Karstarma is a genus

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of karst

KARST

Kilometer-square Area Radio Synthesis Telescope is a Chinese telescope project to which FAST is a forerunner. KARST is a set of large spherical reflectors on karst landforms, which are bowlshaped limestone sinkholes named after the Kras region in Slovenia and Northern Italy. It will consist of...

-dwelling crab

Crab

True crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting "tail" , or where the reduced abdomen is entirely hidden under the thorax...

s formerly included in Sesarmoides.

Description

Karstarma is distinguished from the closely related Sesarmoides by the lack of a stridulatory

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 fishes, snakes and spiders...

 structure on the cheliped which is present in the latter genus.

Ecology & biogeography

All species in the genus Karstarma are typically found in anchialine pool

Anchialine pool

An anchialine pool or pond is a landlocked body with a subterranean connection to the ocean. Anchialine pools are a feature of coastal aquifers which are density stratified, with the water near the surface being fresh or brackish, and saline water intruding from the coast below at some depth...

s across the West Pacific.

Taxonomy

The genus name Karstarma is derived from the word karst, in arbitrary combination with the genus name Sesarma

Sesarma

Sesarma is a genus of terrestrial crabs. Many species within this genus live in mangroves. They have evolved to be fully terrestrial, which means they do not have to return to the sea even to spawn...

. It has been frequently misspelt Karstama, including in the original description.

In the original description of the genus, 12 species were included. Three species have since been added.

• Karstarma ardea Wowor & Ng, 2009
• Karstarma balicum (Ng, 2002)
• Karstarma boholano (Ng, 2002)
• Karstarma cerberus (Holthuis, 1946)
• Karstarma emdi (Ng & Whitten, 1995)
• Karstarma guamense (Ng, 2002)
• Karstarma jacksoni (Balss, 1934)
• Karstarma jacobsoni (Ihle, 1912)
• Karstarma loyalty (Ng, 2002)
• Karstarma microphthalmus (Naruse & Ng, 2007)
• Karstarma novabritannia (Ng, 1988)
• Karstarma philippinarum Husana et al., 2010
• Karstarma sulu (Ng, 2002)
• Karstarma ultrapes (Ng, Guinot & Iliffe, 1994)
• Karstarma waigeo Wowor & Ng, 2009