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Tapinoma melanocephalum (Fabricius), a new exotic pest in Korea
Journal of Asia-Pacific Entomology 12 (2009) 67–69
Contents lists available at ScienceDirect
Journal of Asia-Pacific Entomology j o u r n a l h o m e p a g e : w w w. e l s ev i e r. c o m / l o c a t e / j a p e
Tapinoma melanocephalum (Fabricius), a new exotic pest in Korea Hyon Chong Choe a,⁎, Jong Ok Lim b, Seunghwan Lee b a
106th Medical Detachment (Veterinary Service), United States Forces Korea, Yongsan Garrison, APO AP 96205, Seoul, Republic of Korea Entomology Program, Department of Agricultural Biotechnology and Research Institute for Agriculture and Life Science, Seoul National University, San 56-1, Sillim-dong, Gwanak-gu, Seoul, Republic of Korea
b
a r t i c l e
i n f o
Article history: Received 24 July 2008 Revised 8 December 2008 Accepted 11 December 2008 Keywords: Tapinoma Melanocephalum Exotic species Establishment Korea
a b s t r a c t Tapinoma melanocephalum (Fabricius) is established as a house pest in various regions of the world, not limited to its original climate zones. T. melanocephalum seems likely to become established in Korea as well, based on our observations of the species from a private house in Seoul, Korea, its history of establishment in the world, and a few unofficial records in Korea. Diagnosis of the species is provided with pictures of specimens. Morphological characteristics identifying T. melanocephalum from the Korean indigenous Tapinoma species are provided. © Korean Society of Applied Entomology, Taiwan Entomological Society and Malaysian Plant Protection Society, 2008 Published by Elsevier B.V. All rights reserved.
Introduction Tapinoma melanocephalum (Fabricius) is one of the most common house pest ants in the world. The ant lives in human dwellings and feeds on various household foods. They have a preference for sweet food and have been observed feeding on sugar, cake, and syrup (Smith, 1965). Indoor nests are usually in small spaces such as cracks, spaces between books, or wall voids. Foragers are found on kitchen sinks, counters, and floors. They can nest outside as well. Outside nests are usually in disturbed areas, such as in flowerpots, under objects on the ground, under loose bark, or at the bases of palm fronds. Outside, the workers scavenge for dead insects and tend sapsucking insects to collect honeydew (Nickerson and Bloomcamp, 2006). Until the 1970s, distribution of T. melanocephalum was limited to tropical and subtropical regions. They are common pests in Florida, Hawaii, and a few tropical islands (Nickerson and Bloomcamp, 2006). T. melanocephalum has been introduced or has become established in other regions of the world through commerce. Its distribution has expanded to temperate latitudes where they can overwinter inside of human dwellings with heated conditions, such as greenhouses and buildings. They have been reported as far north as the northern Nearctic regions, in Ontario, Winnipeg, and Monitoba in Canada. They have recently been reported as introduced or established in Germany (Steinbrink, 1987), Japan (Terayama and Okutani, 1992), the United Arab Emirates (Colling⁎ Corresponding author. Fax: +82 2 7918 5104. E-mail address: [email protected] (H.C. Choe).
