Leaf-cutting ant nests in temperate environments: mounds,mound damages and nest mortality rate in Acromyrmex lobicornis

The mounds of ant nests have been characterized as structures that facilitate the colonization of habitats subject to extreme temperatures. My objective was to investigate the importance of the mound of Acromyrmex lobicornis (Formicidae, Attini) in this process. In the most climatically rigorous environment that this ant genus lives (northwestern Patagonia), I determined (1) the temperature range within Acromyrmex lobicornis nest-mounds, (2) the influence of mound damages on the mortality or abandonment rate of Acromyrmex lobicornis nests, and (3) compared, from the existing literature, the distribution limits between the species of Acromyrmex that do and do not construct mounds. The mounds of A. lobicornis function as 'thermal buffers' by diminishing the effects of external thermal variations, and previous mound damage increased mortality or abandonment only of colonies with nest mounds constructed on bare ground. Mounds constructed on tussock plants increased their diameter faster and recovered better from perturbations. This may be due to the structural support of plant stems facilitating repair. At a larger scale, the species of Acromyrmex with mounds have more southerly range limits than species that do not construct mounds, indicating an important function of this nest structure for the colonization of temperate environments.     

Extreme convergence in stick insect evolution: phylogenetic placement of the Lord Howe Island tree lobster

The ‘tree lobsters’ are an enigmatic group of robust, ground-dwelling stick insects (order Phasmatodea) from the subfamily Eurycanthinae, distributed in New Guinea, New Caledonia and associated islands. Its most famous member is the Lord Howe Island stick insect Dryococelus australis (Montrouzier), which was believed to have become extinct but was rediscovered in 2001 and is considered to be one of the rarest insects in the world. To resolve the evolutionary position of Dryococelus, we constructed a phylogeny from approximately 2.4 kb of mitochondrial and nuclear sequence data from representatives of all major phasmatodean lineages. Our data placed Dryococelus and the New Caledonian tree lobsters outside the New Guinean Eurycanthinae as members of an unrelated Australasian stick insect clade, the Lanceocercata. These results suggest a convergent origin of the ‘tree lobster’ body form. Our reanalysis of tree lobster characters provides additional support for our hypothesis of convergent evolution. We conclude that the phenotypic traits leading to the traditional classification are convergent adaptations to ground-living behaviour. Our molecular dating analyses indicate an ancient divergence (more than 22 Myr ago) between Dryococelus and its Australian relatives. Hence, Dryococelus represents a long-standing separate evolutionary lineage within the stick insects and must be regarded as a key taxon to protect with respect to phasmatodean diversity.     

The male genitalia of Oxyartes lamellatus - phasmatodeans do have complex phallic organs (Insecta: Phasmatodea)

A detailed study of the exoskeleton and musculature of the phallic organ of Oxyartes lamellatus (Kirby, 1904) (Phasmatodea: Necrosciinae) is here presented - the first study of this kind for Phasmatodea. The asymmetrical phallic organ shows a highly complicated morphology, with several sclerites and many formative structural elements, of which a sclerotised bulb in the ejaculatory duct wall and a long flagellum arising from near it are among the most conspicuous. Four extrinsic and 20 intrinsic phallic muscles were found; many of these are quite compact bundles or sheets, while a few others are diffuse groups of fibres. Phallic morphology in Oxyartes is compared with the literature data on male genitalia in other Phasmatodea, but this is limited by the superficial treatment of phallic organs in the few relevant previous contributions. Yet, phallic organs appear as a useful new character system for phylogenetic reconstruction and species distinction in Phasmatodea. Comparison with phallic organs in other ‘orthopteroid’ insects shows that these organs are too different among orders as to allow for sound homologisation of phallic substructures. Consideration of development of phallic organs does not help in this aspect. There is no evidence of phasmatodean phallic organs being pedomorphic.     

New species and new records of the subgenus Amiota s. str. Loew (Diptera: Drosophilidae) from North America,East Asia and Oceania

Fifteen known and five new species of the subgenus Amiota (s. str.) from North America, East Asia and Oceania were surveyed and described: A. leucostoma Loew, A. minor (Malloch), A. subtusradiata quadrata Takada & Toda and A. communis Chen & Steyskal, n. sp. from North America; A. aquilotaurinternatta Takada et a/., A. delta Takada et al., A. dentata Okada, A. elongata Okada, A. flagellata Okada, A. kamui Chen & Toda, A. palpitera Okada, A. spinata Chen & Toda, A. subturcata Okada, A. angulisternita Chen & Liu, n. sp. and A. kitamura Chen & Liu, n. sp. from Liaoning and Taiwan, China; biturcata Chen, n. sp. and A. vulnerabla Chen & Zhang, n. sp. each from Hokkaido and Kyushu, Japan, A. sinuata Okada, A. kimurai Chen & Toda and A. nagatai Okada from Papua New Guinea.     

