Misplaced Pages

#602397

20-419: (But see text) Cercopidae are the largest family of Cercopoidea , a xylem -feeding insect group, commonly called froghoppers . They belong to the hemipteran suborder Auchenorrhyncha . A 2023 phylogenetic study of the family suggested the elevation of subfamily Ischnorhininae to full family status as Ischnorhinidae , leaving a monophyletic Cercopinae . Based on a 2023 molecular phylogenetic analysis,

40-421: A cover of foamed-up plant sap visually resembling saliva ; the nymphs are therefore commonly known as spittlebugs and their foam as cuckoo spit, frog spit, or snake spit. This characteristic spittle production is associated with the unusual trait of xylem feeding. Whereas most insects that feed on sap feed on the nutrient-rich fluid from the phloem , Cercopidae utilize the much more dilute sap flowing upward from

60-465: A group of hemipteran insects in the suborder Auchenorrhyncha . Adults are capable of jumping many times their height and length, giving the group their common name, but many species are best known for their plant-sucking nymphs which produce foam shelters, and are referred to as "spittlebugs". Membracoidea Cicadoidea Machaerotidae Clastopteridae Cercopidae Aphrophoridae (incl. Epipygidae ) Traditionally, most of this superfamily

80-412: A higher essential/non-essential amino acid ratio and lower osmotic pressure," or by feeding on the biomass of insects that have grown on more direct ingestion of phloem sap. Maple syrup is made from reduced sugar maple xylem sap. The sap often is harvested from the sugar maple, Acer saccharum . In some countries (e.g., Lithuania , Latvia , Estonia , Finland , Belarus , Russia ) harvesting

100-507: A mechanism for phloem sap transport, although other hypotheses have been proposed. Phloem sap is thought to play a role in sending informational signals throughout vascular plants. According to Annual Review of Plant Biology , Loading and unloading patterns are largely determined by the conductivity and number of plasmodesmata and the position-dependent function of solute -specific, plasma membrane transport proteins . Recent evidence indicates that mobile proteins and RNA are part of

120-480: A number of purposes. It hides the nymph from the view of predators and parasites, and it insulates against heat and cold, thus providing thermal control and also moisture control; without the foam, the insect would risk dehydration. The nymphs pierce plants and suck sap causing very little damage; much of the filtered fluids go into the production of the foam, which has an acrid taste, deterring predators. A few species are serious agricultural pests . A small family in

140-567: A watery solution of hormones , mineral elements and other nutrients . Transport of sap in xylem is characterized by movement from the roots toward the leaves . Over the past century, there has been some controversy regarding the mechanism of xylem sap transport; today, most plant scientists agree that the cohesion-tension theory best explains this process, but multiforce theories that hypothesize several alternative mechanisms have been suggested, including longitudinal cellular and xylem osmotic pressure gradients , axial potential gradients in

160-632: Is consumed as the dominant or sole diet by a very restricted range of animals". This apparent paradox is explained by the fact that phloem sap is physiologically extreme in terms of animal digestion, and it is hypothesized that few animals take direct advantage of this because they lack two adaptations that are necessary to enable direct use by animals. These include the existence of a very high ratio of non-essential / essential amino acids in phloem sap for which these adapted Hemiptera insects contain symbiotic microorganisms which can then provide them with essential amino acids; and also insect "tolerance of

180-426: Is distinct from latex , resin , or cell sap ; it is a separate substance, separately produced, and with different components and functions. Insect honeydew is called sap, particularly when it falls from trees, but is only the remains of eaten sap and other plant parts. Saps may be broadly divided into two types: xylem sap and phloem sap. Xylem sap (pronounced / ˈ z aɪ l ə m / ) consists primarily of

200-607: Is known from the late Middle Jurassic and early Late Cretaceous of Asia. The genus Qibinius the Middle Jurassic Yanan Formation of China mixes characters of both families and cannot be assigned to either. The genus Cercopion from the Aptian aged Crato Formation of Brazil appears to be derived from the Procerocopidae and closely related to the crown group . Sap (plant) Sap

220-630: The Cercopidae senso stricto was divided into two monophyletic subfamilies, Cercopinae and Cosmoscartinae , each with a number of tribes. Tribe Bandusiini Tribe Callitetixini Tribe Cercopini Tribe Haematoscartini Tribe Hemiaufidini Tribe Locrisini Tribe Rhinaulacini Tribe incertae sedis Tribe Considiini Tribe Cosmoscartini Tribe Phymatostethini Tribe Suracartini Tribe Trichoscartini Tribe incertae sedis Crispolon Jr et al. (2023) considered certain described genera as invalid without discussion and did not include them in

