Chaetodon lunula
(raccoon butterflyfish)
Marine Fishes
Exotic |
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Common name: raccoon butterflyfish
Synonyms and Other Names: Pomacentrus lunula (original combination); raccoon butterfly
Taxonomy: available through
www.itis.gov
Identification: Family Chaetodontidae
Members of the Family Chaetodontidae (i.e., butterflyfishes) typically are oval-shaped, deep-bodied and highly compressed. Chaetodontids have a single, continuous dorsal fin and a scaly axillary process at the upper base of the pelvic fins. Many chaetodontids are brightly coloured and thus popular aquarium fishes. Most species have a dark vertical bar across the head that obscures the eye and a dark "false eye" on the posterior portion of the body. The combination of the eyebar and false eye confuses potential predators about the identity and/or orientation of the fish (Neudecker 1989).
Butterflyfishes are probably most similar in appearance to angelfishes (family Pomacanthidae), but can easily be distinguished from them. Butterflyfishes lack the distinctive spine(s) at the angle of the preopercle in angelfishes. Also, angelfishes lack the scaly axillary process at the base of the pectoral fins and false-eye spots.
Chaetodon lunula
The lateral line is complete with < 60 scales. The pectoral fins are rounded, not elongated. The snout is only slightly pronounced and the head profile is steep. Dorsal fin XI-XIII (22-25), anal fin III (17-19). Pectoral rays 15 or 16.
Most chaetodontids are identified by their distinctive colour patterns (see photo above). The body is primarily yellow with some brownish markings. The vertical ocular bar is black; posterior to the ocular bar is a broad, white bar. These two bars together give the appearance of a raccoon's mask. Large black and brown markings occur on the upper dorsum posterior to the white bar and dorsally to the base of the dorsal fin. There is a black blotch at the caudal peduncle. The dorsal, caudal and anal fins are edged in black. Juveniles have a black blotch at the posterior base of the caudal fin.
Chaetodon fasciatus (Red Sea raccoon butterflyfish) is a similar species from the Red Sea. In Florida, a similar species is the reef butterflyfish (Chaetodon sedentarius), which lacks white markings on head and wide dark wedge on rear dorsal and body.
Summarised from Pyle (2001); Allen et al. (2003), Randall (2005); illustrated in Burgess and Axelrod (1973); Myers (1999).
Size: to 20 cm TL
Native Range: The species is native to most of the Indo-Pacific, including East and South Africa, Hawai’i, southern Japan, Western Australia and throughout Micronesia. It also occurs around the Cape of Good Hope reaching narrowly into the South-eastern Atlantic along the South African coast. It is absent from the Red Sea, Gulf of Aden, Persian Gulf, and Arabian Sea. In the eastern Pacific, single individuals have been seen at Cocos Island and the Galápagos Islands. From Randall et al. (1996), Pyle (2001), Robertson et al. (2004), and Randall (2005).
Nonindigenous Occurrences:
In Florida, this species has been observed/photographed on reefs off Boca Raton (in 2000 [Semmens et al. 2004] in 2001 and 2002 [REEF 2008]), Deerfield Beach (in 2004 [REEF 2008]) and Delray Beach (in 2008 [L. Akins, pers. comm.]). A single individual was observed in each sighting.
Table 1. States with nonindigenous occurrences, the earliest and latest observations in each state, and the tally and names of HUCs with observations†. Names and dates are hyperlinked to their relevant specimen records. The list of references for all nonindigenous occurrences of Chaetodon lunula are found here.
Table last updated 4/19/2024
† Populations may not be currently present.
