Equine Culicoides hypersensitivity in Florida: biting midges aspirated from horses

Nine species of Culicoides were aspirated from horses in Florida during the second phase of a study of equine Culicoides hypersensitivity (CHS). Approximately 90% of the 2933 midges were Culicoides insignis Lutz, 4% were C.stellifer (Coquillett), 3% were C.niger Root and Hoffman, 2% were C.alachua Jamnback and Wirth and the remaining 1% included C.venustus Hoffman, C.scanloni Wirth and Hubert, C.lahillei Iches (= C.debilipalpis Lutz), C.pusillus Lutz, and C.edeni Wirth and Blanton. Culicoides were sampled on seven farms located throughout Florida. The location and seasonality of lesion development on horses with CHS correlated with the Culicoides spp. collected directly from the horses as to their sites of attack, their seasonality and geographical distribution.     

Efficacy of the Entomopathogenic Fungus, Culicinomyces clavisporus against Larvae of the Biting Midge, Culicoides nubeculosus (Diptera: Ceratopogonidae)

Culicinomyces clavisporus, a fungal pathogen of a wide range of mosquito species, was investigated in relation to potential pathogenicity against Culicoides nubeculosus biting midge larvae. Seven different C. clavisporus strains were assayed. Each showed some degree of activity against C. nubeculosus larvae with LC₅₀ values of between 3.2×10^-5 and 1.1×10^-6 spores/mL; these effects occurred in dose-dependent manners and tended to be delayed until 72-96 h post treatment. The results are discussed in relation to incorporation of C. clavisporus into biocontrol programmes for Culicoides spp.     

Descriptions of a new species and the pupae of two known species of Culicoides Latreille (Diptera: Ceratopogonidae) from India

Pupa, and adult male and female of Culicoides pseudosimilis n. sp., and pupae of two known species, C. selangorensis Wirth & Hubert, and C. dryadeus Wirth & Hubert, are described and illustrated. An identification key to the Indian species of Clavipalpis and Shermani species group of male Culicoides is also provided.     

Production of the predaceous midge tribes Sphaeromiini and Palpomyiini (Diptera: Ceratopogonidae) in Lake Norman,North Carolina

Production and P/B ratios of predaceous midges of the tribes Sphaeromiini and Palpomyiini (Diptera: Ceratopogonidae) collected from sublittoral and littoral depths in Lake Norman, North Carolina, were estimated by the size-frequency method. Production estimates in g dry wt/m²/yr at eight sampling locations ranged from 0.002 to 0.022. The littoral zone as a whole was more productive (0.015 g/m²/yr) than the sublittoral zone (0.006 g/m²/yr). The P/B ratios ranged from 2.37 to 3.78 among all stations and depths.     

一种泡蟾的配偶识别:脑、行为和进化研究

综述了对泡蟾(Physalaemuspus pustulosus)的性通讯所进行的各种研究。本文作者研究了通讯系统的功能重要性、通讯的神经机制以及通讯进化的格局,特别研究了雌蛙如何使用简单和复杂的叫声来识别可以交配的物种,以及如何识别同种的不同雄性个体。本文确定了复杂叫声的反选择力、一种食蛙蝠——缨唇蝠(Trachops cirrhosus)以及叫声的能量消耗,并阐述了引起雌性反应的重要特征。作者的比较研究表明,对复杂叫声的偏好在复杂叫声进化前就有了,这支持感官开发假说(Hypothesis of sensory exploitation,雄性特征进化的结果是开发雌性预先存在的对雄性的偏好)。结合比较研究和人工神经网络的模拟,作者认为雌蛙用来识别雄性简单叫声的解码策略受其祖先解码策略的影响[动物学报49(6)：713～726,2003]。     

不同来源地同种植物种群间物候期比较研究

通过比较西双版纳植物园内雨树和甜菜豆不同大洲来源种群间的物候期,本研究探讨了两种植物种群间的物候分化现象及其与气候因子的关系。结果发现:(1)两种植物不同来源地种群间物候期相似,但是同步性不高,呈现明显的分化现象,且不同种群间萌叶起始期先后顺序差异显著;(2)不同种群间物候期同步系数与气候因子相关,尤其干季气候因子。因此可以认为:不同的生境气候因子是导致两种植物不同种群间出现物候变异的重要因子,并且这种关系可能会影响不同种群对气候变化的响应。     

Seasonal patterns of leaf production in co‐occurring trees with contrasting leaf phenology: time and quantitative divergences

Neotropical savannas (‘cerrados’) of Central Brazil are characterized by the coexistence of a large diversity of tree species with divergent phenological behaviors, which reflect a great diversity in growth strategies. In the present study time behavior and quantitative aspects of shoot growth, shoot mortality, and leaf longevity and production were analyzed in 12 woody species of contrasting leaf phenology, adopting a functional group approach where 12 species were categorized into three functional groups: evergreen, decidous and brevideciduous, according to their leaf phenology. Shoot growth and leaf production were seasonal for the three functional groups, differing in their time of occurrence, but being concentrated during the last months of the dry season. Shoot growth differed between evergreens and deciduous, as well leaf production. Evergreens had higher rates of shoot growth, produced a higher number of leaves and had longer leaf longevity (around 500 days against 300 days in deciduous and brevideciduous). Leaf longevity was associated with patterns of leaf production when accounting for all phenological groups studied. It was possible to identify different patterns of aerial growth in savanna phenological groups, providing evidence of great functional variability amongst the groups studied.     

Activity of fruit-piercing moths, Eudocima spp. (Lepidoptera: Noctuidae), in north Queensland crops: Some effects of fruit type, locality and season

Fruit-piercing moth activity was assessed in lychee or carambola crops on the wet tropical coast and on the dry tropical tablelands of north-eastern Queensland between 1985 and 1993. Monitoring occurred at fruiting, from 30 min after sundown for 1 h by systematically inspecting orchard trees under torchlight. Six species were recorded: Eudocima fullonia (Clerck), Eudocima jordani (Holland), Eudocima materna (L.), Eudocima salaminia (Cramer), Eudocima aurantia (Moore) and Eudocima cocalus (Cramer). Moths were detected between November and August, with activity lowest during the driest months (July–October) when fruit availability also decreased. Most annual variation in moth numbers occurred at the beginning of the wet season (November–December) when lychees cropped. The principal species recorded at all three sites on both fruit types between November and mid-March was E. fullonia . It represented 95.5% of the moths on coastal lychees. During autumn, the major species in carambola crops were E. jordani on the coast and E. materna on the tablelands (where total activity was only about half that in the coastal crop). Over all sampling years, 77.9% of all moths caught on coastal fruit were males, compared to 51.4% on tableland fruit. Of the female moths dissected from all sites, 77.7% contained spermatophores and fully developed eggs. An assessment of moth activity through a single night (19.00–05.00 h) in coastal carambolas showed that 72.9% of all moths arrived before midnight. The results indicate that there are opportunities in tableland areas for fruit production during the dry season without the need for control measures.