Spinotoma ruicheni: A new Late Cretaceous genus and species of wedge-shaped beetle from Burmese amber (Coleoptera,Ripiphoridae, Pelecotominae)

A new genus and species of ripiphorid beetle is described based on a female specimen preserved in Upper Cretaceous (Cenomanian, ca. 99 Ma) amber from northern Myanmar, under the name of Spinotoma ruicheni gen. et sp. nov. It belongs to the extant Pelecotominae and represents the second documented occurrence of this subfamily in the Late Cretaceous. This new taxon is morphologically distinguishable in Pelecotominae by the combination of following characters: eyes oval, without incision; antennomeres V–X serrate, with XI fusiform; maxillary palpi unmodified; protarsi shorter than protibiae; tibiae sparsely provided with spines; tibial spurs formula 2-0-2. Together with other previously reported fossil ripiphorids, it highlights the species diversification of wedge-shaped beetles during their early evolution. On the other hand, a morphological similarity between Spinotoma and modern pelecotomines and the occurrence of xylophagous beetles in the Burmese amber suggest a similar host preference in wood-boring beetles for this species, shedding lights on an ancient host-parasitoid relationship in the late Mesozoic. This paper also provides a brief discussion on the taxonomy and evolution of Mesozoic wedge-shaped beetles. The wedged-shaped body form and fully-developed elytra in Recent Pelecotominae and Ptilophorinae are considered to be derived from their early ancestors rather than evolved with the onset of flowering plants during the Cretaceous as commonly thought.     

The Early Cretaceous evidence of rapid evolution of the genus Helius Lepeletier and Serville, 1828 (Limoniidae,Diptera)

Helius ewa sp. nov., one of the oldest representative of the genus Helius Lepeletier and Serville 1828 (Diptera: Limoniidae) from the Lebanese amber (Lower Cretaceous) is characterized, illustrated and described. The evidences of rapid evolution of the genus Helius are provided. The hypothesis on the origin of the evolution of this genus in Gondwana and the possibility of rapid radiation and expansion in Laurasia are discussed. A complete list of Cretaceous limoniids belonging to Helius is given.     

一种琥珀塑料混合体的鉴别

目前,在检测琥珀样品的过程中,我们发现了一种琥珀与塑料混合在一起的样品,与波罗的海琥珀尤其是蜜蜡非常相像.送检的琥珀塑料混合体样品主要为抛光或者亚光的圆珠散珠或圆珠手串,颜色为黄色或黄白交加,透明至不透明,树脂光泽.本文采用常规宝石学测试手段、红外光谱、拉曼光谱等方法对其进行了研究.结果表明,该样品为琥珀与塑料的熔合体,其中黄色部分为波罗的海琥珀,白色部分为醇酸树脂.该琥珀塑料混合体的鉴别特征如下:黄色、白色部分有些界限截然,有些界限不明;黄色部分常见特征的回旋纹,高倍镜下观察常见密集的微小气泡群,折射率为1.54,紫外灯下具有黄绿色的荧光,红外光谱具有2 927、1 737、1 451、1 380、1 257、1 159、983 cm^-1吸收峰,拉曼光谱具有1 655、1 453 cm^-1拉曼峰;白色塑料部分生硬呆板,放大观察常见大个气泡散布,折射率为1.60,紫外灯下具有蓝色的荧光,红外光谱具有3 061、1 728、1 600、1 580、1 493、1 453、1 282、1 123、1 067、745、701 cm^-1吸收峰,拉曼光谱具有1 735、1 607、1 460、1 048、1 011 cm^-1拉曼峰.     

Cockroach as the Earliest Eusocial Animal

<正>A completely preserved cockroach Sociala perlucida gen.et sp.nov.(Blattida:Socialidae fam.nov.)is described from the Mesozoic(Albian Early Cretaceous)amber of Archingeay in France.It is categorized within the new family Socialidae,originating from the Mesozoic cockroach family Liberiblattinidae,and representing the sister group to the most basal known eutermite families.Numerous direct and indirect morphological evidence(such as a unique narrow body and pronotum with reduced coloration,legs without carination and with numerous sensillar pitts(forelegs)as adaptations to life in nests analogical to the living termitophillous species; enlarged head,long palps for communication,a general venation modified in a direction towards termites (subcosta and radial vein[R]approximated,R branches approximated,simplified,cross-veins reduced),and possibly also the development of the breaking forewing sutura for detaching wings after marriage flight),suggest its eusocial mode of life.Thus,the first eusociality originated within cockroaches,prior to giving birth to termites; termites and Cryptocercus are not directly related.The group of eusocial cockroaches makes termite morphotaxon polyphyletic,but also in this case,the erection of a new order for mastotermites(including Cratomastotermitidae)and/or the inclusion of eusocial,morphological cockroaches within termites appears counterproductive,thus an example of such a general exception to the taxonomical procedure is provided.     

琥珀与柯巴树脂的有机成分及其谱学特征综述

琥珀与柯巴树脂都属于天然树脂,两者的物化性质有一定的相似性与过渡性,但成熟度的不同导致两者存在一定的差别。在综合国内外研究文献的基础上,分析了琥珀与柯巴树脂的形成过程,对比了两者在基本性质、FTIR,Raman,^13CNMR以及热分析等谱学特征方面的异同,发现由于柯巴树脂的成熟度低、lab—danoid型二萜化合物单体组分的质量分数高,造成其谱学特征与琥珀的略有不同。最后指出,要区分琥珀与柯巴树脂应以成熟度为判别依据,并综合分析两者的物化特性与谱学特征,才能得到较科学的结论。     

用树木年轮重建博尔塔拉河流域的降水量序列

根据采自天山北坡西段博尔塔拉河流域18个采点的树木年轮样本,建立了每个采点的3种年表。通过相关普查分析,发现年表序列与上年10月至当年7月降水相关显著。用查干哈尔尕(t+1)、依和浑迪(t、t+1)、哈夏(t+2)4个树轮标准化年表序列可较好地重建该流域392a的该时段的降水量。分析重建结果发现:在这392a中,具有较明显的5个干期和6个湿期:有2a、3a、4a、12a、29a和43a的变化准周期:在1730,1753,1778和1831年发生突变。