''Panoploscelis'' (commonly referred to as spiny lobster katydids or giant lobster crickets) is a
genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...
of very large
insect
Insects (from Latin ') are pancrustacean hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body ( head, thorax and abdomen), three pairs ...
s belonging to the
true katydid
The subfamily Pseudophyllinae contains numerous species in the family Tettigoniidae, the katydids or bush crickets. Sometimes called "true katydids", together with the cricket (insect), crickets of suborder Ensifera, they form part of the insect ...
tribe
The term tribe is used in many different contexts to refer to a category of human social group. The predominant worldwide usage of the term in English language, English is in the discipline of anthropology. This definition is contested, in p ...
Eucocconotini, which is a
subfamily
In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end subfamily botanical names with "-oideae", and zoologi ...
of the
katydids
Insects in the family Tettigoniidae are commonly called katydids (especially in North America), or bush crickets. They have previously been known as "long-horned grasshoppers". More than 8,000 species are known. Part of the suborder Ensifera, t ...
. Like the other members of the suborder
Ensifera
Ensifera is a suborder of insects that includes the various types of crickets and their allies including: true crickets, camel crickets, bush crickets or katydids, grigs, weta and Cooloola monsters. This and the suborder Caelifera (grassh ...
, ''Panoploscelis'' are part of the insect
order Orthoptera
Orthoptera () is an order of insects that comprises the grasshoppers, locusts, and crickets, including closely related insects, such as the bush crickets or katydids and wētā. The order is subdivided into two suborders: Caelifera – grassho ...
, which also contains
crickets
Crickets are orthopteran insects which are related to bush crickets, and, more distantly, to grasshoppers. In older literature, such as Imms,Imms AD, rev. Richards OW & Davies RG (1970) ''A General Textbook of Entomology'' 9th Ed. Methuen 8 ...
,
grasshopper
Grasshoppers are a group of insects belonging to the suborder Caelifera. They are among what is possibly the most ancient living group of chewing herbivorous insects, dating back to the early Triassic around 250 million years ago.
Grasshopp ...
s and
locust
Locusts (derived from the Vulgar Latin ''locusta'', meaning grasshopper) are various species of short-horned grasshoppers in the family Acrididae that have a swarming phase. These insects are usually solitary, but under certain circumstanc ...
s. Members of this genus are among the largest katydids of the
Neotropics
The Neotropical realm is one of the eight biogeographic realms constituting Earth's land surface. Physically, it includes the tropics, tropical Ecoregion#Terrestrial, terrestrial ecoregions of the Americas and the entire South American temperat ...
.
These
terrestrial
Terrestrial refers to things related to land or the planet Earth.
Terrestrial may also refer to:
* Terrestrial animal, an animal that lives on land opposed to living in water, or sometimes an animal that lives on or near the ground, as opposed to ...
,
predatory
Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill th ...
insects are
endemic
Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...
to the remote and relatively inaccessible
neotropical rainforests of
Central
Central is an adjective usually referring to being in the center of some place or (mathematical) object.
Central may also refer to:
Directions and generalised locations
* Central Africa, a region in the centre of Africa continent, also known as ...
and
South America
South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the southe ...
. Little is known about this genus, because data thus far have been collected from a very limited number of specimens. The first specimen, a female of the species ''
P. armata'', was described in 1869 by
Samuel Hubbard Scudder
Samuel Hubbard Scudder (April 13, 1837 – May 17, 1911) was an American entomologist and paleontologist. He was a leading figure in entomology during his lifetime and the founder of insect paleontology in America. In addition to fossil insects, ...
.
[ The male of the species '' P. specularis'' was described for the first time in 2003.][
]
Taxonomy
The subfamily Pseudophyllinae was first described by Hermann Burmeister
Karl Hermann Konrad Burmeister (also known as Carlos Germán Conrado Burmeister) (15 January 1807 – 2 May 1892) was a German Argentine zoologist, entomologist, herpetologist, botany, botanist, and coleopterologist. He served as a professor at ...
in 1838. The tribe Eucocconotini was first described by Max Beier
Max Beier (6 April 1903 in Spittal an der Drau – 4 July 1979 in Vienna) was an Austrian arachnologist and entomologist.
He studied zoology at the University of Vienna, and obtained his doctorate there in 1927. He took up a post at the Natural H ...
in 1960. There are currently four recognized species of ''Panoploscelis'':
*'' P. angusticauda'' (Beier, 1950)[Beier M 1950. Das Genus Panoploscelis Scudder (Orthot.-Pseudophyllinae). Proceedings of the 8th International Congress of Entomology, Stockholm, 1948. 111-115.]
