Differentiation and adaptive radiation of amphibious gobies (Gobiidae: Oxudercinae) in semi-terrestrial habitats

During several surveys made in the region of the lower Fly River and delta, Papua New Guinea, nine species of oxudercine gobies (Gobiidae: Oxudercinae) were recorded: Boleophthalmus caeruleomaculatus, Oxuderces wirzi, Periophthalmodon freycineti, Periophthalmus darwini, Periophthalmus novaeguineaensis, Periophthalmus takita, Periophthalmus weberi, Scartelaos histophorus and Zappa confluentus. An exploratory multivariate analysis of their habitat conditions discriminated five guilds, differentially distributed in habitats with different quantities of environmental water and three guilds corresponding to different levels of salinity. A partial correspondence between phylogenetic and ecological categories suggested the presence of parallel adaptive radiations within different genera. In particular, the species found in the most terrestrial habitats (P. weberi) was also found in the widest range of conditions, suggesting that colonization of extreme semi-terrestrial and freshwater habitats by this species was facilitated by eurytypy. It is proposed that these findings provide insight into convergent adaptations for the vertebrate eco-evolutionary transition from sea to land.     

Levels of genetic variability in sculpins (Gottidae: Teleostei) of the North American Pacific coast and an assessment of potential correlates

We examined levels of allozymic variation in intertidal sculpins of the genera Oligocottus, Clinocottus and Artedius. Variability in these species, as assessed by the proportion of loci polymorphic and average heterozygosity per locus, was generally low but within the range of values observed for other fish groups. In reviewing the ecological and life-history attributes of these sculpins, we found only one outstanding correlate of allozyme variability–larger-bodied species tended to have lower levels of variation. Also, the level of heterozygosity was not related in any obvious way to historical/ evolutionary aspects such as position in phylogenetic trees or the inferred relative ages of species. Our study of a relatively well-defined lineage of fishes that co-occur in the same geographical region and in the same, or broadly similar, habitats, underscores the difficulty of detecting correlations between genetic variability and seemingly relevant ecological features of species.     

Habitat segregation and cryptic adaptation of species of Periophthalmus (Gobioidei: Gobiidae)

A study was conducted on the habitat distribution of four sympatric species of Periophthalmus (the silver‐lined mudskipper Periophthalmus argentilineatus, the slender mudskipper Periophthalmus gracilis, the kalolo mudskipper Periophthalmus kalolo and the Malacca mudskipper Periophthalmus malaccensis) from northern Sulawesi. Molecular phylogenetic reconstructions based on one mtDNA marker (16S) were used to validate the morphological taxa, identifying five molecular clades. Periophthalmus argentilineatus includes two molecular species, which are named Periophthalmus argentilineatus clades F and K. Multivariate direct gradient analysis show that these species form three distinct ecological guilds, with the two molecular species occurring in different guilds. Periophthalmus clade F is ecologically eurytypic; Periophthalmus clade K and P. kalolo are prevalent in ecosystems isolated by strong oceanic currents and at shorter distances from the sea; P. gracilis plus P. malaccensis are prevalent in ecosystems connected by shallow coastal waters, in vegetated habitats at larger distances from the sea. This indicates for the first time that mudskipper species exhibit a range of adaptations to semiterrestrialism not only within genera, but even within morphospecies, delineating a much more complex adaptive scenario than previously assumed.     

厦门水域中华白海豚栖息地选择的初步研究

中华白海豚（Sousa chinensis）在中国水域主要包括3个种群,分别分布在珠江口（包括香港）、九龙江口（厦门水域）和北部湾广西沿岸水域,近年来在台湾西海岸和广东的雷州又陆续发现了新的种群（Wang et al．,2004;周开亚等,待发表资料）。该物种主要以中小种群分布于近岸浅水水域,易受各种人类活动的影响,如渔业捕捞、船舶航运、港口建设和水体污染等,其保护状况引起了人们的广泛关注。在1988年颁布的《中华人民共和国野生动物保护法》中,已将该物种列为国家一级保护动物。     