广西十万大山(虫脩)目三新种((虫脩)目:异(虫脩)科,(虫脩)科)

报道采自广西十万大山Ｘｉｕ目３新种,即龙州蔷Ｘｉｕ Ａｓｃｅｌｅｓ ｌｏｎｇｚｈｏｕｅｎｓｉｓ Ｃｈｅｎ ｅｔ Ｈｅ,ｓｐ．ｎｏｖ．,斑角阿异Ｘｉｕ Ａｒｕａｎｏｉｄｅａ ｍａｃｕｌａｔａ Ｃｈｅｎ ｅｔ Ｈｅ,ｓｐ．ｎｏｖ。,和刺角短肛Ｘｉｕ Ｂａｃｕｌｕｍ ｓｐｉｎｉｃｏｒｎｕｍ Ｃｈｅｎ ｅｔ Ｈｅ,ｓｐ．ｎｏｖ．,与近似种作了比较,并附主要特征图。     

越南华枝属一新种(目：异科)

记述了华枝属Sinophasma Günther一新种越北华枝Sinophasma vietnamense新种。描述了新种的外部形态特征,并与近似种比较区别,附主要特征图。     

中国叶螩属记述(竹节虫目:叶螩科)

叶?在我国原记载2种,作者查看了采自江南7省区的标本30多件。共鉴定为8种,加上原有纪录的一未见种,我国总计9种,其中包括5新种和2种我国新纪录,本文主要记述4新种,属于丽叶?亚属的一新种已另文发表;并编制了我国产叶?的种检索表。 叶?多分布在雨量充沛地区,特别是热带岛屿,而本文中的泛叶?却采自远离海岸1200多km的贵州北部,以及藏叶?乃发现于北纬 29.2°的西藏墨脱,这对世界有关分类区系的研究,提供了新的资料。     

TWO NEW SPECIES OF STICK INSECTS FROM XIZANG AUTONOMOUS REGION (PHASMATODEA: PHASMATIDAE, HETEKONEMIIDAE)

Abstract  This paper deals with two new species of Phasmatodea from the Xizang Aut. Reg. belonging to Phasmatidae and Heteronemiidae. Their comparisons with close species and figures of characteristics are given.     

The pregenital abdominal musculature in phasmids and its implications for the basal phylogeny of Phasmatodea (Insecta: Polyneoptera)

Recently several conflicting hypotheses concerning the basal phylogenetic relationships within the Phasmatodea (stick and leaf insects) have emerged. In previous studies, musculature of the abdomen proved to be quite informative for identifying basal taxa among Phasmatodea and led to conclusions regarding the basal splitting events within the group. However, this character complex was not studied thoroughly for a representative number of species, and usually muscle innervation was omitted. In the present study the musculature and nerve topography of mid-abdominal segments in both sexes of seven phasmid species are described and compared in detail for the first time including all putative basal taxa, e.g. members of Timema, Agathemera, Phylliinae, Aschiphasmatinae and Heteropteryginae. The ground pattern of the muscle and nerve arrangement of mid-abdominal segments, i.e. of those not modified due to association with the thorax or genitalia, is reconstructed. In Timema, the inner ventral longitudinal muscles are present, whereas they are lost in all remaining Phasmatodea (Euphasmatodea). The ventral longitudinal muscles in the abdomen of Agathemera, which span the whole length of each segment, do not represent the plesiomorphic condition as previously assumed, but might be a result of secondary elongation of the external ventral longitudinal muscles. Sexual dimorphism, common within the Phasmatodea, also applies to the muscle arrangement in the abdomen of some species. Only in the females of Haaniella dehaanii (Heteropteryginae) and Phyllium celebicum (Phylliinae) the ventral external longitudinal muscles are elongated and span the length of the whole segment, possibly as a result of convergent evolution.     

中国长角枝(螩)亚科一新属及五新种((螩)目,笛(螩)科)

记述中国长角枝(螩)亚科1新属及5新种:微翅股(螩) Lopaphus micropterus sp.nov.,广东玛异(螩) Marmessoidea guangdongensis sp.nov.,树椿拟管(螩)Pseudosipyloidea shuchuni gen.et sp.nov.,大明山拟管(螩) Pseudosipyloidea damingshanensis gen.et sp.nov.及刺突臀(螩) Scionecra spinosa sp.nov..新种模式标本存放于上海昆虫博物馆及香港昆虫学会.