Bridging biotremology and chemical ecology: a new terminology.

Living organisms use both chemical and mechanical stimuli to survive in their environment. Substrate-borne vibrations play a significant role in mediating behaviors in animals and inducing physiological responses in plants, leading to the emergence of the discipline of biotremology. Biotremology is experiencing rapid growth both in fundamental research and in applications like pest control, drawing attention from diverse audiences. As parallels with concepts and approaches in chemical ecology emerge, there is a pressing need for a shared standardized vocabulary in the area of overlap for mutual understanding. In this article, we propose an updated set of terms in biotremology rooted in chemical ecology, using the suffix '-done' derived from the classic Greek word 'δονέω' (pronounced 'doneo'), meaning 'to shake'.

Adhesive properties of Aphrophoridae spittlebug foam.

Aphrophora alni spittlebug nymphs produce a wet foam from anal excrement fluid, covering and protecting themselves against numerous impacts. Foam fluid contact angles on normal (26°) and silanized glass (37°) suggest that the foam wets various substrates, including plant and arthropod surfaces. The pull-off force depends on the hydration state and is higher the more dry the fluid. Because the foam desiccates as fast as water, predators once captured struggle to free from drying foam, becoming stickier. The present study confirms that adhesion is one of the numerous foam characteristics resulting in multifunctional effects, which promote spittlebugs' survival and render the foam a smart, biocompatible material of biological, biomimetic and biomedical interest. The sustainable 'reuse' of large amounts of excrement for foam production and protection of the thin nymph integument suggests energetic and evolutionary advantages. Probably, that is why foam nests have evolved in different groups of organisms, such as spittlebugs, frogs and fish.

Adaptive shifts in Neotropical planthoppers: new troglobitic species and the first surface species of Ferricixius Hoch & Ferreira, 2012 (Hemiptera: Fulgoromorpha: Cixiidae) from Brazilian caves.

Here we describe three cixiid species new to science which we assign to the hitherto monotypic genus Ferricixius Hoch & Ferreira, 2012 from Brazil. Ferricixius michaeli sp. nov. and F. goliathi sp. nov. of the new species arelike the type species Ferricixius davidi Hoch &Ferreira, 2012obligately cavernicolous and display varying degrees of troglomorphy, such as the reduction of compound eyes, wings, and bodily pigmentation, while F. urieli sp. nov. displays well developed compound eyes and wings, andalthough so far only found inside cavesis ecologically classified as either epigean, or subtroglophile. We provide a modified diagnosis for the genus and an identification key to the species of Ferricixius, as well as information on the distribution, ecology, and habitat of the three new species herein described. Evolutionary implications are discussed, and adaptive shifts from epigean to subterranean habitat are presumed to be the most likely scenario underlying the evolution of cave dwelling Ferricixius.

Large abdominal mechanoreceptive sense organs in small plant-dwelling insects.

The Hemiptera, with approximately 98 000 species, is one of the largest insect orders. Most species feed by sucking sap from plant tissues and are thus often vectors for economically important phytopathogens. Well known within this group are the large cicadas (Cicadomorpha: Cicadoidea: Cicadidae) because they produce extremely loud airborne sounds. Less well known are their mostly tiny relatives, the leafhoppers, spittlebugs, treehoppers and planthoppers that communicate by silent vibrational signals. While the generation of these signals has been extensively investigated, the mechanisms of their perception are poorly understood. This study provides a complete description and three-dimensional reconstruction of a large and complex array of mechanoreceptors in the first abdominal segments of the Rhododendron leafhopper Graphocephala fennahi (Cicadomorpha: Membracoidea: Cicadellidae). Further, we identify homologous organs in the spittlebug Philaenus spumarius (Cicadomorpha: Cercopoidea: Aphrophoridae) and the planthopper Issus coleoptratus (Fulgoromorpha: Fulgoroidea: Issidae). Such large abdominal sensory arrays have not been found in any other insect orders studied so far. This indicates that these sense organs, together with the signal-producing tymbal organ, constitute a synapomorphy of the Tymbalia (Hemiptera excl. Sternorrhyncha). Our results contribute to the understanding of the evolution from substrate-borne to airborne communication in insects.

The genus Cixius Latreille, 1804 (Hemiptera, Fulgoromorpha, Cixiidae) in Lebanon with the description of two new species.

A first list of Cixius fauna of Lebanon is here provided with the description of two new species: one within the subgenus Acanthocixius, Cixius bifidispinus sp. nov. and one within the subgenus Ceratocixius Cixius superremotus sp. nov. The standard morphological description is supplemented by sequence data of the mitochondrial cytochrome c oxidase subunit I (COI) gene fragment. Some notes on their distribution and economic importance are also reported.

From micropterism to hyperpterism: recognition strategy and standardized homology-driven terminology of the forewing venation patterns in planthoppers (Hemiptera: Fulgoromorpha).

Following recent advances in the morphological interpretations of the tegmen basal cell margins in the Paraneoptera, a standardized and homology-driven groundplan terminology for tegmina types, structures and vein patterns in Hemiptera Fulgoromorpha, including fossils, is proposed. Each term is listed with a morphological definition, compared and linked to the main systems of planthopper forewing description that have been reviewed. The importance of a standardized and homology-driven terminology is stressed to enhance the quality of data in taxonomic descriptions and to strengthen phylogenetic morphological analysis results. When the interpretation of the origin of vein branches is render difficult, a three-step strategy for pattern recognition of the vein is proposed based on two principles: (1) vein forks are more informative than topology of the vein branches: a search for homologous areas, the nodal cells in particular, must first guide the recognition rather the number of branches of a vein, and (2) minimum of ad hoc evolutionary events should be invoked in the understanding of a modified vein pattern. Examples of some conflicting interpretations of venation patterns in planthoppers are discussed within different families for both extant and extinct taxa. For the first time, the concept of brachypterism is defined in a non-relative way independently from other structures, and the new one of hyperpterism is proposed; a reporting system is proposed for each of them.