wood et al., 1997), Australia (Andersen, 2000), and Finland (Sorvari, 2002). They move quickly and erratically when they are disturbed. Sometimes they show trailing movements, which are much slower and deliberate (Nickerson and Bloomcamp, 2006). The common name “ghost ant” is because of their fast moving behavior. The authors confirm T. melanocephalum for the first time in Korea. In this paper, diagnosis of T. melanocephalum is provided with pictures and specimen records. Morphological characteristics to differentiate T. melanocephalum from the indigenous Tapinoma species in Korea are provided. The status of risk of establishment is briefly discussed. It concluded that the ant seems at a risk of establishment, based on the authors' findings of the species from Seoul, its history of establishments in the world, and previous records in Korea. Materials and methods Specimens were collected by Mr. Yun Chan Song and provided to the authors. According to him, many individuals were observed in his private house from December 2007 to August 2008. The house is located in the eastern area of Seoul (Amsa-dong, Gangdong-gu). The ants disappeared from his house in June and July. The ants moved very fast and arbitrarily, and they were strongly attracted to pet foods. Specimens were identified with a guidance of taxonomic information and terms of Smith's (1991) and Bolton's (1994). A stereoscopic microscope (Leica, BE/S8APO) and a digital camera system (Diagnostic Instrument Inc., 14.2 Color Mosaic) were used for examination
1226-8615/$ – see front matter © Korean Society of Applied Entomology, Taiwan Entomological Society and Malaysian Plant Protection Society, 2008 Published by Elsevier B.V. All rights reserved. doi:10.1016/j.aspen.2008.12.003
68
H.C. Choe et al. / Journal of Asia-Pacific Entomology 12 (2009) 67–69
of the specimens. Identification was confirmed by Dr. Mamoru Terayama (Laboratory of Applied Entomology, University of Tokyo) and specimens are deposited in the Insect Museum of Seoul National University, Seoul, Korea.
Discussion
Taxonomic accounts
Three Tapinoma species have been reported in the Korean peninsula: T. geei Wheeler 1927, T. sinense Wheeler 1925 and T. wroughtoni Forel 1904. They have only been recorded from North Korea thus far (Terayama et al., 1992; Kim and Kim, 1999). Tapinoma melanocephalum (F.) is differentiated from the native Korean Tapinoma species by color patterns and a few morphological characteristics. T. melanocephalum is distinctively bicolored, while the native species are wholly dark. T. melanocephalum does not have a notch on the clypeus, but T. geei has a distinctive notch on clypeus (Fig. 1B). T. melanocephalum can be distinguished from T. sinense and T. wroughtoni by the relative lengths of antennal scapes. Scapes of T. sinense are longest, surpassing the occipital border by one-fourth of the length. Scapes of T. melanocephalum are shorter than those of T. sinense, only slightly overreaching the occipital border. In T. wroughtoni, scapes scarcely overreach the occiput (Collingwood, 1976; Wheeler, 1927 and 1928). Monomorium pharonis (Linnaeus) is a native ant species in Korea, which can be confused with T. melanocephalum. Both species are small and are bicolored. Identification of the two species requires microscopic examinations. The color patterns are slightly different. In T. melanocephalum, the gaster is wholly pale. In M. pharonis, only the first segments are pale and the remaining gastral segments are brown or dark. The two species belong to different subfamilies. T. melanocephalum has a clear promesonotal suture, as a typical species in the subfamily Dolichoderinae. M. pharonis has indistinct promesonotal suture and carries a constriction between third and fourth abdominal segments, as a typical species of the subfamily Myrmecinae (Choi, 1987; Bolton, 1994) (Figs. 1C, D).
Family Formicidae Subfamily Dolichoderinae Tapinoma melanocephalum (Fabricius) Diagnosis. [Worker] Body 1.3–1.8 mm long. Body is bicolored. Head is brown to dark brown. Antennae, mandible and maxillary appendages are pale brownish to yellowish white, or opaque. Mandibles have smooth margins. Alitrunk is dark brown as heads or sometimes a little paler than heads. Gaster and legs are opaque, yellowish or white. Antennae are long, and the scapes surpass the occiput slightly (Fig. 1A). Specimens examined. 10 workers. Amsa-dong, Gangdong-gu, Seoul, Korea. Yun Chan Song.
Morphological differences of T. menalocephalum from the Korean indigenous Tapinoma species and Monomorium pharonis (L.)
