal carcasses, little is known about them and the other species of subtribe Thyreophorina. In the present paper, the larval morphology of T. cynophila is described for the first time and compared with that of C. furcata. The morphology of cephalopharyngeal skeleton, the number and arrangement of the spines of ventral creeping welts, and the morphology and presence or absence of tubercles in the two last segments of the body, are the main characters allowing for larval identification of both species. Some preliminary field and laboratory observations on the behaviour and life cycle of the two species are also provided.     

Observations on the morphology and classification of weevils (Coleoptera,Curculionoidea) with a key to major groups

A brief account of the present state of weevil taxonomy is followed by a detailed study of certain structures used in their classification, namely the venter, abdominal tergites, sternite 8 of the male, apex of the hind tibia and deciduous mandibular processes. A key to some 50 families and subfamilies of Curculionoidea is followed by a list of family-group taxa. The following changes are made: Brachyceridae, Erirhinidae, Cryptolaryngidae and Raymondionymidae are promoted to family rank from Curculionidae; Antliarhininae is demoted to a subfamily of Brentidae, and Allocoryninae to a subfamily of Oxycorynidae; Coptonotini is demoted to a tribe of Curculionidae-Scolytinae; Carinae, Subfam. n. is erected for Car Blackburn (genus incertae sedis) is Belidae; Dinomorphini is demoted to a tribe of Molytinae and Brachyceropsidinae is revived from synonymy with Dinomorphinae (Curculionidae); Brachyderini, Eremnini, Otiorhynchini and Sitonini are demoted to tribes of Entiminae; Desmidophorinae is transferred from Brentidae to Brachyceridae; Ocladiini is promoted to a tribe of Desmidophorinae (from Curculionidae-Cryptorhynchinae); Campyloscelini (including Phaenomerina) is transferred from Rhynchophoridae to Curculionidae-Zygopinae; Carphodicticinae is promoted to subfamily rank and transferred from Curculionidae-Scolytinae to Platypodidae; Perieges Schönherr is transferred from Curculionidae-Thecesterninae to Cryptolaryngidae and Agriochaeta Pascoe from Cryptorhynchinae to Hyperinae (Curculionidae); Schedlarius Wood and Mecopelmus Blackman are transferred from Coptonotidae to Platypodidae.     

The tortoise caterpillar: carnivory and armoured larval morphology of the metalmark butterfly Pachythone xanthe (Lepidoptera: Riodinidae)

ABSTRACT

The natural history and morphology of the later instars and pupa of the metalmark butterfly Pachythone xanthe H. Bates are described and illustrated for the first time. The caterpillars are myrmecophilous and carnivorous, feeding on scale insects (Hemiptera: Coccoidea) tended by Azteca cf. chartifex Forel (Formicidae: Dolichoderinae) ants and appear to be physically shielded from potential ant attacks by a carapace-like body that protects the head and appendages. In addition, the larvae present several types of specialised setae and ant-organs such as perforated cupola organs, glandular openings and functional tentacle nectary organs that may be related to appeasement of aggressive ant behaviour. Our results reveal the first detailed life cycle data for the Pachythonina subtribe and record a new independent origin of carnivory in Riodinidae.     

Reproduction and morphology of Polydorella (Polychaeta: Spionidae), including the description of a new species from the Philippines