Founder effects initiated rapid species radiation in Hawaiian cave planthoppers.

The Hawaiian Islands provide the venue of one of nature's grand experiments in evolution. Here, we present morphological, behavioral, genetic, and geologic data from a young subterranean insect lineage in lava tube caves on Hawai'i Island. The Oliarus polyphemus species complex has the potential to become a model for studying rapid speciation by stochastic events. All species in this lineage live in extremely similar environments but show strong differentiation in behavioral and morphometric characters, which are random with respect to cave age and geographic distribution. Our observation that phenotypic variability within populations decreases with increasing cave age challenges traditional views on founder effects. Furthermore, these cave populations are natural replicates that can be used to test the contradictory hypotheses. Moreover, Hawaiian cave planthoppers exhibit one of the highest speciation rates among animals and, thus, radically shift our perception on the evolutionary potential of obligate cavernicoles.

New replacement name for the planthopper genus Potiguara Hoch et Ferreira, 2013 (Hemiptera: Fulgoromorpha: Kinnaridae).

The Kinnaridae genus Potiguara was established by Hoch & Ferreira (2013) with the type species Potiguara troglobia Hoch et Ferreira, 2013 from Brazil. So far, this genus includes only the type species. Nevertheless, the name Potiguara is preoccupied and it was initially introduced by Machado et Brito, 2006 for an extinct genus of the fish family Pycnodontidae (with the type species Coelodus rosadoi Silva Santos, 1963 from Brazil). Thus, the genus Potiguara Hoch et Ferreira, 2013 is a junior homonym of the genus Potiguara Machado et Brito, 2006. According to Article 60 of the International Code of Zoological Nomenclature, we propose the new replacement name Kinnapotiguara nom. nov. for Potiguara Hoch et Ferreira, 2013. Accordingly, a new combination is herein proposed for the kinnarid planthopper species currently included in this genus: Kinnapotiguara troglobia (Hoch et Ferreira, 2013) comb. nov.

New species in the Old World: Europe as a frontier in biodiversity exploration, a test bed for 21st century taxonomy.

The number of described species on the planet is about 1.9 million, with ca. 17,000 new species described annually, mostly from the tropics. However, taxonomy is usually described as a science in crisis, lacking manpower and funding, a politically acknowledged problem known as the Taxonomic Impediment. Using data from the Fauna Europaea database and the Zoological Record, we show that contrary to general belief, developed and heavily-studied parts of the world are important reservoirs of unknown species. In Europe, new species of multicellular terrestrial and freshwater animals are being discovered and named at an unprecedented rate: since the 1950s, more than 770 new species are on average described each year from Europe, which add to the 125,000 terrestrial and freshwater multicellular species already known in this region. There is no sign of having reached a plateau that would allow for the assessment of the magnitude of European biodiversity. More remarkably, over 60% of these new species are described by non-professional taxonomists. Amateurs are recognized as an essential part of the workforce in ecology and astronomy, but the magnitude of non-professional taxonomist contributions to alpha-taxonomy has not been fully realized until now. Our results stress the importance of developing a system that better supports and guides this formidable workforce, as we seek to overcome the Taxonomic Impediment and speed up the process of describing the planetary biodiversity before it is too late.

Jumping behaviour in a Gondwanan relict insect (Hemiptera: Coleorrhyncha: Peloridiidae).

Jumping by a relict insect, Hackeriella veitchi (Hacker 1932), belonging to the ancient Coleorrhynchan line that diverged from other Hemiptera in the late Permian, was analysed from high-speed images captured at rates of 2000 s(-1) and from its anatomy. This 3 mm long, flightless insect weighs up to 1.4 mg and can jump by rapid movements of the hind legs that accelerate the body in 1.5 ms to a take-off velocity of 1.5 m s(-1). This performance requires an energy expenditure of 1.1 microJ and a power output 0.74 mW, and exerts a force of 1.24 mN. It achieves this with a body design that shows few specialisations for jumping compared with those of other groups of Hemipterans such as the froghoppers or leafhoppers. The hind legs are only 10% longer than the front and middle legs by virtue of longer tibiae and tarsi, and are only 65% the length of the body. The main thrust for a jump is provided by the rapid rotation of the fused trochanter and femur about the coxa of a hind leg, in a movement that forces the hind tarsus against the ground and raises the body to take off. In some jumps the two hind legs move together, but in others the movements may not be closely synchronised, thereby imparting a rotation on the body that is maintained once airborne. When the time difference is larger, the rapid movement of just one hind leg results in the insect falling from its perch in an adaptive escape response.

Vibrational signalling in a Gondwanan relict insect (Hemiptera: Coleorrhyncha: Peloridiidae).

Ancient, long-extinct floras and faunas can be reassembled through fossils and phylogenetics, and even palaeo-environments can be reconstructed with the aid of palaeoclimatology. However, very little is known about the sound-scape of the past. Of what kind were the first biologically meaningful sounds and vibrations ever emitted and perceived? The earliest signals in the history of life were probably produced by arthropods making use of the mechanical properties of their exoskeleton. Here, we report an observation of vibrational signalling in the coleorrhynchan Hackeriella veitchi, a representative of a Gondwanan relict insect lineage which is still extant in the Queensland rainforest. Our finding suggests that vibrational signalling by tymbal organs is ancestral for the Hemiptera (exclusive of Sternorrhyncha)--the song of the Coleorrhyncha was a likely element of the acoustic environment in the Permian moss forests and had possibly changed little since.