Ecology: There are 40 or more species of butterflyfishes in the Indo-Pacific and they exhibit varying degrees of habitat specificity. For the raccoon butterflyfish, the typical habitat includes coral reefs from one to 60 m in depth (Pyle 2001). In Moorea (French Polynesia), the raccoon butterflyfish was found to be ubiquitous and distributed regularly across the reef, including the fringing reef and the deeper outer slope (Bouchon-Navaro 1981). The raccoon butterflyfish is an omnivore and may occur as single individuals, pairs or small groups (Hourigan 1989). Raccoon butterflies in Moorea ate a variety of benthic prey, including polychaetes, scleractinians (hard corals), hydroids, gastropods and mollusc eggs (Harmelin-Vivien 1989). Like many reef fishes, butterflyfishes spawn their pelagic eggs into the water column where they are fertilized and dispersed by the currents (Hourigan 1989). Eggs are small (<1 mm) and embryos hatch about 30 hours after fertilization (Leis 1989). The larvae subsequently spend about 40 days in the plankton before settling to the reef (Hourigan and Reese 1987). Age estimates for the duration of the pelagic phase (based on otoliths) varied from 20 to 57 days for 23 chaetodontid fishes in a study by Leis (1989). The duration of the pelagic stage is unknown specifically for the raccoon butterflyfish. However, Watanabe (1946 in Leis 1989) documented that larvae measured <15.5 mm at settlement.
Means of Introduction: Probable aquarium release.
Status: Reported from Florida.
Impact of Introduction: The impacts of this species are currently unknown, as no studies have been done to determine how it has affected ecosystems in the invaded range. The absence of data does not equate to lack of effects. It does, however, mean that research is required to evaluate effects before conclusions can be made.
References: (click for full references)
Allen, G., R. Steene, P. Humann and N. Deloach. 2003. Reef Fish Identification. Tropical Pacific. New World Publications, Inc., Jacksonville, Florida and Odyssey Publications, El Cajon, California.
Bouchon-Navaro, Y. 1981. Quantitative distribution of the Chaetodontidae on a reef of Moorea Island (French Polynesia). Journal of Experimental Marine Biology and Ecology 55: 145-157.
Burgess, W. and H. R. Axelrod. 1973. Pacific Marine Fishes. Book 1. T. F. H. Publications, Ltd.
Harmelin-Vivien, M. L. 1989. Implications of feeding specialization on the recruitment processes and community structure of butterflyfishes. Environmental Biology of Fishes 25: 101-110.
Hourigan, T. F. 1989. Environmental determinants of butterflyfish social systems. Environmental Biology of Fishes 25: 61-78.
Leis, J. M. 1989. Larval biology of butterflyfishes (Pisces, Chaetodontidae): what do we really know? Environmental Biology of Fishes 25: 87-100.
Myers, R. F. 1999. Micronesian Reef Fishes. A field guide for divers and aquarists. Coral Graphics, Davie, FL.
Neudecker, S. 1989. Eye camouflage and false eyespots: chaetodontid responses to predators. Environmental Biology of Fishes 25: 143-157.
Pyle, R. 2001. Chaetodontidae. Butterflyfishes. Pages 3224-3265 In: Carpenter, K. E. and V. H. Niem, (Eds.). FAO species identification guide for fishery purposes. The living marine resources of the Western Central Pacific. Volume 5. Bony fishes part 3 (Menidae to Pomacentridae).
Randall, J. E. 2005. Reef and Shore Fishes of the South Pacific. New Caledonia to Tahiti and the Pitcairn Islands. University of Hawai’i Press, Honolulu.
Reef Environmental Education Foundation (REEF). 2008. Exotic species sighting program and volunteer database. World wide web electronic publication. www.reef.org, date of download March 10, 2008.
Semmens, B. X., E. R. Buhle, A. K. Salomon and C. V. Pattengill-Semmens. 2004. A hotspot of non-native marine fishes: evidence for the aquarium trade as an invasion pathway. Marine Ecology Progress Series 266: 239-244.
Other Resources:
FishBase Summary
Author:
Schofield, P.J.
Revision Date: 3/22/2021
Peer Review Date: 9/19/2011
Citation Information:
Schofield, P.J., 2024, Chaetodon lunula (Lacepède, 1802): U.S. Geological Survey, Nonindigenous Aquatic Species Database, Gainesville, FL, https://nas.er.usgs.gov/queries/FactSheet.aspx?speciesID=2301, Revision Date: 3/22/2021, Peer Review Date: 9/19/2011, Access Date: 4/19/2024
This information is preliminary or provisional and is subject to revision. It is being provided to meet the need for timely best science. The information has not received final approval by the U.S. Geological Survey (USGS) and is provided on the condition that neither the USGS nor the U.S. Government shall be held liable for any damages resulting from the authorized or unauthorized use of the information.