Risk of establishment in Korea Tapinoma melanocephalum seems likely to become established in Korea, based on the authors' observation of its survival for several months in Korea and its history of establishment worldwide. The origin of T. melanocephalum is assumed to be tropical and subtropical (Wheeler, 1910), but it has been introduced and established in various regions not limited to their original climate zones. T. melanocephalum survived in various regions of temperate latitudes by nesting inside heated human dwellings. Since 2005, T. melanocephalum has been unofficially recorded in Korea. Most records were apparently based on information from an entomologist's article, describing the introduction of the ghost ant in Korea and its potential risk as a pest if they become established (Kim, 2005). The identifications on the records were based on body size and color and movement patterns. They were published online and without confirmation of collection localities and dates, or examination of morphological characters. Many of the records are assumed to be correct, because T. melanocephalum is easily distinguishable by its erratic movements, body size and color pattern. Previous unofficial records support the authors' assumption that T. melanocephalum has been introduced to Korea and will likely become established. Acknowledgments
Fig. 1. Tapinoma melanocephalum (Fabricius) worker: A, whole body; B, head; C, D, alitrunk (C — dorsal view, D — lateral view).
The authors cordially thank Mr. Yun Chan Song, who collected the samples and provided them with information. Our gratitude is extended to Dr. Mamoru Terayama (Laboratory of Applied Entomology, University of Tokyo) for his confirmation of identification.
H.C. Choe et al. / Journal of Asia-Pacific Entomology 12 (2009) 67–69
References Andersen, A.N., 2000. Ants of Northern Australia: A Guide to the Monsoonal Fauna. CSIRO Publishing, p. 106. Bolton, B., 1994. Identification Guide to the Ant Genera of the World. Harvard University Press, p. 222. Choi, B.M., 1987. Taxonomic study on ants (Formicidae) (1) — on the genus Monomorium. Chongju National University of Education. Sci. Math. Educ. Publ. 11, 17–30 [In Korean]. Collingwood, C.A., 1976. Ants (Hymenoptera, Formicidae) from North Korea. Ann. Hist-nat. Mus. Nat. Hung. 68, 298–309. Collingwood, C.A., Tigar, B.J., Agosti, D., 1997. Introduced ants in the United Arab Emirates. J. Arid Environ. 37, 505–512. Kim, B.J., 2005. The ghost ant as a potential house pest in Korea. Hankook Daily News dated on November 29, 2005. http://news.hankooki.com/lpage/society/200511/ h2005112911030122040.htm (accessed on October 15, 2008) [In Korean]. Kim, B.J., Kim, K.G., 1999. Systematic study of Dolichoderinae (Hymenoptera: Formicidae) in Korea. Korean J. Entomol. 29, 17–22. Nickerson, J.C., Bloomcamp, C.L., 2006. Ghost Ant Featured Creatures Institute of Food and Agriculture Science. University of Florida. http://creatures.ifas.ufl.edu/urban/ ants/ghost_ant.htm (Accessed on March 18, 2008).
69
Smith, M.R., 1965. House-infesting ants of the eastern United States; their recognition, biology, and economic importance. USDA Tech. Bull. 1326, 105. Smith, D.R., 1991. Ants (Formicidae, Hymenoptera). In Insect and Mite Pests in Food. An Illustrated Key Vol 1. J.R. Gorham (ed) USDA ARS Agriculture Handbook No. 655. Sorvari, J., 2002. Tapinoma melanocephalum (Fabricius, 1793) (Hymenoptera: Formicidae), an imported ant species new to Finland, with observations and a taxonomic note. Entomol. Gaz. 53, 269–270. Steinbrink, H., 1987. Ein weiterer Nachweis von Tapinoma melanocephalum (Hymenoptera, Formicidae) in der DDR. Angew. Parasitol. 28, 91–92. Terayama, M., Okutani, T., 1992. Occurrence of a House Infesting Ant, Tapinoma melanocephalum (Fabricius) (Insecta, Hymenoptera) in Tokyo, Japan. House and Household Insect Pests 14: 7–8 [In Japanese]. Terayama, M., Choi, B.M., Kim, C.H., 1992. A check list of ants from Korea, with taxonomic notes. Bull. Toho. Gakuen 7, 19–54. Wheeler, W.M., 1910. Ants, Their Structure, Development and Behavior. Columbia University Press, New York and London, p. 663. Wheeler, W.M., 1927. Chinese ants collected by Professor S.F. Light and Professor N. Gist Gee. Am. Mus. Novit. 255, 1–12. Wheeler, W.M., 1928. Ants collected by Professor F. Silvestri in Japan and Korea. Bull. Lab. Zool. Agr. Portici. 21, 96–125.
