Bionomics,behaviour and immature stages of Pelecotoma fennica (Paykull) (Coleoptera: Rhipiphoridae)

Ptilinus fuscus (Anobiidae) was confirmed as the host species of Pelecotoma fennica (Rhipiphoridae, Pelecotominae). Females of Pelecotoma oviposit into the wood infested by the host larvae. First-instar larvae are elongate, unsclerotized, very different from the triungulinid larvae known in other rhipiphorids. They search actively for the host larvae in the wood; no phoresy is involved in the life cycle. The first-instar larvae temporarily paralyse the host larva and enter its body, overwintering (some perhaps more than once) as an endoparasite. In the spring of the year of emergence, the endoparasite engorges enormously (without moulting) and develops a special sclerotized caudal structure which is then used for perforation of the host's integument. The larva undergoes a further four ectoparasitic instars. The fifth (i.e. fourth ectoparasitic) instar differs considerably from the preceding three, and is capable of boring through the wood to prepare the emergence gallery for the adult. Pupation occurs in the wood. The rate of parasitization may locally far exceed 50%. Superparasitization by the first-instar larvae is possible, but usually only 1 larva survives to the ectoparasitic stage. Larval morphology of Pelecotoma is described and illustrated. Additional data on bionomics and larval morphology are also presented for the genus Metoecus (Rhipiphorinae). Comparing the biology and larval morphology of Pelecotoma with other Rhipiphoridae, it is assumed that ancestral rhipiphorids may have been xylophilous Tenebrionoidea with predaceous or omnivorous larvae, and that the ‘triungulinid’ larvae and phoretic habits may not belong to the groundplan of the family Rhipiphoridae. The widespread opinion considering Rhipiphoridae closely related to the family Mordellidae is questioned.     

Notes on Simulium ovazzae Grenier and Mouchet (Diptera: Simuliidae) and river crabs (Malacostraca: Potamidae) and their association

Summary

Collections of crabs in the forest zone of West Cameroon produced three species—Potamonautes africanus, P. orthostylis and P. pobeguini. The P. africanus carried populations of immature Simulium ovazzae.

Analysis of crabs collected by hand and those collected in traps indicates very little overlap in the sizes of the crabs obtained by the two techniques. This problem is discussed.

The infestation rates of S. ovazzae on P. africanus were found to be highest on medium-sized crabs. The attachment sites of the S. ovazzae on the crabs were found to vary with both the size of the crab and the size of the Simulium larva.

The size distributions of S. ovazzae larvae on small crabs were found to be different from those on medium and large crabs. The characteristic deficiency of smaller larvae on medium and large crabs reported for other crab-phoretic species was also found with S. ovazzae but the smaller crabs showed a deficiency of larger larvae. A hypothesis is put forward to explain the dearth of larger larvae on the smaller crabs and the higher infestation rate on medium crabs.

S. ovazzae are shown to arrive on their hosts as single larvae carried by the current.

Six adult S. ovazzae were reared from pupae in the laboratory. Small numbers of presumed S. ovazzae biting man in Cameroon are reported.     

Action of the saproxylic scarab larva Cetonia aurataeformis (Coleoptera: Scarabaeoidea: Cetoniidae) on woody substrates

The saproxylic beetle Cetonia aurataeformis Curti (Scarabaeoidea: Cetoniidae) is a common Iberian species, whose larvae develop in tree cavities feeding on wood and litter. The aim of this paper is to analyse how the larvae of this cetonid modify the woody substrate by feeding and what the ecological implications on their microhabitat could be. Thermal analysis and infrared spectroscopy have been used to study the changes suffered by different substrates, litter and wood of Betula alba and Quercus pyrenaica, after digestion by the larvae. Results show that larvae of C. aurataeformis are able to digest polysaccharides and lignin producing a residue richer in nutrients than the original substrate and with an organic structure that contains a fraction of lignin that is easier to decompose. The main conclusion is that the action of cetonid larvae on woody substrates could facilitate their use by other saproxylic organisms in natural ecosystems.     

