Taxonomic Study of Korean Stenopelmatoidea (Orthoptera: Ensifera)

ABSTRACT Eight species of the Stenopelmatoidea (Orthoptera: Ensifera) including two newly recorded Nippancistroger testaceus (Matsumura et Shiraki) and Anoplophilus acuticercus Karny are recognized in Korean fauna. Paratachycines (Hemitachycines) uenoi (Yamasaki) is proposed for junior synonym of Paratachycines (Hemitachycines) baldyrevi (Uvarov). The keys to species, characteristic figures and diagnoses for the newly recorded species are presented.     

The first fossil spider cricket (Orthoptera: Gryllidae: Phalangopsinae): 20 million years of troglobiomorphosis or exaptation in the dark?

A new spider cricket (Orthoptera: Gryllidae: Phalangopsinae) is described from an adult female preserved in Early Miocene (Burdigalian) amber from the Dominican Republic. Araneagryllus dylani gen. et sp. nov. represents the first fossil record of Phalangopsinae, and is assigned to the tribe Luzarini, subtribe Amphiacustina stat. nov. A cladistic analysis of Amphiacustina places Araneagryllus gen. nov. within a clade comprising Arachnopsita, Leptopedetes, Longuripes, Mayagryllus, Nemoricantor, and Prolonguripes. This clade is the sister group to a clade comprising Amphiacusta, Cantrallia, and Noctivox. The results of this analysis suggest that: (1) the common ancestor of all Amphiacustina was epigean, and was likely to have been cavicolous and/or straminicolous; (2) strict troglobitism evolved twice within Amphiacustina, once in the lineage leading to Noctivox and again in the clade comprising Mayagryllus, Arachnopsita, Longuripes, and Prolonguripes; and (3) Prolonguripes is secondarily epigean, having reverted to life above ground. The occurrence of Araneagryllus gen. nov. in amber indicates that it was not troglobitic, but was instead more likely to have been straminicolous, living on the ground and foraging amongst leaf litter. Araneagryllus gen. nov. possesses a number of characters that are usually considered to be adaptive to a troglobitic life history, suggesting that many so‐called troglobiomorphies are not adaptations to life in caves, but are instead likely to have been exaptive. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 158 , 56–65.     

A phylogenetic analysis of the adipokinetic neuropeptides of Ensifera

Abstract.  Adipokinetic neuropeptides, from the corpora cardiaca of various species of the suborder Ensifera, encompassing members of all superfamilies (except the Gryllacridoidea), were isolated by liquid chromatography, and identified structurally by comparison of retention times and mass spectrometry data with respect to information from known members of this peptide family. Ensiferan species always contain only one adipokinetic hormone (AKH) peptide, as assessed for a few species by monitoring typical AKH mass peaks from a crude corpora cardiaca extract. This AKH is an octapeptide, and is either Scg-AKH-II (pGlu-Leu-Asn-Phe-Ser-Thr-Gly-Trp amide) which occurs in all Tettigoniidea (except Schizodactyloidea) and in Gryllotalpoidea, or Grb-AKH (pGlu-Val-Asn-Phe-Ser-Thr-Gly-Trp amide) which occurs in Grylloidea (except Gryllotalpoidea) and Schizodactyloidea. Using the structural information of these neuropeptides in conjunction with morpho-anatomical characters, these data are interpreted in a phylogenetic framework. The lack of a decapeptide and the presence of the octapeptide Scg-AKH-II are ancestral in Ensifera. The ancestral Scg-AKH-II twice underwent an independent and convergent modification to Grb-AKH.     

直翅目昆虫分子系统学研究新进展

对1994年以来国内外在直翅目昆虫种群遗传变异及进化、种及种下阶元的分类鉴定、种上阶元的系统发育分析及分子进化等分子系统学方面的研究进展进行了综述。近年来,蝗亚目昆虫分子系统学方面的研究成果较为丰富,而有关螽亚目的分子系统学研究较少。线粒体基因和核基因序列联合分析、整个基因组全序列分析以及分子数据与形态学的密切结合将是分子系统学未来发展的主要研究手段。     

Sexually dimorphic antennal structures of New Zealand Cave Wētā (Orthoptera: Rhaphidophoridae)

Insect antennae carry diverse sensory organs for detecting information about their environments and facilitating interaction among individuals, particularly for reproductive behaviour. As such they are predicted to be sexually dimorphic, especially in species which do not use visual or auditory mate-location. The cave wētā are such animals, suggesting that they rely heavily on chemical and tactile information to interact. Sensilla morphology and sexual dimorphism was investigated in two species; Pachyrhamma acanthocera and P. waitomoensis, using scanning electron microscopy. Fourteen types of sensilla basiconica, campaniformia, chaetica, coeloconica, trichodea and Böhm’s sensilla were identified. Among these, sexual dimorphism in the length of four subtypes was detected, and surprisingly, P. waitomoensis males completely lacked all but two of the porous sensilla types. In addition, three types of unique horn-like and hooked antennal protrusions in male P. acanthocera are described, along with similar, but less diverse structures on the antennae of male P. waitomoensis.     

