Reproductive biology of two species of Hyalella Smith, 1874 (Crustacea: Amphipoda: Hyalellidae) from southern Brazil

Reproduction is a critical event in the life cycle of animals, and a high amount of energy is allocated to it. The aim of this study was to characterize the reproductive biology of two recently described species of Hyalella from the north-east region of state of Rio Grande do Sul in southern Brazil. The specimens were collected during 12 months from a stream source (Hyalella georginae) and from a water reservoir (H. gauchensis), in Palmeira das Missões municipality, state of Rio Grande do Sul. Upon sampling, ovigerous females and pairs in precopulatory behaviour were separated into microtubes. In the laboratory, the cephalothorax length (CL in mm) of all specimens was measured. Male size at onset of sexual maturity was larger than that of the females, in both species. There was a correlation between the size of paired males and females: larger males carried larger females, in both Hyalella species. Precopulatory pairs were found throughout the year; however, H. georginae had a higher frequency in spring, and H. gauchensis in autumn. There was a positive correlation between the CL of ovigerous females and the number of eggs/juveniles. A reduction in the number of eggs throughout the embryonic development was observed in H. georginae. The average fecundity of H. georginae was significantly higher than H. gauchensis. The differences between the reproductive biology of these species may be related to the physical and environmental conditions at which they are exposed in their habitats.     

Systematics and biology of the Rhinocolinae (Homoptera: Psylloidea)

Based on a cladistic analysis, the subfamily Rhinocolinae is redefined to comprise 13 genera and 39 species, of which two genera and eight species remain unnamed. Four new genera and 14 new species are described; one subfamily and one genus are synonymized, and two species are recombined; one lectotype is designated. The subfamily is divided into two groups, one with a Gondwanan distribution comprising four genera in Australia, New Zealand, South America and Africa, and another with Laurasian distribution in the Palaeotropics, the Western Palaerctic and North America comprising nine genera. Twenty-one species develop on host plants in the Rutales, three on Asteraceae, three on Cistaceae and one on Zygophyllaceae. The genus Pistacia (Anacardiaceae) in particular hosts six species whose biology is discussed.     

Breeding behaviour and mating success of Phyllomedusa rohdei (Anura,Hylidae) in south‐eastern Brazil

Observations on the courtship behaviour, mating behaviour and mating success of a leaf‐frog, Phyllomedusa rohdei, population were conducted in a temporary flooded site of the Atlantic Forest, south‐eastern Brazil. We did not find any influence of size and body weight on male mating success across three scales: seasonal, nightly chorus and local groups (males found within 1?m of a mated pair). In addition, no evidence was found that female Phyllomedusa rohdei exhibit overt mate choice. The formation of mated pairs in P. rohdei occurred because males moved toward the females, rather than reverse. The only variable that was significantly related to male mating success was the number of nights of participation in chorus activity. Besides calling tactics, males showed active searching behaviour. There was no evidence of size‐ and mass‐assortative mating, and a high percentage of fertilization at all size and mass ratios of males and females was observed. Clutches in this species are produced in the same manner found in others members of Phyllomedusa; a purse‐like nest is made over water by folding a leaf around the egg mass (embryos and fluid‐filled capsules). Finally, we supply a list of several studies that examined the relationship between size or mass ratios of males and females in amplexus and its influence on fertilization rate, and show that size‐assortative mating in anurans is inconsistent (present in some species but not in other).     

On the fly fauna of the central region of the Kingdom of Saudi Arabia: new country records from Riyadh Region,with a list of associated fly species and zoogeographical remarks (Insecta: Diptera)

