THE GENETICS OF AN ISOLATING MECHANISM BETWEEN TWO SIBLING SPECIES OF DROSOPHILA

Matings between Drosophila simulans females and males of the sibling species D. mauritiana are of abnormally short duration. These rapid matings interrupt the transfer of sperm, leading to substantial reproductive isolation in interspecific as compared to intraspecific copulations. Genetic analysis of this behavior shows that it is influenced much more by the male than the female genotype, with genes from D. simulans being dominant. In males, shortened copulation is caused by interspecific divergence at a minimum of three loci, with one gene on each of the major chromosomes. This is an underestimate of the true number of loci affecting the trait, which could be much larger. The two autosomes have the largest effect, whereas that of the X chromosome is much smaller. The genetic architecture of copulation duration and the larger effect of male than female genotype suggest that females can detect and discriminate against differences in male genitalia.     

Pollinator shifts between Ophrys sphegodes populations: might adaptation to different pollinators drive population divergence?

Local adaptation to different pollinators is considered one of the possible initial stages of ecological speciation as reproductive isolation is a by‐product of the divergence in pollination systems. However, pollinator‐mediated divergent selection will not necessarily result in complete reproductive isolation, because incipient speciation is often overcome by gene flow. We investigated the potential of pollinator shift in the sexually deceptive orchids Ophrys sphegodes and Ophrys exaltata and compared the levels of floral isolation vs. genetic distance among populations with contrasting predominant pollinators. We analysed floral hydrocarbons as a proxy for floral divergence between populations. Floral adoption of pollinators and their fidelity was tested using pollinator choice experiments. Interpopulation gene flow and population differentiation levels were estimated using AFLP markers. The Tyrrhenian O. sphegodes population preferentially attracted the pollinator bee Andrena bimaculata, whereas the Adriatic O. sphegodes population exclusively attracted A. nigroaenea. Significant differences in scent component proportions were identified in O. sphegodes populations that attracted different preferred pollinators. High interpopulation gene flow was detected, but populations were genetically structured at species level. The high interpopulation gene flow levels independent of preferred pollinators suggest that local adaptation to different pollinators has not (yet) generated detectable genome‐wide separation. Alternatively, despite extensive gene flow, few genes underlying floral isolation remain differentiated as a consequence of divergent selection. Different pollination ecotypes in O. sphegodes might represent a local selective response imposed by temporal variation in a geographical mosaic of pollinators as a consequence of the frequent disturbance regimes typical of Ophrys habitats.     

INCIPIENT REPRODUCTIVE ISOLATION BETWEEN TWO SYMPATRIC MORPHS OF THE INTERTIDAL SNAIL LITTORINA SAXATILIS

The study of speciation in recent populations is essentially a study of the evolution of reproductive isolation mechanisms between sub-groups of a species. Prezygotic isolation can be of central importance to models of speciation, either being a consequence of reinforcement of assortative mating in hybrid zones, or a pleiotropic effect of morphological or behavioral adaptation to different environments. To suggest speciation by reinforcement between incipient species one must at least know that gene flow occurs, or have recently occurred, and that assortative mating has been established in the hybrid zone. In Galician populations of the marine snail Littorina saxatilis, two main morphs appear on the same shores, one on the upper-shore barnacle belt and the other in the lower-shore mussel belt. The two morphs overlap in distribution in the midshore where hybrids are found together with pure forms. Allozyme variation indicates that the two parental morphs share a common gene pool, although within shores, gene flow between morphs is less than gene flow within morphs. In this study, we observed mating behavior in the field, and we found that mating was not random in midshore sites, with a deficiency of heterotypic pairs. Habitat selection, assortative mating, and possibly sexual selection among females contributed to the partial reproductive isolation between the pure morphs. Sizes of mates were often positively correlated, in particular, in the upper shore, indicating size-assortative mating too. However, this seemed to be a consequence of nonrandom microdistributions of snails of different sizes. Because we also argue that the hybrid zone is of primary rather than secondary origin, this seems to be an example of sympatric reproductive isolation, either established by means of reinforcement or as a by-product to divergent selection acting on other characters.     