*'' P. armata'' (Scudder, 1869)[
*'' P. scudderi'' (Beier, 1950)][
*'' P. specularis'' (Beier, 1950)][
]
Distribution
All species of ''Panoploscelis'' are endemic to the neotropical rainforests of Colombia, Ecuador, Peru, Brazil, and Guyana, especially in the higher drainage
Drainage is the natural or artificial removal of a surface's water and sub-surface water from an area with excess of water. The internal drainage of most agricultural soils is good enough to prevent severe waterlogging (anaerobic conditio ...
of the Amazon River
The Amazon River (, ; es, Río Amazonas, pt, Rio Amazonas) in South America is the largest river by discharge volume of water in the world, and the disputed longest river system in the world in comparison to the Nile.
The headwaters of t ...
.
Morphology
Like many other arthropod
Arthropods (, (gen. ποδός)) are invertebrate animals with an exoskeleton, a Segmentation (biology), segmented body, and paired jointed appendages. Arthropods form the phylum Arthropoda. They are distinguished by their jointed limbs and Arth ...
s, these insects have an exoskeleton
An exoskeleton (from Greek ''éxō'' "outer" and ''skeletós'' "skeleton") is an external skeleton that supports and protects an animal's body, in contrast to an internal skeleton (endoskeleton) in for example, a human. In usage, some of the ...
composed largely of sclerotin
Sclerotin is a component of the cuticle of various Arthropoda, most familiarly insects. It is formed by cross-linking members of particular classes of protein molecules, a biochemical process called sclerotization, a form of tanning in which qu ...
. The cuticle
A cuticle (), or cuticula, is any of a variety of tough but flexible, non-mineral outer coverings of an organism, or parts of an organism, that provide protection. Various types of "cuticle" are non- homologous, differing in their origin, structu ...
and sclerite
A sclerite (Greek , ', meaning "hard") is a hardened body part. In various branches of biology the term is applied to various structures, but not as a rule to vertebrate anatomical features such as bones and teeth. Instead it refers most commonly ...
s are reddish-brown in color, with the dorsal surfaces being more deeply pigmented than the ventral
Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek language, Greek roots, describe something in its standard anatomical position. Th ...
.
As with all katydids, these insects have one pair of forewings (referred to as tegmina
A tegmen (plural: ''tegmina'') designates the modified leathery front wing on an insect particularly in the orders Dermaptera ( earwigs), Orthoptera (grasshoppers, crickets and similar families), Mantodea (praying mantis), Phasmatodea (stick an ...
) and one pair of hindwings. In contrast to many other katydids however, the tegmina of ''Panoploscelis'' only partly cover the hindwings. The hindwings themselves are vestigial
Vestigiality is the retention, during the process of evolution, of genetically determined structures or attributes that have lost some or all of the ancestral function in a given species. Assessment of the vestigiality must generally rely on co ...
, extending only roughly 25% the length of the abdomen. These massive brachypterous
Brachyptery is an anatomical condition in which an animal has very reduced wings. Such animals or their wings may be described as "brachypterous". Another descriptor for very small wings is microptery.
Brachypterous wings generally are not functi ...
insects are therefore incapable of flight.
The tibia
The tibia (; ), also known as the shinbone or shankbone, is the larger, stronger, and anterior (frontal) of the two bones in the leg below the knee in vertebrates (the other being the fibula, behind and to the outside of the tibia); it connects ...
is longer than the femur
The femur (; ), or thigh bone, is the proximal bone of the hindlimb in tetrapod vertebrates. The head of the femur articulates with the acetabulum in the pelvic bone forming the hip joint, while the distal part of the femur articulates with ...
in all three pairs of limbs; the combined length of these structures exceeds the length of the body in the case of the hindlimb
A hindlimb or back limb is one of the paired articulated appendages (limbs) attached on the caudal ( posterior) end of a terrestrial tetrapod vertebrate's torso.http://www.merriam-webster.com/medical/hind%20limb, Merriam Webster Dictionary-Hindl ...
s. Short cerci are present in both sexes. The antennae are filamentous and exceed the length of the body.
There is significant sexual dimorphism
Sexual dimorphism is the condition where the sexes of the same animal and/or plant species exhibit different morphological characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most ani ...
in the genus. The males can measure up to in length, while females are slightly longer at . The subgenital plate is longer in the male than in the female. Females are easily distinguished from males by the presence of a large, sword-shaped ovipositor
The ovipositor is a tube-like organ used by some animals, especially insects, for the laying of eggs. In insects, an ovipositor consists of a maximum of three pairs of appendages. The details and morphology of the ovipositor vary, but typical ...
which measures nearly half the length of the body.[
]
Tegminal sound generator
Katydids produce acoustical signals by rubbing their tegmina together, a mechanism referred to as tegminal stridulation
Stridulation is the act of producing sound by rubbing together certain body parts. This behavior is mostly associated with insects, but other animals are known to do this as well, such as a number of species of fish, snakes and spiders. The mech ...