A new spionid polychaete, Polydorella kamakamai, associated with sponges is described from the Philippines. Polydorella kamakamai is characterized by acicular neurosetae in segments 2–7, a fifth segment containing a ventral row of spines with digitiform bosses, and lack of branchiae. As in all members of the genus, P. kamakamai undergoes asexual reproduction via paratomy; the process of paratomy is examined through scanning electron and light microscopy. This species exhibits a growth zone following segment 10, leading to the production of stolon individuals budding from the stock individual; five or more individuals can thus be formed in a single chain. Paratomic division typically occurs in chains containing four to five individuals and as a result colonies are dominated by chains of two individuals. Sexual reproduction is documented for only the second time in the genus; P. kamakamai produces eggs in segments 13–15. Asexual reproduction and fine morphological structure of the ventral spines of the fifth segment are examined by SEM in P. dawydoffi and P. stolonifera. Polydorella dawydoffi is recorded for the first time from the Philippines and the Red Sea and these are compared to type specimens from Vietnam. The ventral spines of P. dawydoffi contain eight or nine rounded or pointed teeth along the apical end and a capillary extension not previously observed with light microscopy. Notes on feeding biology, parasitism by copepods, and a discussion of the evolutionary relationships of Polydorella and other polydorids are provided.     

Study of the external morphology of Leptodora kindtii Focke, 1844 (Crustacea: Branchiopoda: Haplopoda), with notes on its relation to Cladocera and on conspecificity of populations of the species over the Eurasian range

Leptodora kindtii is a peculiar carnivorous crustacean widely distributed and occupying a prominent position in the freshwater planktonic communities. This species was originally found and described in the 1840–1860s and since then it has been a subject of numerous studies, morphological, embryological, behavioural, and ecological, which elucidated various aspects of its body structure and mode of life. Nevertheless, analysis of the literature and personal investigation of material on the species have led to the conclusion that the morphology of the species was not studied properly and the previous data might be incorrect and inconsistent, which obstructed proper understanding of its phylogeny, taxonomic position, and habits. In the present investigation, the external morphology of L. kindtii is described and analysed in detail, from comparative morphological and eco‐morphological aspects. Also, the morphological features of representatives of the species from different populations over the vast area of its Eurasian range have been studied with respect to their intra‐ and interpopulational variability and taxonomic significance. It has been shown that the majority of populations of L. kindtii from Europe to the Far East of Russia do not display any significant morphological differences, which testifies to their conspecificity. Only a small set of adult specimens from Lake Bolon (the Amur River basin, Far East of Russia) differed considerably from others in their small size and body proportions which implies the occurrence of another species of the genus in this region to be studied and validated in the future together with the enigmatic cave species L. pellucida Josef. In spite of high morphological peculiarity, L. kindtii possesses a number of “core” characteristics, which undoubtedly show its close relationship with other mostly small branchiopods (Ctenopoda, Anomopoda, Onychopoda) traditionally united in the taxon Cladocera whose validity has also been supported by modern molecular‐genetic studies.     

Neosclerocalyptus spp. (Cingulata: Glyptodontidae: Hoplophorini): cranial morphology and palaeoenvironments along the changing Quaternary

We propose that the particular high latitudinal distribution of Neosclerocalyptus (Glyptodontidae) and the cyclic nature of the Pleistocene glacial–interglacial events were factors that probably stimulated morphological evolution of its fronto-nasal sinuses, a feature unique among glyptodonts. The distributions of the species, and the majority of its records, are associated with sediments related to arid and semiarid environments. Four species are recognized during the last million years in southern South America. The first record of Neosclerocalyptus (N. pseudornatus) coincides with the “Great Patagonian Glaciation” and shows the lowest grade of pneumatization on its skull. Neosclerocalyptus paskoensis (the most derived species), limited to Oxygen Isotopic Stage 2, shows the greatest development of fronto-nasal pneumatization. The restricted geographic range of Neosclerocalyptus, the possible absence of geographic barriers during the Pleistocene, and the absence of cases of sympatry, allow us to speculate the existence of a single continuous lineage of successive species, showing an anagenetic process.     