台湾海峡水螅水母纲—新属二新种记述

记述台湾海峡生物综合调查区水螅水母纲1新属2新种,即花水母亚纲面具水母科台湾似内胞水母Paraeuphysilla taiwanensis Xu,Huang et Guo,gen.nov.et sp.nov.与软水母亚纲多管水母科平枝多管水母Zygocanna planatus Xu,Huang et Wang,sp.nov..此外,还报道了1种黑圆口水母Stomotoca atra L.Agassiz,1862在我国海域首次记录.模式标本保存在国家海洋局第三海洋研究所.     

中国卷蛾寄蝇族一新种及二新纪录种(双翅目,寄蝇科)

长腹寄蝇属是双翅目寄蝇科卷蛾寄蝇族中的1个小属,已知2种:Dolichocoxys femoralis Townsend分布于缅甸、印度尼西亚,D.rossica Mesnil分布俄罗斯远东地区。王氏长腹寄蝇Dolichocoxys wangiZhang et Liu,sp.nov.(图1 ~7)主要特征体长12.0 ~13.0mm;触角芒具绒毛; 2后背中鬃较宽分离,小盾端鬃毛状,前胸侧板具鬃;足黑且长;雄性腹部长筒形,第5背板端部延长成细长尾。正模♂,西藏墨脱阿尼桥, 1 300m, 2003-08-10 ,王明福采;副模1 ♂,同正模; 1 ♂,西藏亚东, 1977-06-13 ,吴健毅采, 2 ♂♂,云南德钦虎跳峡, 2 800 ~2 900m, 1996年8月24 ~26日。新种近似于D.femoralis,但体型较大,足基节和腿节黑色,与后者区别明显;又与D.rossica近似,但体型较大,触角、下颚须和足均黑色,区别于后者。新种模式标本分别保存在沈阳师范大学昆虫标本馆和中科院上海昆虫博物馆。此外,报道卷蛾寄蝇族2中国新纪录种:等鬃毛颜寄蝇Admontia podomyia Brauer et Bergenstamm,1889 (四川、青海) ;黄奥斯渥寄蝇Oswaldia gilva Shi ma,1991 (辽宁)。     

新疆爱丽缨小蜂属两新种及一新纪录种记述(膜翅目,缨小蜂科)(英文)

记述采自新疆的爱丽缨小蜂属ErythmelusEnock2新种,温泉爱丽缨小蜂Erythmelus(Erythmelus)wenquanensis sp.nov.,短索爱丽缨小蜂Erythmelus(Erythmelus)brevifuniculatus sp.nov.,中国1新纪录种,盲蝽爱丽缨小蜂Erythmelus(Erythmelus)lygivorus Viggianiet Jesu,提供了新疆爱丽缨小蜂属5个种的检索表。模式标本保存在新疆大学生命科学与技术学院昆虫研究室和福建农林大学生物防治研究所。温泉爱丽缨小蜂,新种Erythmelus(Erythmelus)wenquanensis sp.nov.(图1~4)正模♀,新疆温泉县,2001-07-16,胡红英采。副模:2♀♀,来源同正模;1♀,和硕县,2001-08-07,胡红英采;5♀♀,和静县,2001-08-09,胡红英采;2♀♀,托里县,2007-07-29,张铁钢采;1♀,塔城,2007-07-30,张晶晶采;1♀,托里县,2007-07-29,何茜采;1♂,和丰县,2007-08-01,徐建华采。分布:新疆(和硕县、和静县、塔城、和丰县、托里县、温泉县)。新种外部形态特征与E.goochiEnock很相似,主要区别是:新种的第6索节略短于第4、5索节之和;棒节短于柄节至第4索节长度之和;前翅缘毛明显长于翅宽。词源:新种以模式产地命名。短索爱丽缨小蜂,新种Erythmelus(Erythmelus)brevifuniculatussp.nov.(图5~8)正模♀,新疆精河县,2001-07-15,胡红英采。副模:1♀,1♂,来源同正模;6♀♀,4♂♂,乌鲁木齐市,2001-08-22,胡红英采;1♀,新源县,1997-08-07,马德英采;2♀♀,2♂♂,新源县,2001-07-16,胡红英采;1♀,奎屯市,2001-07-17,胡红英采;2♀♀,石河子市,2001-07-12,胡红英采;2♀♀,乌鲁木齐市郊,2001-07-22,孙涛采;1♀,和硕县,2001-08-07,胡红英采;1♀,阿克苏市,2001-06-18,吴卫采;2♀♀,托里县,2007-07-29,徐建华采;1♀,额敏县,2007-07-29,张铁钢采;1♀,额敏县,2007-07-30,何茜采。分布:新疆(阿克苏市、和硕县、乌鲁木齐市、石河子市、奎屯市、精河县、托里县、额敏县、温泉县、新源县)。新种与本属中的任何种都有明显的差异,与另1新种温泉爱丽缨小蜂Erythmelus(Erythmelus)wenquanensis sp.nov.较相似,区别之处:中胸盾片端部淡黄褐色;第4索节等长于第6索节的一半;前翅缘毛长于翅宽的2倍;前翅的长宽比值大于5;雄性外生殖器的长度等长于后足胫节。词源:新种种名brevifuniculatus为组合词,由拉丁词brevi-(意为"短的")和funiculus(意为"索节")组成,指新种索节粗短。盲蝽爱丽缨小蜂Erythmelus(Erythmelus)lygivorus VigganisetJesu中国新纪录(图9~11)研究标本:1♀,新疆托里县,2007-07-29,张铁钢采;1♀,额敏县,2007-07-29,徐建华采。分布:新疆(托里县、额敏县);法国,匈牙利,意大利,西班牙。     

