Phylogeny and classification of the Scopulini moths (Lepidoptera: Geometridae, Sterrhinae)

The phylogenetic relationships of the genera in the geometrid tribe Scopulini (Lepidoptera: Sterrhinae) were examined using 141 characters of adult morphology and ecology. The study material included 92 species, representing all previously recognized genera and covering the morphological variation and full geographical range of the tribe. The cladistic analysis resulted in 20 equally parsimonious trees and a strict consensus cladogram based on these was well resolved. A majority of the recovered synapomorphic characters have been used previously in the taxonomy of the tribe. However, many novel characters were found in the sclerotized structures of the thorax. Many previously recognized genera were found to be nonmonophyletic and based on the present revised, synapomorphy-based classification, the number of recovered genera is reduced considerably. Twenty new generic synonyms and 90 new or revived species combinations are proposed. Seven genera are considered valid, with the large genus Scopula Schrank including over 85% of all species in the tribe. The taxonomic history of the tribe is reviewed and the problems of earlier classifications are discussed. A key to the genera is presented, although an informal diagnosis is preferred. All recognized genera are illustrated and a revised world checklist of the Scopulini is presented.  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 143 , 473−530.     

Developing an empirical model of stand GPP with the LUE approach: analysis of eddy covariance data at five contrasting conifer sites in Europe

This paper develops a statistical model for daily gross primary production (GPP) in boreal and temperate coniferous forests. The model applies the light use efficiency (LUE) approach, which estimates the conversion efficiency of daily absorbed photosynthetically active radiation (APAR) into daily GPP as a product of potential LUE and modifying factors. The latter were derived from daily total APAR and daily mean temperature, vapour pressure deficit (VPD) and soil water content (SWC). Modelling data came from five European eddy covariance measurement towers over 2–8 years. The model was tested against independent data from two AmeriFlux stations. The model with the APAR, temperature and VPD modifiers worked well in almost all the site–year combinations, but the SWC modifier only improved the fit in few cases. Geographical variation was found in the modifiers and potential LUE in site-specific models. When a model was fitted to pooled data, differences between sites could be explained by potential LUE, leaf area and environmental conditions. The test against the AmeriFlux data corroborated this finding. The potential LUE varied from 1.9 to 3.1 g C MJ⁻¹, and a weak correlation was found between foliar nitrogen concentration and potential LUE. Some year-to-year variation remained which could be captured by neither the pooled nor the site-specific models.     

Assimilate transport in phloem sets conditions for leaf gas exchange

Carbon uptake and transpiration in plant leaves occurs through stomata that open and close. Stomatal action is usually considered a response to environmental driving factors. Here we show that leaf gas exchange is more strongly related to whole tree level transport of assimilates than previously thought, and that transport of assimilates is a restriction of stomatal opening comparable with hydraulic limitation. Assimilate transport in the phloem requires that osmotic pressure at phloem loading sites in leaves exceeds the drop in hydrostatic pressure that is due to transpiration. Assimilate transport thus competes with transpiration for water. Excess sugar loading, however, may block the assimilate transport because of viscosity build‐up in phloem sap. Therefore, for given conditions, there is a stomatal opening that maximizes phloem transport if we assume that sugar loading is proportional to photosynthetic rate. Here we show that such opening produces the observed behaviour of leaf gas exchange. Our approach connects stomatal regulation directly with sink activity, plant structure and soil water availability as they all influence assimilate transport. It produces similar behaviour as the optimal stomatal control approach, but does not require determination of marginal cost of water parameter.     

Systematic position of the enigmatic African cycad moths: an integrative approach to a nearly century old problem (Lepidoptera: Geometridae,Diptychini)

The systematic position and hierarchical level of the moth taxon Diptychini Janse (Lepidoptera: Geometridae), the cycad moths, has remained controversial. This is partly due to their unique morphological and biological characteristics. To study the systematics, comprehensive molecular analyses of eight genes, in total 6157 bp, were carried out. We used Bayesian inference to construct phylogenetic trees. The first analysis (46 Geometridae and 7 non‐Geometridae taxa, representing all recently recognised Geometridae subfamilies) demonstrated that the Diptychini belong to the Geometridae subfamily Ennominae. The second analysis, focused on the Ennominae (70 taxa, representing 28 of 30 recently recognised Ennominae tribes worldwide), found that the Diptychini are nested well within the Ennominae; it is monophyletic and associated with the complex of southern Hemisphere Nacophorini, refuting many of the earlier hypotheses about Diptychini relationships. The Diptychini are considered tentatively valid at the tribe level, but relationships with the Nacophorini and the Lithinini need further research. The molecular findings were evaluated from a morphological point of view, which are mostly in agreement with the molecular results. The Diptychini genera are illustrated and characterised using morphological and life‐history traits. Within the Diptychini, three genera are considered valid. Durbana Warren (described in 1904) is proposed as a junior synonym of Veniliodes Warren (described in 1894) ( n.syn. ). Monotypic Larentioides Prout is combined with the tribe Lithinini ( n.comb .). Homonymy of Diptychini Mirza (described in 1991) (Pisces: Cyprinidae, Schizothoracinae) with Diptychini Janse (described in 1933) (Lepidoptera: Geometridae, Ennominae) is noted, the former requiring a replacement name.