Evolution of chromosome number in grasshoppers (Orthoptera: Caelifera: Acrididae)

Organisms Diversity & Evolution - Orthoptera have some of the largest genomes of all insects. At the same time, the architecture of their genomes remains poorly understood. Comparative...     

Taxonomic Study of Korean Chrysochraontini (Orthoptera: Acrididae: Gomphocerinae)

Five species of Korean Chrysochraontini are recognized through the taxonomic investigation. Among them Chrysochraon dispar major Uvarov, 1925 is newly recorded from North Korea, and Euthystira pavlovskii Bey‐Bienko, 1954 is synonymized under Mongolotettix japonicus (Bolívar, 1898). A key is provided, and morphological variations of M. japonicus are discussed.     

Development,reproductive capacity and diet of the Mediterranean grasshopper Arcyptera brevipennis vicheti Harz 1975 (Orthoptera: Caelifera: Acrididae: Gomphocerinae)

Arcyptera brevipennis vicheti Harz 1975 (Orthoptera: Acrididae) is a rare grasshopper native to Mediterranean grassland habitats in the Languedoc-Roussillon region of southern France. Changes in land-use have modified these unique habitats, thus threatening the survival of A. b. vicheti populations. To improve the conservation of this species this study aimed to describe important aspects of its biology and ecology. Development of nymphs passed through five instars after hatching and was closely associated with the Mediterranean spring season. A prominent sexual size dimorphism is highlighted, but the larger females developed in the same number of instars as males. Hind femur length and number of antenna segments were useful characters when distinguishing between nymphal instars. All individuals were brachypterous, indicating that A. b. vicheti is unable to fly. Adult females laid 15 eggs on average and deposited no more than two egg pods in their lifetime. Grass debris made up 93% of faecal content of both sexes. Our results provide valuable information for the conservation of this highly endangered grasshopper species.     

Molecular phylogeny of Palaearctic genera of Gomphocerinae grasshoppers (Orthoptera, Acrididae)

Abstract.  Molecular phylogenetic methods were used to examine morphologically based hypotheses concerning the taxonomic structure and relationships of the grasshopper subfamily Gomphocerinae. Two mitochondrial gene (cytochrome b and cytochrome oxidase subunit I) sequences were determined for twenty-five species representing eleven Palaearctic genera. The studied Gomphocerinae species constituted a monophyletic group; furthermore, the earlier division of Gomphocerinae into tribes was supported, with each tribe monophyletic. There was no support for various systems uniting Stenobothrini and Gomphocerini into one tribe. Two separate clusters were discerned in Gomphocerini and two tribes were distinguished – Gomphocerini (genera Aeropus , Stauroderus , Chorthippus ) and Stenobothrini (genera Omocestus , Stenobothrus ).     

Vibration communication in orthopteroid insects (Orthoptera) from suborder Caelifera

A review of vibration communication in suborder Caelifera is made. The vibration communication channel is found in three superfamilies—Tetrigoidea, Eumastacoidea and Acridoidea. The presence of vibration communication in Pyrgomorphoidea and Tridactyloidea is suggested. The data on vibration signals in superfamilies Pneumoroidea, Tanaoceroidea and Trigonopterygoidea are not known.     

Recognition of sex in the acoustic communication of the grasshopper Chorthippus biguttulus (Orthoptera, Acrididae)

Many gomphocerine grasshoppers communicate acoustically: a male's calling song is answered by a female which is approached phonotactically by the male. Signals and recognition mechanisms were investigated in Chorthippus biguttulus with regard to the cues which allow sex discrimination. (1) The stridulatory files on the hindfemur of both sexes are homologous in that they are derived from the same row of bristles, but convergent with respect to the “pegs”. In males the pegs are derived from the bristles, and in females from the wall of the bristle's cup. (2) Male and female songs are generated by similar, probably homologous motor programs, but differ in the duration, intensity, “gappyness” of syllables, risetime of pulses, and the frequency spectra. The hindleg co-ordination during stridulation and the resulting temporal song patterns are less variable in males than in females. (3) For both sexes, recognition of a mate's signal depends on species-specific syllable structure. For males it is essential that the female syllables consist of distinct short pulses, whereas females reject “gappy” syllables. Males strongly prefer “ramped” pulses, females respond to syllables irrespective of steeply or slowly rising ramps. Males react only to the low-frequency component, whereas females prefer spectra containing both, low and high frequency components. Accepted: 20 November 1996     