新疆斑翅蝗科一新属及二新种记述(直翅目,蝗总科)

记述采自新疆斑翅蝗科昆虫1新属2新种,即拟长距蝗属Longipternisoides gen.nov.、平缘拟长距蝗Longipternisoides glabimarginis sp.nov.及拟黑翅痂蝗Bryodema nigropteroides sp.nov..模式标本保存于陕西师范大学动物研究所昆虫标本室.     

中国蜉蝣属两异名及一新种记述(蜉蝣目,蜉蝣科)

我国大陆蜉蝣科蜉蝣属Ephemera中的张家界蜉E．zhangjiajiensis Zhang,Gui et You,1995实际是绢蜉E．serica Eaton。1871的同物异名(新异名),湖南蜉E．hunanensis Zhang,Gui et You,1995是梧州蜉E．wuchowensis Hsu,1938的异名(新异名)。本文还报道1新种——红斑蜉Ephemera rufomaculata sp．nov．的成熟稚虫和成虫。本种成虫腹部为棕红色,腹部背板1～2节具大面积的色块,腹部3～9节背板各具3对黑色纵纹,雄性外生殖器具发达的阳端突以及阳茎端部明显向后突出而十分独特,极易与已知种区分。本种稚虫因具有与成虫相似的腹部背板斑纹以及较小的上颚突起也易识别。     

中国异蚤蝇属二新种及一新纪录种记述(双翅目,蚤蝇科)(英文)

记述采自江西和海南省的异蚤蝇属2新种,1中国新纪录种:胫距异蚤蝇Megaselia tibisetalis Fang,sp.nov.,叉刺异蚤蝇M.setifurcana Liu,sp.nov.和阔唇异蚤蝇M.labialis Brues.模式标本存放于沈阳大学生物与环境工程学院.     

拟厉螨属二新种和中国一新纪录(蜱螨亚纲:厉螨科)

本文记述拟厉螨属二新种:中华拟厉螨 Laelaspis sinensis sp. nov.,中卫拟厉螨 Laelaspiszhongweiensis sp.nov.和中国一新纪录:骑拟厉螨L.equitans(Michael,1891)。模式标本采自宁夏海原、中卫二县,保存于宁夏回族自治区地方病防治所和南京大学医学院。     

中国五节根蚜亚科二新属五新种及一新亚种记述(同翅目:瘿绵蚜科)(英文)

作者系统整理了中国五节根蚜亚科Fordinae标本,发现2新属：离倍蚜属DimelaphisZhang,gen．nov．和拟孕蚜属SicifordaZhng,gen．nov．;5新种：榆钱毛根蚜ChaetogeolcaulmidrupaZhang,sp．nov,钝镰离倍蚜D．obtusifalcataZhang,sp．nov,金黄五节根蚜FordaauralentaZhngetQiao,sp．nov,毛多五节很蚜F.multicomaZhng,sp．nov．及六节拟孕蚜S．sexiarticulataZhang,sp．nov．二新亚种：麦拟根蚜沾化亚种ParacletuscimicformiszhanhuanusZhng,ssp.nov。模式标本保存在中国科学院动物研究所。     

闽南-粤东近海上升流区花水母亚纲一新属二新种记述(丝螅水母目,原帽水母科;头螅水母目,棒状水母科)