Contents lists available at ScienceDirect
Journal of Asia-Pacific Entomology j o u r n a l h o m e p a g e : w w w. e l s ev i e r. c o m / l o c a t e / j a p e
Tapinoma melanocephalum (Fabricius), a new exotic pest in Korea Hyon Chong Choe a,⁎, Jong Ok Lim b, Seunghwan Lee b a
106th Medical Detachment (Veterinary Service), United States Forces Korea, Yongsan Garrison, APO AP 96205, Seoul, Republic of Korea Entomology Program, Department of Agricultural Biotechnology and Research Institute for Agriculture and Life Science, Seoul National University, San 56-1, Sillim-dong, Gwanak-gu, Seoul, Republic of Korea
b
a r t i c l e
i n f o
Article history: Received 24 July 2008 Revised 8 December 2008 Accepted 11 December 2008 Keywords: Tapinoma Melanocephalum Exotic species Establishment Korea
a b s t r a c t Tapinoma melanocephalum (Fabricius) is established as a house pest in various regions of the world, not limited to its original climate zones. T. melanocephalum seems likely to become established in Korea as well, based on our observations of the species from a private house in Seoul, Korea, its history of establishment in the world, and a few unofficial records in Korea. Diagnosis of the species is provided with pictures of specimens. Morphological characteristics identifying T. melanocephalum from the Korean indigenous Tapinoma species are provided. © Korean Society of Applied Entomology, Taiwan Entomological Society and Malaysian Plant Protection Society, 2008 Published by Elsevier B.V. All rights reserved.
Introduction Tapinoma melanocephalum (Fabricius) is one of the most common house pest ants in the world. The ant lives in human dwellings and feeds on various household foods. They have a preference for sweet food and have been observed feeding on sugar, cake, and syrup (Smith, 1965). Indoor nests are usually in small spaces such as cracks, spaces between books, or wall voids. Foragers are found on kitchen sinks, counters, and floors. They can nest outside as well. Outside nests are usually in disturbed areas, such as in flowerpots, under objects on the ground, under loose bark, or at the bases of palm fronds. Outside, the workers scavenge for dead insects and tend sapsucking insects to collect honeydew (Nickerson and Bloomcamp, 2006). Until the 1970s, distribution of T. melanocephalum was limited to tropical and subtropical regions. They are common pests in Florida, Hawaii, and a few tropical islands (Nickerson and Bloomcamp, 2006). T. melanocephalum has been introduced or has become established in other regions of the world through commerce. Its distribution has expanded to temperate latitudes where they can overwinter inside of human dwellings with heated conditions, such as greenhouses and buildings. They have been reported as far north as the northern Nearctic regions, in Ontario, Winnipeg, and Monitoba in Canada. They have recently been reported as introduced or established in Germany (Steinbrink, 1987), Japan (Terayama and Okutani, 1992), the United Arab Emirates (Colling⁎ Corresponding author. Fax: +82 2 7918 5104. E-mail address: [email protected] (H.C. Choe).
wood et al., 1997), Australia (Andersen, 2000), and Finland (Sorvari, 2002). They move quickly and erratically when they are disturbed. Sometimes they show trailing movements, which are much slower and deliberate (Nickerson and Bloomcamp, 2006). The common name “ghost ant” is because of their fast moving behavior. The authors confirm T. melanocephalum for the first time in Korea. In this paper, diagnosis of T. melanocephalum is provided with pictures and specimen records. Morphological characteristics to differentiate T. melanocephalum from the indigenous Tapinoma species in Korea are provided. The status of risk of establishment is briefly discussed. It concluded that the ant seems at a risk of establishment, based on the authors' findings of the species from Seoul, its history of establishments in the world, and previous records in Korea. Materials and methods Specimens were collected by Mr. Yun Chan Song and provided to the authors. According to him, many individuals were observed in his private house from December 2007 to August 2008. The house is located in the eastern area of Seoul (Amsa-dong, Gangdong-gu). The ants disappeared from his house in June and July. The ants moved very fast and arbitrarily, and they were strongly attracted to pet foods. Specimens were identified with a guidance of taxonomic information and terms of Smith's (1991) and Bolton's (1994). A stereoscopic microscope (Leica, BE/S8APO) and a digital camera system (Diagnostic Instrument Inc., 14.2 Color Mosaic) were used for examination
1226-8615/$ – see front matter © Korean Society of Applied Entomology, Taiwan Entomological Society and Malaysian Plant Protection Society, 2008 Published by Elsevier B.V. All rights reserved. doi:10.1016/j.aspen.2008.12.003
68
H.C. Choe et al. / Journal of Asia-Pacific Entomology 12 (2009) 67–69
of the specimens. Identification was confirmed by Dr. Mamoru Terayama (Laboratory of Applied Entomology, University of Tokyo) and specimens are deposited in the Insect Museum of Seoul National University, Seoul, Korea.
