A new discovery of a long-winged form of Mexican endemic grasshopper Melanotettix dibelonius Bruner, 1904 (Orthoptera: Acrididae: Gomphocerinae) and notes on wing polymorphism and geographic distribution

The species Melanotettix dibelonius Bruner, 1904 was previously recorded from Michoacán and Guerrero states in Mexico. This species is characterized by its tegmina, which are always shorter than head and pronotum together and sometimes shorter than the pronotum. After recent field expeditions (2015-2019) and an extensive review of museum specimens from the most important Orthoptera collections in Mexico and USA (291 specimens), we discovered a long-winged form of this species south of its previous known range, which effectively expanded its distribution range into Oaxaca state. We discuss some aspects regarding the patterns of geographic distribution and morphological variation among the long-winged and short-winged morphs. We conduct statistical analyses and observed that on average, the tegmina of long-winged individuals (both females and males) are slightly longer than twice the length of pronotum; whereas in short-winged individuals the tegmina are nearly as long or slightly longer than the length of the pronotum. Moreover, on average, females appear to have longer tegmina than males in both morphotypes. We provide photographic records of both forms live and mounted, the most comprehensive distribution map to date and a discussion of evolutionarily interesting patterns found in this species.

Application of Malaise traps to study the fauna of phytophagus beetles (coleoptera: chrysomeloidea, curculionoidea) of the Karadag nature reserve (republic of Crimea)

Analysis of the collection of beetles obtained using three Malaise traps during the field season of 2019 in the Karadag Nature Reserve revealed 46 species of phytophagous beetles from 6 families. Of these, 20 species for the fauna of Karadag were first indicated. Two species – Bruchus tristiculus (Bruchidae) and Alcidodes karelinii (Curculionidae) were first listed for the fauna of Crimea. In addition, according to an extensive series of specimens, the poorly studied winged form Longitarsus succineus (Foudras, 1860) (var. perfectus Weise, 1893) (Chrysomelidae) was first recorded in Crimea. In the sample is dominated by West-Central-Palaearctic species and West Palaearctic subboreal species, 9 species have Mediterranean or Pontic ranges (Luperus armeniacus, Phyllotreta aerea, Bruchus rufipes, B. tristiculus, Bruchidius dispar, Bradybatus seriesetosus, Otiorhynchus balcanicus, Polydrusus astutus, Eusomostrophus elongatus). Altogether, beetles from 27 families were collected by tent traps, while phytophagous beetles quantitatively prevailed over other groups of the order. The use of Malaise traps in different biotopes as an additional method for the stationary study of the local fauna of phytophagous beetles is recommended.

Revision of the leafhopper genus Gurawa (Cicadellidae: Deltocephalinae: Chiasmini) from Pakistan with description of a new species

The leafhopper genus Gurawa Distant, 1908 is revised with descriptions and illustrations of a new species, Gurawa longispina sp. nov. and a short winged form of Gurawa minorcephala Pruthi from Pakistan. A key is provided to distinguish known species in this genus from Pakistan.

Phasing of dragonfly wings can improve aerodynamic efficiency by removing swirl

Dragonflies are dramatic, successful aerial predators, notable for their flight agility and endurance. Further, they are highly capable of low-speed, hovering and even backwards flight. While insects have repeatedly modified or reduced one pair of wings, or mechanically coupled their fore and hind wings, dragonflies and damselflies have maintained their distinctive, independently controllable, four-winged form for over 300 Myr. Despite efforts at understanding the implications of flapping flight with two pairs of wings, previous studies have generally painted a rather disappointing picture: interaction between fore and hind wings reduces the lift compared with two pairs of wings operating in isolation. Here, we demonstrate with a mechanical model dragonfly that, despite presenting no advantage in terms of lift, flying with two pairs of wings can be highly effective at improving aerodynamic efficiency. This is achieved by recovering energy from the wake wasted as swirl in a manner analogous to coaxial contra-rotating helicopter rotors. With the appropriate fore–hind wing phasing, aerodynamic power requirements can be reduced up to 22 per cent compared with a single pair of wings, indicating one advantage of four-winged flying that may apply to both dragonflies and, in the future, biomimetic micro air vehicles.

PUCERONS NOUVEAUX ET PEU CONNUS DU MEXIQUE 4e NOTE: NOUVELLES ESPECES DE TUBERCULATUS SUBG. TOLTECALLIS SUBG. NOV. (HOM. APHIDIDAE)

Tuberculatus (Toltecallis) subg. nov. is characterized by the spiculation of the dorsal hairs of nymphs and by the basal pigmentation of the tibiae which differs from that of T. (Pacificallis). Three species are classified in the subgenus: T. (T.) mexicanus sp. n. (type of subgenus), distinguished by its long processus terminalis, T. (T.) garciamartelli sp. n. with spinal processes restricted to the two first abdominal segments and with short and thin spinal hairs on the embryo, and T. (T.) spiculatus Richards with processes on tergites I–IV and very long spinal setae on the embryo; the subspecies rebecae subsp. nov. of the last species has siphunculi and apical rostral segment longer and narrower at the base than in spiculatus s. str.The viviparous winged form, the embryo, and the alatoid nymph are described. The sexual forms are unknown. All the species live on Quercus in the central part of Mexico between an elevation of 2200 and 2700 m.