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.     

The biology and immature stages of Thrybius togashii Kusigemati (Hymenoptera: Ichneumonidae: Cryptinae), with a description of the male

Thrybius togashii Kusigemati is found to be an ectoparasitoid of larvae of a phytophagous eurytomid, Tetramesa sp. (Hymenoptera), growing gregariously in internodal cavities of reeds (Phragmites japonica Steud.), in Japan. The female of T. togashii oviposits into reed canes and its predaceous larva consumes almost all eurytomid larvae in an internodal cavity. This species is bivoltine. The mode of parasitism of this species is unique in some respects. First, when the female oviposits, no food resources are available in the reed. Second, the parasitoid allows part of the host larvae to grow and exploits increasing food resources. The egg, pupa and first to final instar larvae and adult male are described and figured for the first time. Colour dimorphism in both sexes and adult morphology adapted to habitat and ovipositional substrate are also discussed.     

The symbiosis between the weaver ant,Oecophylla smaragdina,and Anthene emolus,an obligate myrmecophilous lycaenid butterfly

Females of Anthene emolus use the presence of the weaver ant, Oecophylla smaragdina, as oviposition cue. Ovipositing females are not attacked by the ants. The first instar larvae are adopted by the ants and carried into their pavilions where the caterpillars feed. Outside the pavilions the larvae cannot survive. The older larvae leave the pavilions and are carried by the ants to their feeding places or back into the pavilions. The larvae are constantly attended by the ants. During the 3rd and 4th instar the caterpillars secrete high amounts of nutritive liquids representing an estimated energy content of 200 J per larva. Thus the larvae are important trophobionts of Oe. smaragdina and attract the ants by releasing food recruitment behaviour. The pupae are not attractive for ants, but are not attacked, either. The emerging adults are not protected from ant attacks and are sometimes killed by their host ants. The costs and benefits of this close obligate myrmecophilous relationship for both the ants and lycaenids as well as the evolution of ant-specific relationships of the lycaenids are discussed.     

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.     

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.     

A remarkable,new Australian sawfly with brachypterous,nocturnal or crepuscular females (Hymenoptera: Symphyta: Pergidae)

A new species of sawfly, Clarissa tasbates, is described from high subalpine (860 m), grassy eucalypt woodland in western Tasmania. Females have abbreviated wings with reduced venation, are nocturnal or crepuscular, and occur on the ground or on grass tussocks. Males are macropterous and both nocturnal and diurnal. Presumed larvae are ground dwelling and feed on Ranunculus.     

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.     

Larval development and emigration behaviour during sea-to-land transition of the land hermit crab Coenobita brevimanus Dana, 1852 (Crustacea: Decapoda: Anomura: Coenobitidae) under laboratory conditions

To determine the early life history of the land hermit crab Coenobita brevimanus Dana, 1852, larvae were cultured individually in the laboratory. The zoeal and the megalopal stages are described and illustrated. The larvae developed through four planktonic zoeal stages to the megalopal stage. The major differences in the zoeal characters between C. brevimanus and other described Coenobita species were found in the armature of the pleomeres, whereas the character of pleomeres of C. brevimanus zoeae is the same as that of the coconut crab Birgus latro, a different genus in the same family. Morphological similarity was also found in segmentations of antennules and antennae in megalopae between C. brevimanus and the coconut crab. Megalopae of C. brevimanus were cultured in containers holding seawater and a hard substrate. These crabs migrate from the sea to land after developing a habit of acquiring gastropod shells.     

A new species of mycophagous Rentonium (Coleoptera: Cleroidea: Trogossitidae) based on larvae and adults,and a catalogue of Rentoniinae

Adults and associated larvae of Rentonium bicolor sp. nov. are described from New Zealand (North Island) and represent the first associated larvae of the Rentoniinae. Larvae and adults were found among the fruiting bodies of Hypocrea rufa (Pers.) Fr. (Ascomycota: Hypocreaceae). The larvae are morphologically similar to a previously described and undetermined larva but differ from it by the unpaired, hook-like urogomphus, four stemmata, and the apical antennal seta subequal in length to the antenna. Potential implications for phylogeny of Cleroidea are discussed. A catalogue of the genera and species of Rentoniinae is provided, along with comments about the status of Rentonellum loebli Kolibá?.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:936541AB-1802-4C09-9032-7EF1FAAC912E     

Discovery of a predaceous drosophilid Acletoxenus indicus Malloch in South China,with descriptions of the taxonomic,ecological and molecular characters (Diptera: Drosophilidae)

A drosophilid, Acletoxenus indicus Malloch, with larvae preying on Aleurodicus dispersus and Aleurocanthus sp. (Hemiptera: Aleyrodidae), is discovered from Guangdong and Hainan Provinces, China, and its morphological, ecological and molecular characters are described.     

Size,spines and crochets: defences of luna moth caterpillars against predation by brown anoles

Field-testing predator-prey interactions between invasive exotic brown anole lizards and sentinel larvae of the luna moth, Actias luna, suggests that late instars of this saturniid, and perhaps many other saturniids, are well defended by their spines and crochets against predation by lizards. However, Actias luna larvae remain vulnerable to anole predation until they reach about 3 cm in length. In contrast, even relatively small caterpillars that are chemically defended, such as those of the io moth, Automeris io, and the monarch butterfly, Danaus plexippus, were shown to be well defended against anoles by their toxins. There is an obvious advantage for caterpillars to be chemically defended. However, there is also a tradeoff: Danaus plexippus are restricted to feeding on a relatively small group of plants, which limits resources and requires specialisation; in polyphagous Automeris io, the constant production of elaborate spines and toxin leads to prolonged larval development, which is at least twice as long as that of Actias luna, and exposes the caterpillars to mortality factors such as parasitism for a longer duration.