(first described by Dumortier in 1963). Male Pseudophyllinae katydids (and females of some species, such as ''Pterophylla camellifolia
''Pterophylla camellifolia'', the common true katydid, is a common North American insect in the family Tettigoniidae (katydids). Within the Tettigoniidae, it belongs to the subfamily Pseudophyllinae (true katydids). Other common names include ...
'') have stridulatory apparati on their tegmina for generating such signals. This is thought to be a means for social communication
Communication (from la, communicare, meaning "to share" or "to be in relation with") is usually defined as the transmission of information. The term may also refer to the message communicated through such transmissions or the field of inquir ...
such as the attraction of a mate, and also to protest when disturbed by a potential predator or other animal. The presence of sophisticated hearing organs in both males and females supports the assertion that communication by sound plays an important role in the lives of the ''Panoploscelis''.
Both male and female ''Panoploscelis'' insects possess asymmetric tegmina upon which fully developed stridulatory organs are located. In the males of the genus ''Panoploscelis'', the tegminal stridulatory organ consists of a file
File or filing may refer to:
Mechanical tools and processes
* File (tool), a tool used to ''remove'' fine amounts of material from a workpiece
**Filing (metalworking), a material removal process in manufacturing
** Nail file, a tool used to gent ...
, a scraper
Scrape, scraper or scraping may refer to:
Biology and medicine
* Abrasion (medical), a type of injury
* Scraper (biology), grazer-scraper, a water animal that feeds on stones and other substrates by grazing algae, microorganism and other matter ...
(referred to as a plectrum
A plectrum is a small flat tool used for plucking or strumming of a stringed instrument. For hand-held instruments such as guitars and mandolins, the plectrum is often called a pick and is held as a separate tool in the player's hand. In harpsic ...
), and an amplification device, as is found in other katydids. The file—consisting of a transverse vein
Veins are blood vessels in humans and most other animals that carry blood towards the heart. Most veins carry deoxygenated blood from the tissues back to the heart; exceptions are the pulmonary and umbilical veins, both of which carry oxygenated b ...
with a single row of teeth—is located on the right wing, while the scraper consists of the sharply upturned right edge of the left wing. The thin glassy membrane of both wings, especially the larger left wing, functions as a diaphragm or drumhead
A drumhead or drum skin is a membrane stretched over one or both of the open ends of a drum. The drumhead is struck with sticks, mallets, or hands, so that it vibrates and the sound resonates through the drum.
Additionally outside of percus ...
to amplify the sound that is produced when the file is moved over the scraper.
In contrast to the single file of the male, females of the genus ''Panoploscelis'', however, have anywhere from three to six such files (crossveins) on the right wing, depending on the species.[
]
''P. specularis''
It is relatively easy to distinguish ''P. specularis'' from the other three species, because only in this species is the distal
Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position pro ...
spine of the fore femur directed anteriorly. Also, the fastigium frontis is tubercular and obtuse in this species, where it is spiniform and acute in the other three species. Another distinguishing feature is that there is a small tubercle
In anatomy, a tubercle (literally 'small tuber', Latin for 'lump') is any round nodule, small eminence, or warty outgrowth found on external or internal organs of a plant or an animal.
In plants
A tubercle is generally a wart-like projection ...
or nodule on the medioventral portion of the scape (the first or basal segment) of the antenna of ''P. specularis'', in contrast to the erect distal spine in this location in the other three species. Finally, the dorsal
Dorsal (from Latin ''dorsum'' ‘back’) may refer to:
* Dorsal (anatomy), an anatomical term of location referring to the back or upper side of an organism or parts of an organism
* Dorsal, positioned on top of an aircraft's fuselage
* Dorsal co ...
surface of the femora are unarmed (lacking in spines) in this species, whereas the other three species possess spines at this location.
Behavior and ecology
''Panoploscelis'' are terrestrial, predatory insects which dwell in the humid understory
In forestry and ecology, understory (American English), or understorey (Commonwealth English), also known as underbrush or undergrowth, includes plant life growing beneath the forest canopy without penetrating it to any great extent, but abov ...
of the Amazon rainforest
The Amazon rainforest, Amazon jungle or ; es, Selva amazónica, , or usually ; french: Forêt amazonienne; nl, Amazoneregenwoud. In English, the names are sometimes capitalized further, as Amazon Rainforest, Amazon Forest, or Amazon Jungle. ...