On the placement of the Cretaceous orthopteran Brauckmannia groeningae from Brazil, with notes on the relationships of Schizodactylidae (Orthoptera, Ensifera)

The fossil orthopteran Brauckmannia groeningae Martins-Neto (Orthoptera, Ensifera) from the Early Cretaceous Crato Formation of Brazil, currently misplaced at both the genus and family level, is transferred to the family Schizodactylidae and assigned to the extant genus Schizodactylus Brullé; ergo, Brauckmannia enters synonymy under Schizodactylus and Brauckmanniidae enters synonymy under Schizodactylidae. Schizodactylus groeningae (Martins-Neto), comb. n. agrees in size and general habitus with extant members of the genus, but can be readily separated by the robust, subovoid form of the metatibiae and the distinctive morphology of the lateral metabasitarsal processes. This species represents the first fossil occurrence of Schizodactylidae and the only New World record of this ancient lineage. Phylogenetic relationships of the schizodactylids are reviewed and a sister-group relationship with Grylloidea advocated based on a reappraisal of morphological and molecular evidence.     

High-frequency calling in Eneopterinae crickets (Orthoptera, Grylloidea, Eneopteridae): adaptive radiation revealed by phylogenetic analysis

The dominant frequency (Fd) of the cricket calling song commonly ranges from 2 to 8 kHz because of physical constraints due to small size and stridulum functioning. However some Eneopterinae crickets are known to call with Fds of 10–15 kHz, and one species ( Eneoptera guyanensis ) produces a modulated call with both a low and a high Fd. We studied Fd evolution with respect to phylogeny in the whole Eneopterinae subfamily to reconstruct its pattern of transformation. The phylogenetic pattern resulting from the analysis showed that Fd is relatively stable through the whole clade: the Fd ancestral state (3–7.9 kHz) has been modified only once, with the occurrence of a high Fd in the clade [ Cardiodactylus ( Lebinthus–Agnotecous )]: high Fd replaced low Fd, resulting in high-frequency calling songs. In E. guyanensis , the pattern of frequency change is different: a high Fd component has been added to the low ancestral Fd, resulting in frequency modulation. Investigation of cladogenesis rate indicated that the onset of high Fd in [ Cardiodactylus ( Lebinthus–Agnotecous )] was accompanied by a high cladogenesis rate, supporting a hypothesis of adaptive radiation for high-frequency calling (phylogeny criterion of adaptation). High frequencies are particularly problematic for long-range communication, especially for forest-living species, because of the increase of excess attenuation with frequency. The effectiveness of high-frequency calling is discussed in the clade [ Cardiodactylus ( Lebinthus–Agnotecous )] in relation to the behavioural ecology of the species.  © 2004 The Linnean Society of London, Biological Journal of the Linnean Society , 2004, 83 , 577–584.     

The secondary copulatory organ in female ground weta (Hemiandrus pallitarsis,Orthoptera: Anostostomatidae): a sexually selected device in females?

Secondary sexual devices in female insects, primarily abdominal modifications, appear to function as a means of thwarting coercive mating attempts by males or are, in rare cases, sexually selected adaptations. Female ground weta, Hemiandrus pallitarsis (Orthoptera: Anostostomatidae), have an elaborate elbowed device on the underside of the mid-abdomen. Experimental removal of this accessory organ shows that it does not increase the probability of mating as predicted by the thwart-copulation hypothesis. Instead, removal prevents copulation, thus demonstrating that it is a secondary copulatory device. The male attaches to the organ both at the beginning of copulation and at the end, when he positions himself to adhere a spermatophylax food gift onto the mid-ventral region of his mate. The female accessory organ does not function to manipulate eggs or larvae (females provide care to their single clutch of offspring) and is unlikely to be a copulatory structure that prevents hybridization. The great extent of the modification of the ventral abdominal segments of H. pallitarsis females compared to other Hemiandrus species is consistent with a history of sexual selection on the accessory organ. Taken together, these results and the finding that the length of the accessory organ of H. pallitarsis correlates with female fecundity, suggest that this structure evolved under sexual selection to acquire nuptial gifts from males.  © 2005 The Linnean Society of London, Biological Journal of the Linnean Society , 2005, 85 , 463–469.