Consequences of migratory strategy on habitat selection by mule deer

Ungulate behavior is often characterized as balancing selection for forage and avoidance of predation risk. Within partially migratory ungulate populations, this balancing occurs across multiple spatial scales, potentially resulting in different exposure to costs and benefits between migrants and residents. We assessed how availability and selection of forage and risk from predators varied between summer ranges of migrant and resident mule deer (Odocoileus hemionus; a species in which individual migratory strategies are generally fixed for life) in 3 study areas in western Montana, USA, during summers 2017–2019. We hypothesized that mule deer would face a tradeoff between selecting forage and avoiding predation risk, and that migration and residency would pose contrasting availability of forage and risk at a broad (summer range) spatial scale. We hypothesized deer exposed to lower forage at a given spatial scale would compensate for reduced availability by increasing selection of forage at the cost of reduced avoidance of predators, a mechanism whereby migrants and residents could potentially achieve similar exposure to forage despite disparate availability. We compared the availability of forage (kcal/m²) and predation risk from wolves (Canis lupus) and mountain lions (Puma concolor) between summer ranges of each migratory strategy, then assessed how selection for those factors at the home range (second order) and within-home range (third order) scales varied using resource selection functions (RSFs). As forage availability increased among mule deer summer ranges and individual home ranges, selection for forage decreased at the second-order (P = 0.052) and third-order (P = 0.081) scales, respectively, but avoidance of predators varied weakly. In 1 study area, summer range of residents contained lower forage and higher risk than summer range of migrants, but residents compensated for this disadvantage through stronger selection of forage and avoidance of risk at finer spatial scales. In the other 2 study areas, summer range of migrants contained lower forage and higher risk than residents, but migrants did not compensate through stronger selection for beneficial resources. The majority of mule deer in our study system were migratory, though the benefits of migration were unclear, suggesting partial migration may persist in populations even when exposure to forage and predation risk appears unequal between strategies.     

光强度对大草蛉成虫感光性和趋光性行为的影响

运用视网膜电位（electroretinogram, ERG）技术和行为学方法研究了大草蛉Chrysopa pallens Ramber成虫的光强度反应。结果显示: （1）白光（Log I= 4.5~0.0）可引发2 h暗适应的大草蛉复眼的电位反应。随光强增强其ERG值呈近线性增大, 最强时未出现高端平台, 表明该光强范围内其感光性基本一致, 且可感受更强的光; （2）一定光强度（Log I= 4.0）以上的白光可引发大草蛉较明显的趋光性行为, 该行为具有光强域值特征和较明显的光强度依赖性。弱光时（Log I=4.5）无趋光性行为, 随光强增大趋光性反应率增大, 光较弱（Log I= 4.5~1.5）时增大缓慢, 较强（Log I=1.5~0.0）时迅速增大, 至最强（Log I=0.0）时最大（37.1%）, 呈一近“J”型式样。避光行为无或很低, 且无规律, 最大值仅为4.5%。这些结果表明: 光强度是大草蛉感光性与趋光性行为的重要决定因素, 强光时感光性电位反应与趋光性行为反应基本一致, 弱光时则不同, 暗示了光强度信息在感光性和趋光性间作用的有条件性和复杂性。     

Rediscovery of Bembidion (Lymnaeum) nigropiceum (Marsham) (= puritanum Hayward) in Massachusetts, with remarks on biology and habitat (Coleoptera, Carabidae, Bembidiini)

Bembidion (Lymnaeum) nigropiceum (Marsham) (=puritanum Hayward), a European species introduced into Massachusetts but presumed not to have become established, has been rediscovered during the Boston Harbor Islands All Taxa Biodiversity Inventory undertaken by the Museum of Comparative Zoology and the National Park Service. A summary is presented of treatment of this species in North America. Data on specimens collected are presented, along with observations on habitat and biology. Some speculations are presented about its highly specialized habitat in the gravel pushed up by high tide, which may act as a food-trapping sieve. A few words are included about future actions needed to resolve questions of distribution and behavior.     

Penetration of blue nad UV radiation measured by fiber optics in spruce and fir needles

The penetration of blue light (460 nm) and UV-A (360 nm) radiation into needles of spruce ( Picea engelmannii Parry ex. Engelm.) and fir [ Abies lasiocarpa (Hook.) Nutt. var. Iasiocrpa ] was examined. The distribution of collimated and scattered light in intact needles was measured by quartz fiber optic microprobes. Both blue light and UV-A were attenuated more rapidly with depth in fir than in spruce, although the light profiles for the two light regimes were different; blue light penetrated to a greater depth than UV-A, Removal of the epicuticular wax from the needle surface increased the amount of internal blue light slightly, but had little effect on the amount of UV-A. The differences in light penetration in light penetration in spruce and fir may be caused bhy different pigmentation and leaf anatomy.     