Pherbina mediterranea: immature stages,biology, phenology and distribution (Diptera: Sciomyzidae)

The egg, three larval instars, and puparium of Pherbina mediterranea are described. The duration of the various immature stages indicates that this specis is univoltine and spends the winter as quiescent larvae. The biology, phenology and geographical distribution are presented. The main features of the larvae are illustrated with scanning electron micrographs. A key to the adults of genus Pherbina is given.     

Homichloda barkeri (Jacoby) (Coleoptera: Chrysomelidae: Alticinae), a candidate agent for the biocontrol of prickly acacia,Acacia nilotica (Mimosaceae) in Australia

The status of Homichloda barkeri (Jacoby) n. comb. is discussed. A key is presented to four Afrotropical Homichloda species, including fulva n. sp. The eggs, larvae and pupae of H. barkeri are described for the first time. Unusual adult and immature stage characters are discussed in relation to the placement of Homichloda in the Alticinae.     

Description of the biology and immature stages of Pagyris ulla (Hewitson) (Lepidoptera: Nymphalidae: Ithomiini) in the Colombian Andes

The biology and immature stages of Pagyris ulla (Hewitson, [1857]) (Lepidoptera: Nymphalidae: Ithomiini) are described for the first time. The species’ host plant is established to be Brugmansia candida Pers. (Solanaceae). The life cycle from eggs to adult under laboratory conditions and ambient temperature took approximately 47 days, and the larvae passed through five instars. The larvae are gregarious, feed at night, and rest during the day in nests made by joining leaves near the apex of the plant stem.     

Immature stages of the apterous fly Badisis ambulans McAlpine (Diptera: Micropezidae)

Morphology of the mature larvae and pupae of the apterous fly, Badisis ambulans McAlpine (Diptera: Micropezidae) are described and illustrated. In addition, the curious commensal habits of the larvae are described. Each spiracular plate of the mature larva is situated at the base of a small horn; similar horns have been described in other micropezid larvae. The posterior spiracles appear to be non-functional with depressions forming the vestiges of the spiracular openings. The larvae were found inside pitchers of the Albany pitcher plant, Cephalotus follicularis (Cephalotaceae) and have a commensal relationship with the plant. They feed on the decaying pitcher plant prey and leave the pitcher to pupate. It is likely that the larva obtains oxygen from the pitcher fluid. This is the first immature micropezid described from Australia.     

A report on the Eulophid (Hymenoptera : Chalcidoidea) fauna of two Scottish birch woods

Summary

The family Boganiidae (Sen Gupta &; Crowson, 1966) is here divided into three distinct families Boganiidae, Cavognathidae and Phloeostichidae which are defined and their systematic positions discussed. The chief differences of adults and larvae are given in tabulated form. The genera Taphropiestes Reitter and Rhopalobrachium Bohemann are transferred to Cavognathidae and Phloeostichidae, and they are redefined. The family Phloeostichidae includes three subfamilies, Hymaeinae (including Rhopalobrachium) Sen Gupta &; Crowson (1966), Phloeostichinae Crowson (1955) and Agapythinae nov. (Agapytho Broun). The larvae of Hydnobioides pubescens, Rhopalobrachium clavipes and Agapytho foveicollis are described with figures for the first time.     

Alipumilio (Diptera: Syrphidae) fly association with Burseraceae tree resins in the eastern Brazilian Amazon

Numerous fly (Diptera) larvae develop in plant saps or rotting exudates, but few have adapted to resin flows of trees. Among these are some primitive syrphid genera (Syrphidae), Cheilosia in the temperate region and Alipumilio in the neotropics. A recent study of resin harvest in the eastern Brazilian Amazon has revealed a potentially new species of Alipumilio that develops in resin lumps on some species of Burseraceae trees. These resin flows are primarily stimulated by larvae of a bark-boring Sternocoelus weevil (Coleoptera: Curculionidae). This fly larva's morphology, movement in the resin and unsuccessful rearing apart from fresh resin indicate it may be consuming microbial spores or sap materials coming out of tree wounds. While Sternocoelus weevils are found in resin lumps in a range of Protium and other Burseraceae species in the region, Alipumilio larvae were only found in the resin of some of these species. The study speculates that some trees do not support Alipumilio because their resin's chemical properties are inhospitable to these larvae or inhibit the micro-organisms that they feed on.     