Discussion
Taxonomic accounts
Three Tapinoma species have been reported in the Korean peninsula: T. geei Wheeler 1927, T. sinense Wheeler 1925 and T. wroughtoni Forel 1904. They have only been recorded from North Korea thus far (Terayama et al., 1992; Kim and Kim, 1999). Tapinoma melanocephalum (F.) is differentiated from the native Korean Tapinoma species by color patterns and a few morphological characteristics. T. melanocephalum is distinctively bicolored, while the native species are wholly dark. T. melanocephalum does not have a notch on the clypeus, but T. geei has a distinctive notch on clypeus (Fig. 1B). T. melanocephalum can be distinguished from T. sinense and T. wroughtoni by the relative lengths of antennal scapes. Scapes of T. sinense are longest, surpassing the occipital border by one-fourth of the length. Scapes of T. melanocephalum are shorter than those of T. sinense, only slightly overreaching the occipital border. In T. wroughtoni, scapes scarcely overreach the occiput (Collingwood, 1976; Wheeler, 1927 and 1928). Monomorium pharonis (Linnaeus) is a native ant species in Korea, which can be confused with T. melanocephalum. Both species are small and are bicolored. Identification of the two species requires microscopic examinations. The color patterns are slightly different. In T. melanocephalum, the gaster is wholly pale. In M. pharonis, only the first segments are pale and the remaining gastral segments are brown or dark. The two species belong to different subfamilies. T. melanocephalum has a clear promesonotal suture, as a typical species in the subfamily Dolichoderinae. M. pharonis has indistinct promesonotal suture and carries a constriction between third and fourth abdominal segments, as a typical species of the subfamily Myrmecinae (Choi, 1987; Bolton, 1994) (Figs. 1C, D).
Family Formicidae Subfamily Dolichoderinae Tapinoma melanocephalum (Fabricius) Diagnosis. [Worker] Body 1.3–1.8 mm long. Body is bicolored. Head is brown to dark brown. Antennae, mandible and maxillary appendages are pale brownish to yellowish white, or opaque. Mandibles have smooth margins. Alitrunk is dark brown as heads or sometimes a little paler than heads. Gaster and legs are opaque, yellowish or white. Antennae are long, and the scapes surpass the occiput slightly (Fig. 1A). Specimens examined. 10 workers. Amsa-dong, Gangdong-gu, Seoul, Korea. Yun Chan Song.
Morphological differences of T. menalocephalum from the Korean indigenous Tapinoma species and Monomorium pharonis (L.)
Risk of establishment in Korea Tapinoma melanocephalum seems likely to become established in Korea, based on the authors' observation of its survival for several months in Korea and its history of establishment worldwide. The origin of T. melanocephalum is assumed to be tropical and subtropical (Wheeler, 1910), but it has been introduced and established in various regions not limited to their original climate zones. T. melanocephalum survived in various regions of temperate latitudes by nesting inside heated human dwellings. Since 2005, T. melanocephalum has been unofficially recorded in Korea. Most records were apparently based on information from an entomologist's article, describing the introduction of the ghost ant in Korea and its potential risk as a pest if they become established (Kim, 2005). The identifications on the records were based on body size and color and movement patterns. They were published online and without confirmation of collection localities and dates, or examination of morphological characters. Many of the records are assumed to be correct, because T. melanocephalum is easily distinguishable by its erratic movements, body size and color pattern. Previous unofficial records support the authors' assumption that T. melanocephalum has been introduced to Korea and will likely become established. Acknowledgments
Fig. 1. Tapinoma melanocephalum (Fabricius) worker: A, whole body; B, head; C, D, alitrunk (C — dorsal view, D — lateral view).
