Tenodera aridifolia

Tenodera aridifolia
Adult female
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Mantodea
Family:	Mantidae
Genus:	Tenodera
Species:	T. aridifolia
Binomial name
Tenodera aridifolia (Stoll, 1813)
Subspecies
T. a. aridifolia (Stoll, 1813) T. a. brevicollis (Breier, 1933)

Tenodera aridifolia, the Japanese giant mantis, is a species of mantis in the subfamily Mantinae. The Chinese mantis,^[1] T. sinensis, was once considered to be a subspecies of T. aridifolia, but the species can be distinguished by the shape of male genitalia.^[2]

The Japanese giant mantis is Japan's largest native mantis species.^[3] Adults are large and slender, with long raptorial forelegs and triangular head.^[3] Females are typically between 80-105 mm, and males are typically smaller at 65-85mm.^[3] Colour can vary depending on the habitat, from light green to brown.^[3] A distinctive feature is a yellowish spot on the base of the fore-coxa, and the hind wings are dark brown to purplish when opened which is key trait for determining the difference between Tenodera aridifolia and T. sinensis.^[3]

T. aridifolia is one of the most widespread and abundant temperature mantid species.^[4] They are widely distributed across East Asia.^[5] They are found in Japan, China, Taiwan, Korea and Russia.^[5] In Japan, they are widely distributed throughout Honshu, Shikoku, Kyushu and surrounding islands.^[3]

The Japanese giant mantis thrives in warm, open habitats with abundant prey.^[5] Places such as gardens, cultivated fields, forest edges, shrublands and rice fields with dense vegetation are suitable habitats.^[5] They are common in grasslands in the mainlands of Japan.^[6]

Tenodera aridifolia have different types of mating behaviours, however sexual cannibalism is one of the more well known behaviours within mantids.^[7] In praying mantids, including Tenodera aridifolia, sexual cannibalism occurs 13-28% of the time in natural encounters, which can result in high mortality of males during the breeding season^[8]. Cannibalism depends on body size; both young and old mantids battle with each other, with the winner eating the loser.^[4] Pheromone emission by females might result in multiple mating for females, with males also being able to mate multiple times.^[7] As females can have multiple mates during breeding season, the occurrence of multiple paternity has been observed.^[9] Males can determine mating status of females based on smell. ^[10] Female emitted pheromones are important for long distance attraction of mates.^[7] Visual cues and signals can be important for mate attraction at short distances.^[7] Males detection and location of a female is guided largely by sight, using sight also to help with species identification and provide insight on females phenotype, physiological condition and predatory posturing.^[7]

Like many other temperate mantids, Tenodera aridifolia are univoltine and spend the winter as eggs in egg cases.^[6] Mantid Nymphs suffer high mortality from starvation and cannibalism.^[4] Sporadic patterns of egg hatches in T. aridifolia has been considered to cause diversity in stage structure during the course of nymphal development.^[4] With differences in body size persisting through the development period.^[4]

Tenodera aridifolia as well as other mantid species rely on their cryptic colouration and immobile stance to remain cryptic within dense vegetation, which assists them in ambushing prey and avoiding predation.^[4] Tenodera aridifolia is also an opportunistic generalist predator capturing many kinds of insects, spiders and small invertebrates.^[11] They detect prey mainly through vision and capture it with their raptorial forelimbs.^[11]

Tracking and fixating on prey happens by the moving of the head before striking the prey.^[12] When detecting and analyzing a small moving object such as a prey item, the mantis keeps the image of a target on a foveal region.^[12] This is called visual tracking.^[12] The smooth tracking enables mantids to maintain the position of their targets entirely within the foveal region.^[12]

There are varying preferences for site selection as well as for specific vegetation according to mantid developmental stage.^[4] Later instar mantids prefer leaves with larger area, with early instar mantids preferring small leaves.^[4] Choosing vegetation that is sturdy enough for mantids to pounce efficiently on prey. ^[4] Preference for locations at or near the top of vegetation regardless of developmental stage of the mantid have been observed.^[4] Likely to maximize foraging efficiency and to avoid predation.^[4]

Various defensive responses have been observed in Tenodera aridifolia. The type of response is often dependent on the developmental stage of the mantis.^[11] Small mantids tend to show immobility and cryptic responses for avoiding predators, while larger mantids tend to exhibit deimatic and defensive strike responses for threatening predators.^[11] When it comes to rapidly approaching objects that could be potential dangers such as predators or an impending collision, the looming visual stimuli evokes three kinds of behaviours.^[13] These behaviours being fixation, evasion and cryptic reactions.^[13]

Takydromus tachydromoides, the Japanese grass lizard, can be found in the same environments as T. aridifolia, with both being native to Japan.^[11] Both species are sympatric generalist predators feeding on similar prey.^[11] The interaction between the two is likely an intraguild predation, with Japanese grass lizards eating small T. aridifolia, and large T. aridifolia preying on young Japanese grass lizards.^[11] Both species are found in grasslands and likely compete for similar food resources.^[11]

There are two subspecies:^[14]

• Tenodera aridifolia aridifolia (Stoll, 1813)
• Tenodera aridifolia brevicollis (Breier, 1933)

• 
  Adult male in Taipei, Taiwan
• Video of Tenodera aridifolia in Tokyo, Japan in 2016
• 
  Tenodera aridifolia
• 
  Tenodera aridifolia Female

T. aridifolia on Animal Diversity Web: https://animaldiversity.org/accounts/Tenodera_aridifolia/