SECTION 10

#1732790690603

240-829: The family as prescribed by their phylogeny. Crispolon Jr. et al. s 2023 molocular phylogenetic analysis recommended removing the following genera from Cercopidae and transferring them to Aphrophoridae : Additionally they recommended the elevation of the subfamily Ischnorhininae , endemic to the Americas , to full family status as Ischnorhinidae . This was based on the closer phylogenetic ties to Machaerotidae then to subfamily Cercopinae found exclusively in Europe, Africa, and Asia, Australasia: Tribe Ischnorhinini Tribe Neaenini Tribe Tomaspini Cercopoidea The superfamily Cercopoidea , some members of which are called froghoppers and still others known as spittlebugs , are

260-787: The group, the Machaerotidae , known as the tube spittlebugs, is an outlier among the Cercopoidea because the nymphs live in calcareous tubes rather than producing foam as in the other families. Adult froghoppers jump from plant to plant; some species can jump up to 70 cm (28 in) vertically: a more impressive performance relative to body weight than fleas . The froghopper can accelerate at 4,000 m/s (13,000 ft/s ) over 2 mm (0.079 in) as it jumps (experiencing over 400 gs of acceleration). Spittlebugs can jump 100 times their own length. Many species of froghopper resemble leafhoppers , but can be distinguished by

280-446: The plant's long-distance communication signaling system. Evidence also exists for the directed transport and sorting of macromolecules as they pass through plasmodesmata. Many insects of the order Hemiptera (the half-wings), feed directly on phloem sap, and make it the primary component of their diet. Phloem sap is "nutrient-rich compared with many other plant products and generally lacking in toxins and feeding deterrents, [yet] it

300-417: The possession of only a few stout spines on the hind tibiae , where leafhoppers have a series of small spines. Members of the family Machaerotidae greatly resemble treehoppers , due to a large thoracic spine, but the spine in machaerotids is an enlargement of the scutellum , where treehoppers have the pronotum enlarged. Members of the family Clastopteridae have their wings modified to form false heads at

320-437: The roots via the xylem . The large amount of excess water that must be excreted and the evolution of special breathing tubes allow the young spittlebug nymphs to grow in the relatively protective environment of the spittle. Normally an animal should not be able to survive on a diet so low in nutrients, but the insects' digestive system contains symbiotic bacteria that provide them with the essential amino acids. The foam serves

340-602: The tail end, an antipredator adaptation. Many adult Cercopidae can bleed reflexively from their tarsi , and the hemolymph appears to be distasteful; they are often aposematically colored. The oldest froghoppers are known from the Early Jurassic . Mesozoic froghoppers are divided into two main families, Procercopidae known from the Early Jurassic to early Late Cretaceous of Asia, which are thought to be ancestral to living froghoppers, and Sinoalidae , which

360-431: The very high sugar content and osmotic pressure of phloem sap is promoted by their possession in the gut of sucrase - transglucosidase activity, which transforms excess ingested sugar into long-chain oligosaccharides ." A much larger set of animals do however consume phloem sap by proxy, either "through feeding on the honeydew of phloem-feeding hemipterans. Honeydew is physiologically less extreme than phloem sap, with

380-768: The vessels, and gel- and gas-bubble-supported interfacial gradients. Xylem sap transport can be disrupted by cavitation —an "abrupt phase change [of water] from liquid to vapor" —resulting in air-filled xylem conduits. In addition to being a fundamental physical limit on tree height, two environmental stresses can disrupt xylem transport by cavitation: increasingly negative xylem pressures associated with water stress , and freeze-thaw cycles in temperate climates. Phloem sap (pronounced / ˈ f l oʊ ɛ m / ) consists primarily of sugars , hormones, and mineral elements dissolved in water. It flows from where carbohydrates are produced or stored (sugar source) to where they are used (sugar sinks). The pressure flow hypothesis proposes

400-586: Was considered a single family, the Cercopidae , but this family has been split into three families for many years now: the Aphrophoridae , Cercopidae , and Clastopteridae . The family Epipygidae has been removed from the Aphrophoridae by some authors (e.g. ), but retained within Aphrophoridae by subsequent authors (e.g. ). These families are best known for the nymphal stage, which produces

#602397