毛白杜鹃‘紫萼’的光适应性及最适光强的研究

从形态、生理角度研究了杭州园林中应用最广泛的杜鹃‘紫萼’(Rhododendron mucronatum cv Plenum)的光适应性和最适光强生境。结果表明:随着叶片遮荫程度的增加,杜鹃的叶面积和叶绿素含量增加;光补偿点、光饱和点及暗呼吸强度下降,说明杜鹃对弱光生境有一定的适应性。另一方面,随着相对光强的增加,叶片厚度,比叶重以及栅栏组织、海绵组织厚度及其比值,可溶性蛋白质及净光合速率增加,表现出对阳生生境更好的适应性。在生境65％全光照时,植株在形态,解剖及生理上均处于最佳状态。因此,65％全光照的生境是毛鹃‘紫萼’的最佳光生境。     

Breeding ecology and nest aggregations in a population of Salaria pavo (Pisces: Blenniidae) in an area where nest sites are very scarce

In this paper we present data on the breeding ecology and patterns of nest aggregation in a population of Salaria pavo (Pisces: Blenniidae), in an area where hard substrates are very scarce. The study site was at Ria Formosa, an extensive littoral lagoon on the south coast of Portugal. The only hard materials available are bricks, tiles, stones and debris that clam culturists use to delimit their fields. The males of S. pavo establish nests intertidally in the holes of the bricks where they guard the eggs. Data were collected at low tide inspections of these artificial ridges and underwater behavioural observations during high tide. The main results are: (i) the same male can establish sequentially more than one nest in the same breeding season; the number of males that stay within the bricks increases before the start of the breeding season and declines towards its end; (ii) there is a large excess of mature males that do not establish nests and they are significantly smaller than the nesting males, suggesting very strong competition for nest sites; (iii) the nests of several males occur in adjacent holes of the same brick, sometimes being entirely surrounded by other nests. Thus, in this population, there is virtually no defended territory around the nest, a situation not known for other blenniid species. This pattern of nest aggregation implies both strong competition among males and reduction of aggression between neighbour parental fishes. This can be explained by the extreme scarcity and spatial distribution of available nest sites.     

Sublethal effect of chlorpyriphos and fenpropathrin on functional response of Habrobracon hebetor (Hym.: Braconidae)

One of the criteria for selecting a suitable natural enemy is its functional response to different densities of the host. Habrobracon hebetor (Say) is a larval ectoparasitoid of several species of lepidopteran. Functional response of H. hebetor, after treatment with LC₂₅ of chlorpyrifos and fenpropathrin in three stages, was assessed to different densities of fifth instar of Ephestia kuehniella (2, 4, 8, 16, 32 and 64). LC₂₅ values were estimated to be 0.043, 5.36 and 2.00 and 0.38, 13.9 and 4.45?mg a.i. l^?1 for the larval, pupal and adult stages for chlorpyrifos and fenpropathrin, respectively. Host densities were offered to treated wasps for 24?h. Experiments were replicated 10 times. The results showed that the functional responses of wasps in control as well as immature stages treatments were Type III, whereas those of adult stage were Type II. a (Type II) or b (Type III) and T_h parameters were evaluated with Roger’s equation. b and T_h in control were assessed to be 0.0129 and 0.1723?h, respectively. These parameters were estimated in chlorpyrifos and fenpropathrin to be 0.0052, 0.00718 and 0.1945, 0.2492?h in larval stage; 0.00817, 0.00916 and 0.2736, 0.3108?h in pupal stage; and a and T_h were 0.0064, 0.0137?h^?1 and 0.2492, 0.2242?h in the adult stage, respectively. The insecticide had no significant effect on the searching efficiency of H. hebetor compared with those treated in control; however, they had significant effect on the handling time of the parasitoid and increased it, except in the larval stage treated with chlorpyrifos treatment.     

Associations with habitat versus geographic cohesiveness: size and shape of Bembicium vittatum Philippi (Gastropoda: Littorinidae) in the Houtman Abrolhos Islands

In the Houtman Abrolhos Islands, Western Australia, the direct-developing littorine snail Bembicium vittatum occupies a wide range of habitats, which are replicated across the three major groups of islands. Earlier studies showed that allozyme similarities followed patterns related to gene flow, independent of habitat, providing an excellent opportunity to test for associations with habitat for traits more likely to be adaptively important. As the first test for adaptive divergence, we examined variation in size and shape of shells among 131 populations in the Abrolhos Islands. Two-fold variations were found in width of adults, the allometric coefficient of height with width, and shell height scaled to a standard width. Quantification of habitat characteristics was summarized by principal components analysis. In contrast with the patterns of divergence for allozymes, shell height, adjusted for width, was strongly associated with habitat: flatter shells are found on exposed, vertical shores, while domed, more globose shells predominate in sheltered sites. This association was stronger for shape of adult-sized snails than for height scaled to an arbitrary size, highlighting the importance of using biologically relevant measures. Even highly isolated and allozymically less variable populations in tidal ponds conformed to this association. Because differences in shape are highly heritable in B. vittatum , this association of shape with habitat, independent of patterns of gene flow, indicates local adaptation. Shell size also varied with habitat, but because growth rate is highly plastic, variation in size cannot be interpreted simply in terms of adaptation. Nevertheless, the pattern of variation indicates that, within realized limits, larger size is generally favourable, but may be constrained by local conditions. Thus, variation in size signals the potential for adaptive divergence of life histories among the many, isolated populations of this species.     

