Galearctus avulsus
Encyclopedia
Galearctus avulsus is a species of slipper lobster
that lives around New Caledonia
. It was described in 2011, having previously been included in Galearctus kitanovirosus. It differs from the other species of the genus Galearctus
most noticeably in the shape of a groove on the sternum.
around 16–32 mm (0.62992125984252–1.3 ) long, including the rostrum
. It differs from the other species in the genus Galearctus
by the shape of the groove on the midline of the sternum between the first pair of pereiopods. In the other species, this groove is narrow, but in G. avulsus, it widens and appears as if "torn away".
and the Chesterfield Islands
, at depths of 230–680 m (754.6–2,231 ). It may also occur around Fiji
. Although G. avulsus is very poorly known, it has a large range
and no apparent threats, and is therefore listed as being of Least Concern
on the IUCN Red List
.
, Korea
and Taiwan
. In 2002, Lipke Holthuis
revised the Indo-Pacific
slipper lobsters, erecting a new genus, Galearctus
for "S. kitanoviriosus" and its nearest relatives. At the same time, Holthuis added records of G. kitanoviriosus from deeper waters in the South Pacific. Re-examination of the specimens from the two parts of the range by Chien-Hui Yang, I-Shiung Chen and Tin-Yam Chan from National Taiwan Ocean University
revealed constant differences between the two groups. Since the type material of G. kitanoviriosus was from the northern part of the range, they described the southern populations as a new species, G. avulsus; the specific epithet meaning "torn away", in reference to the shape of the median groove on the first thoracic sternite. DNA sequencing
of the cytochrome oxidase I gene suggests that the nearest relative of G. avulsus is not G. kitanoviriosus but G. rapanus.
Slipper lobster
Slipper lobsters are a family of decapod crustaceans found in all warm oceans and seas. Despite their name, they are not true lobsters, but are more closely related to spiny lobsters and furry lobsters. Slipper lobsters are instantly recognisable by their enlarged antennae, which project forward...
that lives around New Caledonia
New Caledonia
New Caledonia is a special collectivity of France located in the southwest Pacific Ocean, east of Australia and about from Metropolitan France. The archipelago, part of the Melanesia subregion, includes the main island of Grande Terre, the Loyalty Islands, the Belep archipelago, the Isle of...
. It was described in 2011, having previously been included in Galearctus kitanovirosus. It differs from the other species of the genus Galearctus
Galearctus
Galearctus is a genus of slipper lobsters, comprising the following species:*Galearctus aurora *Galearctus avulsus Yang, Chen & Chan, 2011*Galearctus kitanoviriosus *Galearctus rapanus...
most noticeably in the shape of a groove on the sternum.
Description
Galearctus avulsus is a small slipper lobster, with a carapaceCarapace
A carapace is a dorsal section of the exoskeleton or shell in a number of animal groups, including arthropods such as crustaceans and arachnids, as well as vertebrates such as turtles and tortoises. In turtles and tortoises, the underside is called the plastron.-Crustaceans:In crustaceans, the...
around 16–32 mm (0.62992125984252–1.3 ) long, including the rostrum
Rostrum (anatomy)
The term rostrum is used for a number of unrelated structures in different groups of animals:*In crustaceans, the rostrum is the forward extension of the carapace in front of the eyes....
. It differs from the other species in the genus Galearctus
Galearctus
Galearctus is a genus of slipper lobsters, comprising the following species:*Galearctus aurora *Galearctus avulsus Yang, Chen & Chan, 2011*Galearctus kitanoviriosus *Galearctus rapanus...
by the shape of the groove on the midline of the sternum between the first pair of pereiopods. In the other species, this groove is narrow, but in G. avulsus, it widens and appears as if "torn away".