The complete larval development of the crab Pilumnus spinifer (Brachyura: Xanthoidea: Pilumnidae) reared in the laboratory

The complete larval development of the crab Pilumnus spinifer from the western Mediterranean was obtained in the laboratory. All four zoeal stages and the megalopa are described and illustrated. The morphological characters of the larvae of Pilumnus spinifer are compared with those of other known larvae of the genus. The zoeae of P. spinifer show the rostral spine longer than the antennule (excluding aesthetascs); short lateral spines present on the carapace, and the mediolateral processes are present only in abdominal somites 2 and 3. The megalopa is similar to that of other Pilumnidae species. The morphology of the larval stages shows very similar characteristics to that of those of P. hirtellus and P. dasypodus, among the described stages of the family.     

Larval development in Phimochirus roseus (Benedict) (Decapoda: Anomura: Paguridae) reared in the laboratory

The zoeal and megalopal stages of Phimochirus roseus (Benedict, 1892) are described and illustrated from material reared under laboratory conditions. Although the vast majority of zoeae of this species pass through only four larval stages before the moult to megalopa, an occasional fifth stage has been observed. Phimochirus roseus differs in a number of morphological attributes from the only other species of Phimochirus whose larvae have been described. However, their shared features are sufficiently characteristic to confirm the distinctiveness of the genus and its general developmental homogeneity.     

Larval anisakid nematodes from four species of squid (Cephalopoda: Teuthoidea) from the central and western North Pacific Ocean

Third-stage larvae of two species of the genus Anisakis, A. simplex (Rudolphi, 1809) and A. physeteris Baylis, 1923, and those of two types of Lappetascaris sp. are described from four species of squids from the central and western North Pacific Ocean. Larvae of Lappetascaris sp. Type A were 15-33 mm long and occurred individually free in the mantle musculature of squids, whereas those of Lappetascaris sp. Type B were considerably smaller, only 3–7 mm long, and were found in capsules on the stomach wall, each capsule containing up to 50–60 larvae. It is not known whether both larval types are conspecific or belong to two different Lappetascaris species. Anisakis simplex and A. physeteris larvae were found in Onychoteuthis borealijaponica Okada and Gonatopsis borealis Sasaki, and O. borealijaponica, respectively, whereas Lappetascaris sp. Type A and Type B larvae from Thysanoteuthis rhombus Troschel, Ommastrephes bartramii (LeSueur), Onychoteuthis borealijaponica and G. borealis, and O. bartramii, respectively. The findings represent several new host records and all these parasites are reported for the first time from squids in the central North Pacific Ocean.     

A comparative study of the larval development of Monodaeus couchi (Couch), Xantho incisus Leach and Pilumnus hirtellus (Linnaeus) (Crustacea: Brachyura: Xanthidae)

Summary

Comparative accounts are given of the larval and first crab stages of three crab species belonging to the family Xanthidae: Monodaeus couchi (Couch), Xantho incisus Leach and Pilumnus hirtellus (Linnaeus). Features are discussed that distinguish the larvae of these species from those of other N.E. Atlantic brachyrhynch crabs.     

An Australian stiletto fly (Diptera: Therevidae) parasitised by a bee fly (Diptera: Bombyliidae)

Exechohypopion therephaga sp. nov. (Bombyliidae) emerged from the pupa of Parapsilocephala ambocerina sp. nov. (Therevidae) collected near Wentworth, New South Wales, Australia. The adults, pupae and mature larvae of the bombyliid and therevid are described and illustrated. Because the therevid host was collected from soil as a larva, the first instar bombyliid planidium is presumed to attach to the therevid in the larval stage. This is the second known record of a therevid being parasitised. Both known cases occurred in Australia and involved a bombyliid parasitoid.