Effect of light colours and weather conditions on captures of Sogatella furcifera (Horváth) and Nilaparvata lugens (Stål)

To study the phototactic responses of white‐backed planthopper, Sogatella furcifera (Horváth) and brown planthopper, Nilaparvata lugens (Stål) to different wavelengths, four colours of light traps (blue, green, yellow and red light‐emitting diodes) were placed in the same rice field along with a traditional black light trap. This study revealed that S. furcifera and N. lugens are more attracted to blue and green lights than that to yellow and red lights. During the 24 nights, compared with the black light trap, the blue LED trap could catch more rice planthoppers at 17 nights. Furthermore, catches of other species (moths and beetles) were substantially reduced in blue LED light traps. Multiple regression models were developed to assess the effect of weather factors on light trap catches of rice planthoppers. Rainfall and mean air temperature at a night mainly affected light trap catches of S. furcifera. Higher rainfall and lower temperature increased light trap catches of S. furcifera. However, wind speed was the main factor affecting the catches of N. lugens, and the lower incidence of catches was found in the night when wind speed exceeded 3.08 m/s. S. furcifera may be flying against wind at light wind nights by 0.3–1.5 m/s, whereas N. lugens may be flying down at strong wind nights by 1.5–3.08 m/s. Relative humidity did not significantly influence on trap catches. Consequently, light wavelengths, precipitation, average temperature and wind should be considered when monitoring rice planthoppers by light traps. Therefore, the blue LED light traps are worth using for monitoring planthoppers.     

Effect of habitat complexity on the predation of Buenoa fuscipennis (Heteroptera: Notonectidae) on mosquito immature stages and alternative prey

Notonectids are well‐known predators in aquatic habitats, where mosquito larvae, chironomids, and cladocerans constitute their main diet. Our purpose was to assess the effect of structural complexity on the predatory ability of Buenoa fuscipennis, a common predator in aquatic habitats of Buenos Aires city (Argentina). Buenoa fuscipennis showed type 2 functional responses in both the presence and absence of prey refuge and no differences in attack rate or handling time between refuge treatments. Regarding mosquito size classes, B. fuscipennis exhibited a significantly higher preference for 2^nd instar larvae and no predation on pupae. In the presence of mosquito larvae and alternative prey, B. fuscipennis preferred mosquitoes over chironomid larvae and adult cladocerans over mosquito larvae. No switching behavior was detected in our experiments. Habitat structure only slightly affected the predator´s consumption rates on mosquito larvae. Overall, preference for prey did not vary with the presence of refuge, except for the preference for mosquitoes over chironomid larvae, which was significantly decreased in the presence of refuge as a consequence of reduced predation on mosquito larvae. The results suggest that B. fuscipennis could efficiently control mosquitoes in structurally simple habitats where chironomids are the most abundant alternative prey but not in temporary pools where cladocerans are abundant.     

贺兰山岩羊（Pseudois nayaur）夏季取食和卧息生境选择

采用直接观察法和痕迹检验法对贺兰山岩羊夏季取食和卧息生境选择进行研究.结果表明,夏季岩羊偏好的取食地位于海拔高度1 600～2 000 m的山地疏林草原带,地形为平滑起伏的坡、明显断裂的坡和悬崖,以灰榆和山杨为优势乔木或无树,乔木矮小稀疏且距离远,接近低矮但密度较大的灌木,食物较多,位于<30°和>35°半阴半阳坡的下坡位,接近水源,人为干扰距离500～1 000 m,距裸岩2～5 m,隐蔽级25%～75%;夏季岩羊偏好的卧息地具有位于海拔高度1 600～2 000 m和>3 000 m的山地疏林草原带及亚高山灌丛和草甸带,地形为明显断裂的坡和悬崖,以灰榆和山杨为优势乔木或无树,乔木和灌木均矮小稀疏且距离较远,食物较少,位于>35°阴坡的上坡位,接近水源,人为干扰距离远,接近裸岩,隐蔽程度低.岩羊的取食和卧息生境在乔木高度和距水源距离上差异不显著(P > 0.05),而其余生态因子均有显著差异(P < 0.05).与取食生境相比,岩羊选择的卧息生境具有乔木稀疏且距离较远、灌木较少、低矮且距离较远、食物丰富度低、坡度大、远离人为干扰、接近裸岩和隐蔽程度低的特征.逐步判别分析表明,食物丰富度、灌木高度、距水源距离、隐蔽级、灌木密度、灌木距离、乔木高度和乔木距离8个生态因子可以区分取食样方与任意样方,正确判别率为85.8%;而区分卧息样方与任意样方时,距水源距离、灌木高度、距裸岩距离、人为干扰距离、食物丰富度、灌木密度和灌木距离共7个生态因子发挥作用,正确判别率为89.1%.