''Chaetodon ulietensis'', the Pacific double-saddle butterflyfish or false falcula butterflyfish, is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

butterflyfish The butterflyfish are a group of conspicuous tropical marine fish of the family Chaetodontidae; the bannerfish and coralfish are also included in this group. The approximately 129 species in 12 genera are found mostly on the reefs of the Atla ...

(

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Chaetodontidae). It flourishes in

coral Corals are marine invertebrates within the class Anthozoa of the phylum Cnidaria. They typically form compact colonies of many identical individual polyps. Coral species include the important reef builders that inhabit tropical oceans and ...

-rich environments in the central Indo-Pacific region. Their range extends from the

Cocos-Keeling Islands ) , anthem = "''Advance Australia Fair''" , song_type = , song = , image_map = Australia on the globe (Cocos (Keeling) Islands special) (Southeast Asia centered).svg , map_alt = Location of the Cocos (Keeling) Islands , map_caption = ...

to the

Tuamotu Islands The Tuamotu Archipelago or the Tuamotu Islands (french: Îles Tuamotu, officially ) are a French Polynesian chain of just under 80 islands and atolls in the southern Pacific Ocean. They constitute the largest chain of atolls in the world, extendin ...

, and north to Japan. They are usually found from the surface to 20 m depths, and like shallow channels with high current.

Description and systematics

These fish can reach a size of . They are white with vertical thin black lines down the body and two dark saddles on the fore and hind back, which softly grade into the background colour caudal gradient. Immediately after the hind quarter saddle, the body and tail is bright yellow swith a black spot on the

caudal peduncle Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as see ...

. The

dorsal fin A dorsal fin is a fin located on the back of most marine and freshwater vertebrates within various taxa of the animal kingdom. Many species of animals possessing dorsal fins are not particularly closely related to each other, though through c ...

has a streak of yellow from the crown of the head to the tail. Like most of its relatives, this species displays a black eye band like a mask. As in most butterflyfish, the Pacific double-saddle butterflyfish is prone to blanching at night and when startled. It belongs to the large subgenus ''Rabdophorus'' which might warrant recognition as a distinct

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

. In this group, the closest relative of this particular species is the similar-looking black-wedged butterflyfish, ''C. falcula''. Other fairly close relatives are the quite differently-shaped but similarly-coloured lined (''C. lineolatus'') and spot-naped butterflyfishes (''C. oxycephalus''), while the

blue-cheeked butterflyfish The blue-cheeked butterflyfish (''Chaetodon semilarvatus'') is a species of marine ray-finned fish, a butterflyfish belonging to the family Chaetodontidae. It is found in the northwestern Indian Ocean. Description The bluecheek butterflyfish h ...

(''C. semilarvatus'') seems to be a far more basal lineage relative to all of these. The vertical lines are present in all of these, while a white body with yellow behind and black on back and

are only shared among the four less ancient species.

Ecology

''Chaetodon ulietensis'' is often found singly or in pairs on coral-rich

reef A reef is a ridge or shoal of rock, coral or similar relatively stable material, lying beneath the surface of a natural body of water. Many reefs result from natural, abiotic processes— deposition of sand, wave erosion planing down rock o ...

systems, foraging on

sessile Sessility, or sessile, may refer to: * Sessility (motility), organisms which are not able to move about * Sessility (botany), flowers or leaves that grow directly from the stem or peduncle of a plant * Sessility (medicine), tumors and polyps that ...

invertebrate Invertebrates are a paraphyletic group of animals that neither possess nor develop a vertebral column (commonly known as a ''backbone'' or ''spine''), derived from the notochord. This is a grouping including all animals apart from the chordate ...

s and

alga Algae (; singular alga ) is an informal term for a large and diverse group of photosynthetic eukaryotic organisms. It is a polyphyletic grouping that includes species from multiple distinct clades. Included organisms range from unicellular mic ...

e. It is not a territorial species that freely grazes throughout a wide range within reefs,

lagoon A lagoon is a shallow body of water separated from a larger body of water by a narrow landform, such as reefs, barrier islands, barrier peninsulas, or isthmuses. Lagoons are commonly divided into ''coastal lagoons'' (or ''barrier lagoons'') ...

s and harbors, and every now and then large groups congregate at rich feeding spots. It is rarely ever observed in a deep reef environment or the open sea; juveniles are typically reared in shallow lagoons,

estuaries An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environmen ...

or harbors. An opportunistic omnivore, diet consists mainly of microscopic

e, other

plankton Plankton are the diverse collection of organisms found in water (or air) that are unable to propel themselves against a current (or wind). The individual organisms constituting plankton are called plankters. In the ocean, they provide a crucia ...

, and small sessile

s. As a measure of defense, they typically wedge themselves in tight crevasses to escape

predator 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 ...

In the aquarium

Although common in the wild, it is rarely imported by the aquarium trade. In aquarist terms, it is considered a hardy '' Chaetodon'' and beneficial for the control of nuisance pests. The Pacific Double-saddle Butterflyfish has been observed as a beneficial

of ''

Aiptasia ''Aiptasia'' is a genus of a symbiotic cnidarian belonging to the class Anthozoa ( sea anemones, corals). ''Aiptasia'' is a widely distributed genus of temperate and tropical sea anemones of benthic lifestyle typically found living on mangrov ...

'' and ''

Majano Majano ( fur, Maian) is a ''comune'' (municipality) in the Italian region of Friuli-Venezia Giulia, located about northwest of Trieste and about northwest of Udine. Majano borders the following municipalities: Buja, Colloredo di Monte Albano ...

'' sea anemones. Like most Raccoon Butterflyfish (''C. lunula''), ''C. ulietensis'' will eliminate this nuisance within a 2- to 6-week period depending on the anemone population and size of the tank. And unlike most raccoon butterflyfish, this species rarely feeds on ornamental corals. The Pacific Double-saddle Butterflyfish readily accepts most prepared frozen and dry foods, thus it can easily make the transition to aquarium life, unlike the

Copperband Butterflyfish The copperband butterflyfish (''Chelmon rostratus''), also known as the beaked coral fish, is found in reefs in both the Pacific and Indian Oceans. This butterflyfish is one of the three species that make up the genus ''Chelmon'' and all have lon ...

(''Chelmon rostratus'') or other less hardy ''Chaetodon'' species.

Footnotes

References

* (2007): Molecular phylogenetics of the butterflyfishes (Chaetodontidae): Taxonomy and biogeography of a global coral reef fish family. '' Mol. Phylogenet. Evol.'' 45(1): 50–68. (HTML abstract) * (2008)
''Chaetodon ulietensis''
Version of 2008-JUL-24. Retrieved 2008-SEP-01. * (2007): Molecular phylogeny of ''Chaetodon'' (Teleostei: Chaetodontidae) in the Indo-West Pacific: evolution in geminate species pairs and species groups. ''Raffles Bulletin of Zoology Supplement'' 14: 77-86
PDF fulltext

External links

* {{Taxonbar, from=Q2697327 ulietensis Fish described in 1831 Taxa named by Georges Cuvier