The authors cordially thank Mr. Yun Chan Song, who collected the samples and provided them with information. Our gratitude is extended to Dr. Mamoru Terayama (Laboratory of Applied Entomology, University of Tokyo) for his confirmation of identification.
H.C. Choe et al. / Journal of Asia-Pacific Entomology 12 (2009) 67–69
References Andersen, A.N., 2000. Ants of Northern Australia: A Guide to the Monsoonal Fauna. CSIRO Publishing, p. 106. Bolton, B., 1994. Identification Guide to the Ant Genera of the World. Harvard University Press, p. 222. Choi, B.M., 1987. Taxonomic study on ants (Formicidae) (1) — on the genus Monomorium. Chongju National University of Education. Sci. Math. Educ. Publ. 11, 17–30 [In Korean]. Collingwood, C.A., 1976. Ants (Hymenoptera, Formicidae) from North Korea. Ann. Hist-nat. Mus. Nat. Hung. 68, 298–309. Collingwood, C.A., Tigar, B.J., Agosti, D., 1997. Introduced ants in the United Arab Emirates. J. Arid Environ. 37, 505–512. Kim, B.J., 2005. The ghost ant as a potential house pest in Korea. Hankook Daily News dated on November 29, 2005. http://news.hankooki.com/lpage/society/200511/ h2005112911030122040.htm (accessed on October 15, 2008) [In Korean]. Kim, B.J., Kim, K.G., 1999. Systematic study of Dolichoderinae (Hymenoptera: Formicidae) in Korea. Korean J. Entomol. 29, 17–22. Nickerson, J.C., Bloomcamp, C.L., 2006. Ghost Ant Featured Creatures Institute of Food and Agriculture Science. University of Florida. http://creatures.ifas.ufl.edu/urban/ ants/ghost_ant.htm (Accessed on March 18, 2008).
69
Smith, M.R., 1965. House-infesting ants of the eastern United States; their recognition, biology, and economic importance. USDA Tech. Bull. 1326, 105. Smith, D.R., 1991. Ants (Formicidae, Hymenoptera). In Insect and Mite Pests in Food. An Illustrated Key Vol 1. J.R. Gorham (ed) USDA ARS Agriculture Handbook No. 655. Sorvari, J., 2002. Tapinoma melanocephalum (Fabricius, 1793) (Hymenoptera: Formicidae), an imported ant species new to Finland, with observations and a taxonomic note. Entomol. Gaz. 53, 269–270. Steinbrink, H., 1987. Ein weiterer Nachweis von Tapinoma melanocephalum (Hymenoptera, Formicidae) in der DDR. Angew. Parasitol. 28, 91–92. Terayama, M., Okutani, T., 1992. Occurrence of a House Infesting Ant, Tapinoma melanocephalum (Fabricius) (Insecta, Hymenoptera) in Tokyo, Japan. House and Household Insect Pests 14: 7–8 [In Japanese]. Terayama, M., Choi, B.M., Kim, C.H., 1992. A check list of ants from Korea, with taxonomic notes. Bull. Toho. Gakuen 7, 19–54. Wheeler, W.M., 1910. Ants, Their Structure, Development and Behavior. Columbia University Press, New York and London, p. 663. Wheeler, W.M., 1927. Chinese ants collected by Professor S.F. Light and Professor N. Gist Gee. Am. Mus. Novit. 255, 1–12. Wheeler, W.M., 1928. Ants collected by Professor F. Silvestri in Japan and Korea. Bull. Lab. Zool. Agr. Portici. 21, 96–125.