This study presents three genera and 10 species of flies (order: Diptera) as new country records from the Kingdom of Saudi Arabia (KSA). The flies were identified from Rawdhat Khorim National Park in Riyadh Region, the central region of KSA. The newly recorded genera are Glabellula (Mythicomyiidae), Phora (Phoridae) and Ceroptera (Sphaeroceridae), and the newly recorded species are Dilophus lingens (Bibionidae), Stichopogon deserti (Asilidae), Glabellula sp. (Mythicomyiidae), Phora sp. (Phoridae), Liriomyza lutea (Agromyzidae), Ceroptera aharonii (Sphaeroceridae), Trixoscelis deemingi, Trixoscelis migueli and Trixoscelis puncticornis (Trixoscelididae), and Physiphora leucotricha (Ulidiidae). Glabellula sp. and Phora sp. have been identified only to the genus level and are listed herein only because this is the first time they have been recorded in KSA, and additional specimens are required for their accurate identification to the species level. Also, this is the first record of Trixoscelis deemingi Wo?nica and Trixoscelis migueli Wo?nica from the Palaearctic Region. Distribution, diagnoses, remarks on biology and coloured photos are given for the recorded taxa. A list of associated fly species that were previously recorded in KSA and are identified from the study area in the present study is also presented. Zoogeographically, 33% of the identified fly species showed both Afrotropical and Palaearctic affinities, while 17% were of only Palaearctic affinity, and 8% were of only Afrotropical affinity. Elements from other regions were apparently nil. The results support the idea that the central Arabian Desert, which includes the present study area, is a transitional zone between the Palaearctic and Afrotropical regions.     

生物教学中的环境教育

在生物教学中进行环境教育应从素材的挖掘、课外活动的展开。网络资源的利用、情感教育等几个方面进行 ,应遵循内容乡土化、活动、渠道多样化等几条原则。     

《细胞生物学实验》教学的几点体会

细胞生物学是生命科学中至关重要的基础学科，细胞生物学实验课的学习，能培养学生的综合实验能力，提高学科综合素质。     

体外培养大鼠肝脏枯否细胞的生物学和免疫学特征

观察在体外培养条件下，大鼠肝脏枯否细胞（KC）的生物学特征和免疫功能表达，以实验室建立的分离和培养方法，获得大鼠肝脏枯否细胞，细胞活性和纯度分别为95％和96％，结果发现KC在体外培养条件下，培养15min后开始贴附，24h后完全贴附于玻璃培养皿，能够抵抗蛋白酶的消化，存活达4周，具有强烈的吞噬作用、特异性的过氧化物酶反应阳性和能够表达特异性的ED1抗原，研究表明采用本实验室建立的大鼠肝脏KC分离和培养方法并不影响细胞的活性，在体外条件下能够维持细胞在体时的生物学和免疫学特征，完全满足实验的需要。     

加强教学管理培养合格的中学生物学教师

生物系坚持以教学为中心的指导思想,加强教学管理(1)深入社会调查、调整培养目标;(2)调整专业结构,加强学科建设;(3)调整课程体系,改革教学内容;(4)改革教学方法,培养学生兴趣;(5)监控教学过程,评估教学质量.努力为社会培养合格的中学生物学师资.     

Breeding behaviour of the Omei tree frog Rhacophorus omeimontis (Anura: Rachophoridae) in a subtropical montane region

Breeding behaviour of the Omei tree frog, Rhacophorus omeimontis, was studied during the egg-laying period (mid-April to late June) in south-west China. The operational sex ratio of the breeding population was male-biased at 3.0?±?0.8 (mean?±?SD) on a nightly basis in Pond A and 4.3?±?1.1 in Pond B. Pairs with a male clasping a female occurred in ponds first; the amplectant pairs moved to a neighbouring plant and then released foam in leaves 14–370 cm above the pond's water surface. Immediately, other males came to join the pair, forming an amplexing group of 2 to 7 males (for all 45 breeding units observed). Among the males no direct physical competition for possession of the females was observed. Females produced foam which surrounded the subsequently-laid eggs. The whole process of oviposition lasted 45–65 minutes. After ovipositing, males left the female, the female folded and lined neighbouring leaves with more foam produced to surround the eggs further. This process took 15–45 minutes. The numbers of eggs in a clutch ranged from 457 to 837 and eggs were between 2.9 and 3.4 mm in diameter; those two measures were negatively correlated with each other. Eggs hatched after 12–17 days; the larval period lasted 63–78 days. Fertilization success was positively related to the number of males participating in matings.