记述了闽南-粤东近海上升流区花水母亚纲原帽水母科Protiaridae Haeckel,1879裸球拟海帽水母1新种Halitiarella nudibulbus Xu,Huang et Guo,sp.nov.与棒状水母科Corymorphidae Allman,1872张氏八辐端粗水母1新属1新种Octovannuccia zhangjinbiaoi Xu,Huang et Lin,gen.nov.,sp.nov.。模式标本保存在国家海洋局第三海洋研究所。裸球拟海帽水母,新种Halitiarella nudibulbus Xu,Huang et Guo,sp.nov.(图1～2)鉴别特征水母伞无顶突,外伞有分散刺胞;伞缘有4条主辐位触手和4个间辐位缘基球,所有触手和缘基球有背轴眼点;主辐位触手与间辐位缘基球间具2～3条短的实心缘丝。正模(TS045)和副模(TS046-049),闽南-粤东上升流区A25站(22.8°N,118.1°E),水深32m,2009-06-11,项鹏采(第三海洋研究所)。词源:新种以拉丁词nudibulbus为种名,意为裸球,指该种间辐位缘基球无触手。八辐端粗水母,新属Octova...     

NOTES ON THE GENUS PHILOPTILA MEYRICK AND DESCRIPTIONS OF TWO NEW SPECIES (LEPIDOPTERA; LECITHOCERIDAE)

Abstract  In this paper, 2 new species, Philoptila dolichina and Ph. minutispina are described. The female genitalia are illustrated. Key is provided for all the known 5 species in the world, among them 4 species are only recorded in China and 1 in India.     

BIOCHEMICAL, PHYSIOLOGICAL, AND MOLECULAR ANALYSIS OF SEXUAL ISOLATION IN THE SPECIES COMPLEX CLOSTERIUM PERACEROSUM-STRIGOSUM-LITTORALE (CHLOROPHYTA)1

Closterium strains obtained from Japan ( NIES-64 and -65 ) and Nepal ( NIES-67 and -68 ) have been classified as the same taxonomic species; however, they are sexually isolated from each other. When NIES-64 and -65 cells were separately incubated in a medium in which both strains had previously been cultured together, release of protoplasts from both strains was observed. We suggest that factors responsible for the release of protoplasts from cells of both NIES-64 and -65 are produced in a mixed culture of these cells and function during conjugation. These factors, however, had no effect on the release of protoplasts from cells of strains NIFS-67 or -68. Alternatively, a protein that is responsible for the release of protoplasts from cells of NIES-68, called the protoplast-release-inducing protein ( PR-IP ), had no effect on the release of protoplasts from cells of strains NIES-64 or -65. When the media obtained from the culture of NIES-64 and -65 cells at various mixing ratios were analyzed by western blotting with antiserum to a 42-kDa subunit of PR-IP, no cross reaction was detected. In Southern hybridization analysis, no hybridizing band was observed when genomic DNAs of NIES-64 and -65 cells were probed with cDNAs encoding the two subunits of PR-IP. We suggest from these results that the factors responsible for the release of protoplasts from NIES-64 and -65 cells are not structurally similar to PR-IP. It is known that the release of PR-IP from NIES-67 cells can be induced by the action of another sex pheromone ( PR-IP inducer ) which is released by NIES-68 cells. In contrast, no protoplast-release-inducing activity was observed from either NIES-64 or -65 in a culture medium conditioned by opposite strains. We suggest that the conjugation systems employed by strains NIES-64/ NIES-65 and strains NIES-67 /NIES-68 differ, and we propose a possible mechanism of sexual isolation between these biological species .     

中国缓步动物门二新种及三新纪录种和亚种(异缓步纲,棘影熊虫科;真缓步纲,小斑熊虫科,大生熊虫科,高生熊虫科)

记述采自河南省洛阳市、湖北省京山县和四川省都江堰市的缓步动物门2新种及3新纪录种和亚种：异缓步纲棘影熊虫科的四棘棘影熊虫,新纪录Echiniscus quadrispinosus Richters,1902;真缓步纲小斑熊虫科的都江小斑熊虫,新种Milnesium dujiangensis sp.nov,大生熊虫科的节值大生熊虫戴冠亚种,新纪录Macrobiotus harmsworthi coronatus Barros,1942;高生熊虫科的大指等高熊虫,新纪录Isohypsibius macrodactylus(Maucci,1978)和京山等高熊虫,新种Isohysibius jingshanessis sp.nov.