The evolutionary and biomechanical implications of snout and proboscis morphology in Caenogastropoda (Mollusca: Gastropoda)

The caenogastropod proboscis is a complex morphological adaptation to a carnivorous diet. This comparative morphological investigation of proboscis and snout anatomy in Caenogastropoda shows that there is undescribed diversity in both snout/proboscis wall composition and introversion/retraction musculature. There is morphological evidence which suggests that a proboscis evolved separately in at least four separate caenogastropod groups, each characterized by the presence of novel retractor muscles and different modifications of plesiomorphic “aortic muscles”. The biomechanical operation of the proboscis and snout utilizes a hydrostatic skeleton, but several higher caenogastropods have evolved a complex muscular hydrostat in the snout/proboscis wall which may mitigate the need to isolate the proboscis haemocoel during proboscis eversion.     

Reproductive aspects of Leptodactytus hylaedactylus (Anura: Leptodactylidae), a member of the Leptodactylus marmoratus species group,with a description of tadpoles and calls

In this paper we describe some aspects of the reproductive biology of Leptodactylus hylaedactylus from open areas of Central Amazonia, Brazil. We describe the calling site, reproductive season, daily pattern of calling activity, chamber structure, vocalizations and tadpole morphology. Males of Leptodactylus hylaedactylus called amidst grasses and bushes in open and urban areas, throughout the year, and a greater number of males were heard in the period from 16:00 to 20:00 h. The eggs are deposited in underground chambers, which are spherical or elliptical. Larval development occurs inside the chambers. Two types of vocalizations were detected, the advertisement and the territorial call. The advertisement call of the species studied herein differs from other calls described for L. hylaedactylus from other localities of Brazil, but is very similar to that described from Peru. Tadpole morphology is similar to that described from individuals in French Guiana.     

Taxonomy and ecology of the porcellanid crab Polyonyx cometes Walker, 1887 (Crustacea: Decapoda), with description of a new genus

The taxonomy of the rare porcellanid crab, Polyonyx cometes Walker, 1887 (Crustacea Decapoda), is reconsidered in the light of fresh material from Singapore, as well as the newly obtained first zoeal stage. Polyonyx cometes possesses numerous adult and larval characters which warrant the establishment of a new genus for the species. The species is confirmed as a commensal of the worm Chaetopterus (Annelida, Polychaeta).     

Mating behaviour in the bees,Dieunomia heteropoda and Nomia tetrazonata,with a review of courtship in Nomiinae (Hymenoptera: Halictidae)

Males of many bees in the subfamily Nomiinae (Halictidae) have numerous secondary sexual characters, which provide much systematic information. Similarly, the use of these structures by males during sexual behaviour may provide useful characters, but the courtship and copulatory behaviour of most of these bees is not known. Structures and behaviour used for courtship and mating are described for two species of nomiine bees, Dieunomia heteropoda and Nomia tetrazonata, along with brief observations of mating in a parasitic bee, Triepeolus verbesinae (Apidae: Nomadinae). A review of mating behaviour within the Nomiinae shows no obvious phyletic patterns, based upon present limited knowledge. The species-specific nature of the male secondary sexual characters suggests they may have evolved in the context of sexual selection, but behavioural data from populations of additional species are needed to evaluate the hypothesis adequately.     

Nest structure and all stages of the long-cheeked yellow jacket Dolichovespula intermedia Birula (Hymenoptera: Vespidae)

Nest structure, morphology of all stages and behaviour have contributed to the phylogenetic and taxonomic studies of social vespids. Two aerial nests of Dolichovespula intermedia were discovered in China. The morphology of the three castes, the five larval instars, and the nest structure of D. intermedia Birula, are described in detail and illustrated. The presence of only one campaniform sensillum above each labial palp and the dense minute spicules on the posterior gena found in D. intermedia larvae are mentioned here for the first time for Dolichovespula. The identification characters between D. intermedia and Dolichovespula sylvestris are briefly discussed.     

