Merrill H. Sweet

Parastrachiinae (Hemiptera: Cydnidae) Raised to Family Level

Abstract Parastrachia, with its two species P. japonensis (Scott) and P. nagaensis Distant, has been placed as a subfamily (Parastrachiinae) in Cydnidae. Those who placed it there [C. W. Schaefer, Dolling, W. R., and S. Tachikawa. 1988, The shieldbug genus Parastrachia and its position within the Pentatomoidea (Insecta: Hemiptera). Zool. J. Linn. Soc. 93: 283–311] expressed their doubts at the time. We confirm those doubts after comparing Parastrachia with several pentatomoid groups, including Pentatomidae and Cydnidae. We conclude that the genus warrants family-level rank, as Parastrachiidae Oshanin, 1922.

Do Chaoborus larvae migrate in temporary pools

A diurnal vertical migration of larvae of Chaoborus punctipennis (Say) was observed in shallow temporary woodland pools in East Texas. In the laboratory, in 153 cm tall columns, the larvae underwent a much greater migration than possible in the shallow pools. We hypothesize that the migratory behavior and transparent body of Chaoborus larvae may have originally evolved in such shallow water habitats. These traits enabled Chaoborus to successfully invade the quite different adaptive zone of predation in the plankton of deep lakes.

The genus Plinthisus Stephens in the Australian Region (Hemiptera: Lygaeidae)

Fifteen species of Plinthisus are reported from Australia, all of them previously undescribed. The new species are: P. woodwardi, P. australiensis, P. tasmaniensis, P. kangarooensis, P. acrocephalus, P. nudus, P. sericeus, P. platycephalus, P. mullewa, P. dampieris, P. reticulatus, P. tindalis, P. flindersi, P. bassianus and P. grossi. P. woodwardi is also reported from New Zealand. The species are segregated into five groups. Their distributions within Australia and relationships to Oriental, African and South American taxa are discussed. A key to species is included. Plinthisus tineoides (Distant), an Oriental species, is redescribed and Locutius atratus Distant, 1918 and Locutius pallescens Distant, 1918 placed as junior synonyms. The ecological habitats and host plant relationships of P. australiensis, P. nudus, P. bassianus and P. grossi are discussed. Descriptions of nymphs are given for P. woodwardi, P. australiensis and P. grossi. Sixty figures are included illustrating dorsal views, spermatheca, metathoracic scent gland areas, eggs, wings, aedeagus, sperm reservoirs, parameres and abdominal details.

Enzyme variability in an intertidal anomuran, Clibanarius vittatus

Abstract Six enzyme loci ( Ldh -1, G6pdh , Mdh -1, Mdh -2, Xdh , and To ) within two populations of Clibanarius vittatus , the striped hermit crab, were analysed. Thirty-three percent of the Ioci were polymorphic and the average heterozygosity was 0.146. Genetic identity between the populations was 0.902.