Distribution and conservation
Galearctus avulsus lives in the waters around New CaledoniaNew Caledonia
New Caledonia is a special collectivity of France located in the southwest Pacific Ocean, east of Australia and about from Metropolitan France. The archipelago, part of the Melanesia subregion, includes the main island of Grande Terre, the Loyalty Islands, the Belep archipelago, the Isle of...
and the Chesterfield Islands
Chesterfield Islands
Chesterfield Islands is a french archipelago of New Caledonia located in the Coral Sea, 550 km northwest of Grande Terre the main island of New Caledonia. Chesterfield Islands are a 120 km long and 70 km broad structure composed with 11 islets and many reefs...
, at depths of 230–680 m (754.6–2,231 ). It may also occur around Fiji
Fiji
Fiji , officially the Republic of Fiji , is an island nation in Melanesia in the South Pacific Ocean about northeast of New Zealand's North Island...
. Although G. avulsus is very poorly known, it has a large range
Range (biology)
In biology, the range or distribution of a species is the geographical area within which that species can be found. Within that range, dispersion is variation in local density.The term is often qualified:...
and no apparent threats, and is therefore listed as being of Least Concern
Least Concern
Least Concern is an IUCN category assigned to extant taxon or lower taxa which have been evaluated but do not qualify for any other category. As such they do not qualify as threatened, Near Threatened, or Conservation Dependent...
on the IUCN Red List
IUCN Red List
The IUCN Red List of Threatened Species , founded in 1963, is the world's most comprehensive inventory of the global conservation status of biological species. The International Union for Conservation of Nature is the world's main authority on the conservation status of species...
.
Taxonomic history
In 1962, Harada described a new species of slipper lobster, "Scyllarus kitanoviriosus" from shallow water (less than 100 m or 328.1 ft deep) around JapanJapan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
, Korea
Korea
Korea ) is an East Asian geographic region that is currently divided into two separate sovereign states — North Korea and South Korea. Located on the Korean Peninsula, Korea is bordered by the People's Republic of China to the northwest, Russia to the northeast, and is separated from Japan to the...
and Taiwan
Taiwan
Taiwan , also known, especially in the past, as Formosa , is the largest island of the same-named island group of East Asia in the western Pacific Ocean and located off the southeastern coast of mainland China. The island forms over 99% of the current territory of the Republic of China following...
. In 2002, Lipke Holthuis
Lipke Holthuis
Lipke Bijdeley Holthuis was a Dutch carcinologist, considered one of the "undisputed greats" of carcinology, and "the greatest carcinologist of our time"....
revised the Indo-Pacific
Indo-Pacific
The Indo-Pacific is a biogeographic region of the Earth's seas, comprising the tropical waters of the Indian Ocean, the western and central Pacific Ocean, and the seas connecting the two in the general area of Indonesia...
slipper lobsters, erecting a new genus, Galearctus
Galearctus
Galearctus is a genus of slipper lobsters, comprising the following species:*Galearctus aurora *Galearctus avulsus Yang, Chen & Chan, 2011*Galearctus kitanoviriosus *Galearctus rapanus...
for "S. kitanoviriosus" and its nearest relatives. At the same time, Holthuis added records of G. kitanoviriosus from deeper waters in the South Pacific. Re-examination of the specimens from the two parts of the range by Chien-Hui Yang, I-Shiung Chen and Tin-Yam Chan from National Taiwan Ocean University
National Taiwan Ocean University
|name = National Taiwan Ocean University|native_name = 國立臺灣海洋大學|image =|motto = Honest, Simple, Erudite, Perseverance|established = 1953|type = Public|president = Kuo-Tien Lee|city = Keelung...
revealed constant differences between the two groups. Since the type material of G. kitanoviriosus was from the northern part of the range, they described the southern populations as a new species, G. avulsus; the specific epithet meaning "torn away", in reference to the shape of the median groove on the first thoracic sternite. DNA sequencing
DNA sequencing
DNA sequencing includes several methods and technologies that are used for determining the order of the nucleotide bases—adenine, guanine, cytosine, and thymine—in a molecule of DNA....
of the cytochrome oxidase I gene suggests that the nearest relative of G. avulsus is not G. kitanoviriosus but G. rapanus.