. They are nocturnally active, foraging for food at night.[ They are mostly ]herbivorous
A herbivore is an animal anatomically and physiologically adapted to eating plant material, for example foliage or marine algae, for the main component of its diet. As a result of their plant diet, herbivorous animals typically have mouthpart ...
, although opportunistic carnivory
A carnivore , or meat-eater (Latin, ''caro'', genitive ''carnis'', meaning meat or "flesh" and ''vorare'' meaning "to devour"), is an animal or plant whose food and energy requirements derive from animal tissues (mainly muscle, adipose tissue, f ...
has been observed;[ their diet includes leaves and small insects.][ They often leave a characteristic pattern of holes, arranged in a straight line horizontally across leaves upon which they have fed. They typically return just prior to dawn to a designated and well-concealed resting place within vegetation or ]leaf litter
Plant litter (also leaf litter, tree litter, soil litter, litterfall or duff) is dead plant material (such as leaves, bark, needles, twigs, and cladodes) that have fallen to the ground. This detritus or dead organic material and its constituent ...
, where they remain throughout the day.
Defensive adaptations
An important source of nutrition for many vertebrate
Vertebrates () comprise all animal taxa within the subphylum Vertebrata () ( chordates with backbones), including all mammals, birds, reptiles, amphibians, and fish. Vertebrates represent the overwhelming majority of the phylum Chordata, ...
s, including birds, bats, snakes, lizards and monkeys, katydids are a critical link in the food chain in their biome
A biome () is a biogeographical unit consisting of a biological community that has formed in response to the physical environment in which they are found and a shared regional climate. Biomes may span more than one continent. Biome is a broader ...
. Intense predatory pressure from these animals has forced these insects to evolve certain morphological and behavioral defensive defenses to avoid predation by other animals. Primary defensive adaptations are employed to avoid potential predators, while secondary adaptations are used only after the insect has been disturbed or provoked.[
Primary defensive adaptations against diurnally active predators such as ]monkeys
Monkey is a common name that may refer to most mammals of the infraorder Simiiformes, also known as the simians. Traditionally, all animals in the group now known as simians are counted as monkeys except the apes, which constitutes an incomple ...
include the use of camouflage
Camouflage is the use of any combination of materials, coloration, or illumination for concealment, either by making animals or objects hard to see, or by disguising them as something else. Examples include the leopard's spotted coat, the ...
such as the brown color of their bodies, and concealment within vegetation or debris on the forest floor. Primary defensive adaptations against nocturnally active acoustically orienting predators such as leaf-nosed bat
The New World leaf-nosed bats (Phyllostomidae) are found from southern North America to South America, specifically from the Southwest United States to northern Argentina. They are ecologically the most varied and diverse family within the order ...
s and other foliage-gleaners include the use of stridulatory signals characterized by a single tone at high frequency and of short duration.
Secondary defensive adaptations include acoustical alarm displays,[ regurgitation of material from the stomach, and the use of their powerful ]mandibles
In anatomy, the mandible, lower jaw or jawbone is the largest, strongest and lowest bone in the human facial skeleton. It forms the lower jaw and holds the lower teeth in place. The mandible sits beneath the maxilla. It is the only movable bone ...
to inflict a painful bite. Autohaemorrhaging of hemolymph
Hemolymph, or haemolymph, is a fluid, analogous to the blood in vertebrates, that circulates in the interior of the arthropod (invertebrate) body, remaining in direct contact with the animal's tissues. It is composed of a fluid plasma in which ...
, which contains toxic phytotoxin
Phytotoxins are substances that are poisonous or toxic to the growth of plants. Phytotoxic substances may result from human activity, as with herbicides, or they may be produced by plants, by microorganisms, or by naturally occurring chemical react ...
s, is another defensive strategy used by many species of katydids and possibly also the members of genus ''Panoploscelis''. In addition to these adaptations, their massive size and the strength of their heavily armored, thorny legs offers them significant protection.[
]
Relationship with humans
They are sometimes consumed by local indigenous people
Indigenous peoples are culturally distinct ethnic groups whose members are directly descended from the earliest known inhabitants of a particular geographic region and, to some extent, maintain the language and culture of those original people ...
such as the Siona and Secoya
The Secoya (also known as Angotero, Encabellado, Huajoya, Piojé, Siekopai) are an indigenous peoples living in the Ecuadorian and Peruvian Amazon. They speak the Secoya language Pai Coca, which is part of the Western Tucanoan language group. In E ...
people of eastern Ecuador.
References
Further reading
*
*
{{Taxonbar, from=Q7131466
Tettigoniidae genera
Pseudophyllinae