Gonodactylus chiragra | |
---|---|
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Arthropoda |
Class: | Malacostraca |
Order: | Stomatopoda |
Family: | Gonodactylidae |
Genus: | Gonodactylus |
Species: | G. chiragra
|
Binomial name | |
Gonodactylus chiragra (
Fabricius, 1781)
| |
Synonyms | |
Squilla chiragra Fabricius, 1781 |
Gonodactylus chiragra is a medium to large mantis shrimp that is distributed widely throughout the West Indo-Pacific.
The synonymy of G. chiragra remains unclear because all members of Gonodactylus have been confused with G. chiragra at some point. [1] This species also displays a large amount of variation, which has made classification even more difficult. [2] Newer research by Manning has resulted in the discovery of several new species that were previously thought to be G. chiragra. [3]
The species typically grows to a maximum length of 105 millimetres and is sexually dimorphic. [4] Males range in color from brown to a dark green, and females from a grey/green to white. [5]
All mantis shrimp (stomatopods) are either spearers or smashers. G. chiragra is a smasher, which means that the heel on their second pair of thoracic appendages is greatly enlarged, forming a club that is used to smash prey. [6] When a target is spotted, G. chiragra strike powerfully and quickly in one of the quickest punches in all of nature. [7] Common targets for eating are snails, hermit crabs, and clams, but bigger animals are sometimes targeted such as mollusks and other crustaceans. [8] G. chiragra are one of the largest smashers and employ a unique fighting strategy in which they circle around the target and aim at the head. [6] This is thought to have developed as a result of intense competition for suitable burrows among stomatopods. [6]
The species is considered one of the most aggressive species of mantis shrimp and when in captivity, routinely strike glass walls and air tubes in the aquarium. [1]
Seeing underwater is very different because in the ambient light there is strong spectral variations that affect color vision. [9] The eyes of G. chiragra are some of the most unique in all of the animal world because they are sensitive to linear polarization. [10] Living underwater, this provides many benefits to them including increased contrast enhancement, ability to see polarization reflecting prey, and better navigation among the light-scattered ocean environment. [10]
The eyes themselves are large stalked apposition compound eyes and have two defining features that affect their complexity. [10] First is their rotational ability; the eyes move completely independent of each other and one eye only is enough for catching prey. [11] Second is the presence of a midband, a large strip of specialized ommatidia (clusters of photoreceptor cells) that divides each eye equally into two segments. [12] The midband contains specialized polarization receptors in rows five and six. In row 2D, photoreceptors have unidirectional microvilli, which makes them sensitive to linear polarized light. [10] The midband is also responsible for binocular distant vision. [11]
Although their eyes are incredibly complex among animals, G. chiragra are one of the few species of mantis shrimp that do not have polarized body markings. [10] This offers them one less form of communication, and it is thought that evolution of deadly weapons (see "Claws" above) was preferred to body signals because of their restricted habitat. [10]
The species is widely distributed in the western Indo-Pacific. [3] It occurs in shallow water in the upper intertidal zone around boulders and coral heads where prey is available. [13] G. chiragra are burrowers, but usually do not construct their own shelters. Instead, they inhibit rocky cavities that are either natural or created by other animals such as mollusks. [1] However, they are equipped to erode the material of the burrow so that it perfectly fits their body shape. [1] Burrows serve many purposes, including protection, lookouts for finding prey, consuming prey, mating, and keeping eggs safe. [1] G. chiragra are active during the day and often close off the entrance to their shelter at night using bits of sand and rocks. [8]
{{
cite journal}}
: CS1 maint: multiple names: authors list (
link)
{{
cite journal}}
: CS1 maint: multiple names: authors list (
link)
{{
cite journal}}
: CS1 maint: multiple names: authors list (
link)
Gonodactylus chiragra | |
---|---|
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Arthropoda |
Class: | Malacostraca |
Order: | Stomatopoda |
Family: | Gonodactylidae |
Genus: | Gonodactylus |
Species: | G. chiragra
|
Binomial name | |
Gonodactylus chiragra (
Fabricius, 1781)
| |
Synonyms | |
Squilla chiragra Fabricius, 1781 |
Gonodactylus chiragra is a medium to large mantis shrimp that is distributed widely throughout the West Indo-Pacific.
The synonymy of G. chiragra remains unclear because all members of Gonodactylus have been confused with G. chiragra at some point. [1] This species also displays a large amount of variation, which has made classification even more difficult. [2] Newer research by Manning has resulted in the discovery of several new species that were previously thought to be G. chiragra. [3]
The species typically grows to a maximum length of 105 millimetres and is sexually dimorphic. [4] Males range in color from brown to a dark green, and females from a grey/green to white. [5]
All mantis shrimp (stomatopods) are either spearers or smashers. G. chiragra is a smasher, which means that the heel on their second pair of thoracic appendages is greatly enlarged, forming a club that is used to smash prey. [6] When a target is spotted, G. chiragra strike powerfully and quickly in one of the quickest punches in all of nature. [7] Common targets for eating are snails, hermit crabs, and clams, but bigger animals are sometimes targeted such as mollusks and other crustaceans. [8] G. chiragra are one of the largest smashers and employ a unique fighting strategy in which they circle around the target and aim at the head. [6] This is thought to have developed as a result of intense competition for suitable burrows among stomatopods. [6]
The species is considered one of the most aggressive species of mantis shrimp and when in captivity, routinely strike glass walls and air tubes in the aquarium. [1]
Seeing underwater is very different because in the ambient light there is strong spectral variations that affect color vision. [9] The eyes of G. chiragra are some of the most unique in all of the animal world because they are sensitive to linear polarization. [10] Living underwater, this provides many benefits to them including increased contrast enhancement, ability to see polarization reflecting prey, and better navigation among the light-scattered ocean environment. [10]
The eyes themselves are large stalked apposition compound eyes and have two defining features that affect their complexity. [10] First is their rotational ability; the eyes move completely independent of each other and one eye only is enough for catching prey. [11] Second is the presence of a midband, a large strip of specialized ommatidia (clusters of photoreceptor cells) that divides each eye equally into two segments. [12] The midband contains specialized polarization receptors in rows five and six. In row 2D, photoreceptors have unidirectional microvilli, which makes them sensitive to linear polarized light. [10] The midband is also responsible for binocular distant vision. [11]
Although their eyes are incredibly complex among animals, G. chiragra are one of the few species of mantis shrimp that do not have polarized body markings. [10] This offers them one less form of communication, and it is thought that evolution of deadly weapons (see "Claws" above) was preferred to body signals because of their restricted habitat. [10]
The species is widely distributed in the western Indo-Pacific. [3] It occurs in shallow water in the upper intertidal zone around boulders and coral heads where prey is available. [13] G. chiragra are burrowers, but usually do not construct their own shelters. Instead, they inhibit rocky cavities that are either natural or created by other animals such as mollusks. [1] However, they are equipped to erode the material of the burrow so that it perfectly fits their body shape. [1] Burrows serve many purposes, including protection, lookouts for finding prey, consuming prey, mating, and keeping eggs safe. [1] G. chiragra are active during the day and often close off the entrance to their shelter at night using bits of sand and rocks. [8]
{{
cite journal}}
: CS1 maint: multiple names: authors list (
link)
{{
cite journal}}
: CS1 maint: multiple names: authors list (
link)
{{
cite journal}}
: CS1 maint: multiple names: authors list (
link)