Variation in sperm precedence in Chorthippus grasshoppers (Caelifera: Gomphocerinae)

Variation in the proportions of offspring fathered by a second male to mate (the P₂ value) has been studied in two species of grasshoppers, Chorthippus parallelus (Zetterstedt) and Ch. biguttulus (Linnaeus), by means of the sterile‐male technique. In both species the P₂‐values of the first egg pods laid were in the range of 50–100%, and the temporal variation of P₂‐values appeared to follow two modes. In one, the P₂‐value steadily declined with time, in the other it remained constant at a high level. It is concluded that sperm is passively lost between two matings. The remaining sperm then either mixes within the spermatheca or is stratified. Further variability in sperm precedence can possibly be explained by spermatophore ejection or differential use of stored sperm.     

The complete mitochondrial genome of Gomphocerus tibetanus Uvarov, 1935 (Orthoptera: Acrididae: Gomphocerinae)

The complete nucleotide sequence of the mitochondrial genome (mitogenome) of Gomphocerus tibetanus Uvarov, 1935 (Orthoptera: Acrididae: Gomphocerinae) was determined. It is 15,571 bp in length and contains 74.8% A + T. All Gomphocerus tibetanus protein-coding sequences start with a typical ATN codon. The usual termination codons (TAA and TAG) were found from 13 PCGs except COI and COII which took incomplete codon T as termination codons. All tRNA genes could be folded into the typical cloverleaf secondary structure, except tRNA^Ser(AGN) lacking of dihydrouridine (D) arm. The sizes of the large and small ribosomal RNA genes are 1313 and 822 bp, respectively. The A + T content of the A + T-rich region is 82.3%. A preliminary analysis on characteristics of Gomphocerinae mitogenome was made by comparision among three Gomphocerinae mitogenomes and Locusta migratoria.     

Stable and variable parameters in courtship songs of grasshoppers of the subfamily Gomphocerinae (Orthoptera,Acrididae)

The courtship behavior of seven grasshopper species of the subfamily Gomphocerinae from different localities of Russia, Ukraine and Greece was described. Not only the sounds but also the corresponding stridulatory movements of the hind legs and visual display accompanying the courtship song were analyzed. Comparison of the degree of variation in different courtship parameters showed that the most stable traits were the syllable and pulse periods. The potential role of stable and variable traits in the grasshopper courtship songs is discussed.     

A new Phonogaster grasshopper from China (Acrididae: Gomphocerinae)

Abstract. Phonogaster longigeniculata sp.n. is described from five males and four females collected on mountain slopes at Wang-Mo, Guizhou Province. Prior to the discovery of this species, Phonogaster was a monobasic genus, its single included species, cariniventris Henry, known only from southern India.     

欧亚大陆癞蝗科分类系统(直翅目:蝗亚目)

对分布于欧亚大陆的癞蝗科Pamphagidae昆虫进行了亚科分类研究,将已知的47个属分为6个亚科:锯癞蝗亚科Prionotropisinae nov.,蠢蝗亚科Thrinchinae,癞蝗亚科Pamphaginae,鸣癞蝗亚科Tropidaucheninae nov.,聋癞蝗亚科Nocarodesinae nov.,秃癞蝗亚科Orchaminae nov.,其中包括4个新亚科。建立了欧亚大陆癞蝗科新的分类系统。     

欧亚大陆斑翅蝗科分类系统(直翅目: 蝗亚目)