The morphology and biology of Pterodunga mirabile Daccordi,an unusual subsocial Chrysomeline (Coleoptera: Chrysomelidae)

New information is provided on the morphology and biology of the Australian leaf‐beetle Pterodunga mirabile Daccordi. This species is unusual in the Chrysomelinae for the following features: adult with deeply grooved prothoracic hypopleuron, laterally pointed elytral margins, concealed mesoventrite and fused abdominal ventrites; female ovoviviparous and without spermatheca; first‐instar larva with lappet‐like sclerites; maternal care; host plant in the Proteaceae. The systematic position and conservation status of Pterodunga are discussed. Maternal care in the Chrysomelinae and Proteaceae‐feeding in the Chrysomelidae are reviewed. The first record of maternal care in Chrysomelinae, for Labidomera suturella Guérin‐Méneville, is shown to be a misidentification of Platyphora selvae Daccordi.     

The structure and function of the tarsus I sensillar field in mites of the genus Halarachne (Halarachnidae: Gamasida)

The sensillar field on tarsus I of Halarachne (Halarachnidae: Gamasida), a respiratory tract endoparasite of seals (Pinnipedia) is associated with 12 hair- or peg-like receptor sensilla in the larva and 13 or 14 in the adult. These include thermo-hygroreceptors, each with a double wall traversed by 3 or 4 slit-like pores (dw/WP-sensilla), olfactory chemoreceptors of small inorganic molecules, each with a single wall spanned by several small and simple pores (sw/WP-sensilla), gustatory chemoreceptors with a single terminal pore (TP-sensilla), and aporous NP-sensilla which have thermoreceptive and/or other unknown functions. Some sensilla are sessile and others socketed, the latter having a possible additional/alternative mechanoreceptive function. One mechanoreceptor is a probable trichobothrium-like vibration receptor which has not been previously described in the Anactinotrichida. This range of sensilla combined with the absence of sw/WP-sensilla, i.e. olfactory chemoreceptors covered with numerous, large centrally-plugged pores, suggests that although Halarachne spp. can locate large endothermic animals, they lack the ability to discriminate between different species.     

A review of deviant phenotypes in bees in relation to brood parasitism,and a gynandromorph of Megalopta genalis (Hymenoptera: Halictidae)

We review the occurrence of gynandromorphy in 64 species of bee, and describe the abnormal traits as deviations from the male or female wild-type. Pheno-deviants occur at approximately equal frequency among the main body regions (head, thorax, metasoma). Cross-sex expression of character states occur more often among females (i.e. deviant expression of male-like traits) than among males (i.e. deviant expression of female-like traits). Such pathologies demonstrate how developmental switch mechanisms might generate novel structural traits similar to those expressed as a syndrome of brood parasitic traits. We also describe the first known gynandromorphic bee in the tribe Augochlorini, a specimen of the nocturnal bee, Megalopta genalis.     

Diplecogaster tonstricula,a new species of cleaning clingfish (Teleostei: Gobiesocidae) from the Canary Islands and Senegal,eastern Atlantic Ocean,with a review of the Diplecogaster-ctenocrypta species-group

The Diplecogaster-ctenocrypta species-group is reviewed; it comprises two species. The clingfish Diplecogaster ctenocrypta from the Canary Islands is redescribed. The new species Diplecogaster tonstricula, a facultative cleaner of other teleosts, is described on the basis of eight specimens and colour photos from Senegal and the Canary Islands, eastern Atlantic Ocean. The species is small, apparently not exceeding 23 mm total length; it is characterised by having nine dorsal-fin rays, eight anal-fin rays, 24–25 pectoral-fin rays, 14–15 principal caudal-fin rays, 13–16 rakers on third gill arch, pelvic disc without lateral papillae in region A, disc region B with two rows of weak papillae, interorbital distance 4.1–4.6 in head length, distance between disc and anus 14–17% of SL, head and body with 10–13 narrow vertical brownish bars, cheek with a white ocellus surrounded by black, and with a small black spot in the middle. The new species is compared with other species of the genus; a key to the six known species of the eastern Atlantic, Mediterranean and Black Sea and South African genus Diplecogaster is presented. A checklist is provided for the species of Diplecogaster and their synonyms.