Life history, habits and phylogenetic relationships of Ithycerus noveboracensis (Forster), (New York weevil) (Coleoptera: Curculionoidea)

Larvae of Ithycerus are described for the first time. Ten instars are identified with the possibility of more to be found. The pupa remains unknown. Spiracular air tubes and orifices show allometric growth and this, combined with body and head capsule measurements, is used to separate instars. Female and male reproductive systems are described. Females have two ovarioles per ovary. Adult and larval stages have four cryptonephric Malphigian tubules in the digestive tract. Adult and larval nervous systems appear to be primitive in possessing long connectives between ganglia. The first instar larva of Arrhenodes minutus (Drury) is described for the first time. The first illustrations of Antliarrhinus larvae are included. Ithycerus noveboracensis (Forster) has a two year life cycle at least and possibly three. Adults do not overwinter. Three families of woody plants are associated with Ithycerus, the Betulaceae, Juglandaceae and Fagaceae, with a preference for species of Fagaceae. Adults are also occasionally found on introduced fruit trees (Rosaceae). There is no obvious courtship in Ithycerus. Oviposit!on takes place in soil; eggs are laid singly and covered with fecal matter. The larvae feed on the vascular cambium of the roots of host plants. Several grooming movements and modes new for Coleoptera were discovered in Ithycerus and include bilateral fore-mid leg rub, mid-hindleg rub (third mode), bilateral hindleg rub (third mode), simultaneous fore-midleg rub (one side), mid-hindleg rub (other side) and flagellum extend. Female A. minutus rapidly flutter the tips of their antennae against the tip of the rostrum to dislodge wood particles trapped there while drilling egg holes. Evidence is presented for the possibility of evolution of three forms of Ithycerus in pleistocene refugia. The family Ithyceridae is maintained on the basis of new characters, primarily larval. The family is viewed as the most primitive of the four apionid-like families recognized in this study, the others being Brenthidae, Antiiarrhinidae status nov. and Apionidae. The family Antiiarrhinidae is placed near Apionidae. Adult and larval ventral nervous systems are discussed in light of their possible value as phylogenetic indicators. An evolutionary sequence is postulated for the numbers and positions of sensilla on the labra of larvae

The Species of Rhimphoctona (Xylophylax) (Hymenoptera: Ichneumonidae: Campopleginae) Parasitizing Woodborers in China

Four species of Rhimphoctona (Xylophylax) collected from P. R. China are reported. Two of them are new to science: Rhimphoctona (Xylophylax) maculifemoralis Luo and Sheng, sp.nov. reared from Tetropium castaneum (Linnaeus), and Rhimphoctona (Xylophylax) immaculata Luo and Sheng, sp.nov. One is a new record for China, R. (Xylophylax) rufocoxalis (Clément 1924) reared from T. castaneum (Linnaeus). The other is R. (Xylophylax) lucida (Clément 1924) reared from Monochamus saltuarius Gebier, Tetropium gabrieli Weise and Asemus sp. A key to species known in China is provided

Tephrochronology

Tephrochronology is the use of primary, characterized tephras or cryptotephras as chronostratigraphic marker beds to connect and synchronize geological, paleoenvironmental, or archaeological sequences or events, or soils/paleosols, and, uniquely, to transfer relative or numerical ages or dates to them using stratigraphic and age information together with mineralogical and geochemical compositional data, especially from individual glass-shard analyses, obtained for the tephra/cryptotephra deposits. To function as an age-equivalent correlation and chronostratigraphic dating tool, tephrochronology may be undertaken in three steps: (i) mapping and describing tephras and determining their stratigraphic relationships, (ii) characterizing tephras or cryptotephras in the laboratory, and (iii) dating them using a wide range of geochronological methods. Tephrochronology is also an important tool in volcanology, informing studies on volcanic petrology, volcano eruption histories and hazards, and volcano-climate forcing. Although limitations and challenges remain, multidisciplinary applications of tephrochronology continue to grow markedly

Tephrochronology and its application: A review

Tephrochronology (from tephra, Gk ‘ashes’) is a unique stratigraphic method for linking, dating, and synchronizing geological, palaeoenvironmental, or archaeological sequences or events. As well as utilising the Law of Superposition, tephrochronology in practise requires tephra deposits to be characterized (or ‘fingerprinted’) using physical properties evident in the field together with those obtained from laboratory analyses. Such analyses include mineralogical examination (petrography) or geochemical analysis of glass shards or crystals using an electron microprobe or other analytical tools including laser-ablation-based mass spectrometry or the ion microprobe. The palaeoenvironmental or archaeological context in which a tephra occurs may also be useful for correlational purposes. Tephrochronology provides greatest utility when a numerical age obtained for a tephra or cryptotephra is transferrable from one site to another using stratigraphy and by comparing and matching inherent compositional features of the deposits with a high degree of likelihood. Used this way, tephrochronology is an age-equivalent dating method that provides an exceptionally precise volcanic-event stratigraphy. Such age transfers are valid because the primary tephra deposits from an eruption essentially have the same short-lived age everywhere they occur, forming isochrons very soon after the eruption (normally within a year). As well as providing isochrons for palaeoenvironmental and archaeological reconstructions, tephras through their geochemical analysis allow insight into volcanic and magmatic processes, and provide a comprehensive record of explosive volcanism and recurrence rates in the Quaternary (or earlier) that can be used to establish time-space relationships of relevance to volcanic hazard analysis. The basis and application of tephrochronology as a central stratigraphic and geochronological tool for Quaternary studies are presented and discussed in this review. Topics covered include principles of tephrochronology, defining isochrons, tephra nomenclature, mapping and correlating tephras from proximal to distal locations at metre- through to sub-millimetre-scale, cryptotephras, mineralogical and geochemical fingerprinting methods, numerical and statistical correlation techniques, and developments and applications in dating including the use of flexible depositional age-modelling techniques based on Bayesian statistics. Along with reference to wide-ranging examples and the identification of important recent advances in tephrochronology, such as the development of new geoanalytical approaches that enable individual small glass shards to be analysed near-routinely for major, trace, and rare-earth elements, potential problems such as miscorrelation, erroneous-age transfer, and tephra reworking and taphonomy (especially relating to cryptotephras) are also examined. Some of the challenges for future tephrochronological studies include refining geochemical analytical methods further, improving understanding of cryptotephra distribution and preservation patterns, improving age modelling including via new or enhanced radiometric or incremental techniques and Bayesian-derived models, evaluating and quantifying uncertainty in tephrochronology to a greater degree than at present, constructing comprehensive regional databases, and integrating tephrochronology with spatially referenced environmental and archaeometric data into 3-D reconstructions using GIS and geostatistics

Retention of Students in Online Courses – A Presentation to Faculty

Retention of online students is an important issue for distance educators. Recently, a team from Noel-Levitz made a presentation to faculty that discusses student retention