对分布在欧亚大陆的斑翅蝗科Oedipodidae昆虫进行了亚科分类研究, 将已知的69个属分为7个亚科: 飞蝗亚科Locustinae, 斑翅蝗亚科Oedipodinae, 异距蝗亚科Heteropterninae subfam. n., 痂蝗亚科Bryodeminae, 异痂蝗亚科Bryodemellinae, 哑斑翅蝗亚科Oedipodacrinae subfam. n.和聋斑翅蝗亚科Rashidinae subfam. n., 其中包括3个新亚科。建立了欧亚大陆斑翅蝗科新的亚科分类系统。     

Costs and Benefits of Mating in the Grasshopper Chorthippus parallelus (Caelifera: Acrididae)

Fitness consequences of different levels of mating benefits, viz., (1) virgin, (2) seldom mated, (3) free mating chances with the same male throughout the female's life span, and (4) free mating chances with three males always offered, were investigated in female meadow grasshoppers Chorthippus parallelus. No differences among the treatments were apparent in egg number per pod, total egg number per female, and hatching success of larvae. Seldom-mated females had offspring with the heaviest average larval dry weight. We did not find costs of mating in terms of reduced female longevity and residual dry weight between the treatments.     

Pharmacological Activation of Stridulation in the Grasshopper Chorthippus albomarginatus (Orthoptera: Gomphocerinae)

Calling and courtship stridulatory behavior of Chorthippus albomarginatus was induced by injections of acetylcholine agonists into the protocerebrum. Pharmacologically induced stridulation, in many parameters, was quite similar to the natural behavior. However, the order of the courtship element alternation was different from that of the natural song. In some cases the pharmacologically induced stridulation included only one or two courtship elements. Based on the exclusive stimulation of a particular element of courtship songs and similarity of its movement pattern with the calling song, both patterns of Ch. albomarginatus stridulation appear to be homologous. The results obtained on this species confirm the idea of a hierarchic organization of the central nervous control of stridulation in gomphocerine grasshoppers and indicate participation of certain protocerebrum structures in this control.     

Transmission and perception of acoustic signals in the desert clicker,Ligurotettix coquilletti (Orthoptera: Acrididae)

Males of the desert clicker, Ligurotettix coquilletti (Acrididae: Orthoptera) defend a femalerequired resource, the creosote bush Larrea tridentata, in desert habitats of the southwestern United States. Males signal acoustically to each other as well as to searching females. The call is produced by tegminal/femoral stridulation where one or both legs are used for sound production. Sound pressure levels, measured laterally, are influenced by the intervening tegmen between the stridulating leg and the microphone. Differences in measured sound pressure levels between sides can vary up to 7 dB. When clicks are produced multiply,these multiple clicks may be 4 dB louder than single clicks. We examine the structure of the call and the effective broadcast area of single males by monitoring acoustic ascending neurons of the ventral nerve cord in the neck. By taking the neurophysiological preparation into the field, we were able to map the broadcast area of isolated males and also of males calling within aggregations. The distance over which the signal of isolated males could be detected was 8–14 m, whereas neural representation of the calls of males within aggregation were detectable within 4–6 m. The sound spectrum of the song, although having a major lower-frequency component around 10 kHz, has extensive power in the ultrasonic range. The tuning characteristics of the ascending auditory neuron matched the overall structure of the male call. The importance of the acoustic cue, as compared to visual cues, is discussed in relation to female attraction.     

New Tridactyloidea in Miocene amber from the Dominican Republic (Orthoptera: Caelifera)

Two new Tridactyloidea of the families Ripipterygidae and Tridactylidae are described from the Early Miocene (Burdigalian) amber of the Dominican Republic, namely: Archaeoellipes engeli n. gen., n. sp. (Tridactylidae: Tridactylinae) and Mirhipipteryx antillarum n. sp. (Ripipterygidae). These new taxa represent the fi rst record of Tridactyloidea in Dominican amber and the fi rst fossil record of Ripipterygidae, which are otherwise known only from the extant fauna.