New Records of Butterflies (Lepidoptera) from the Eastern Caroline Islands, Micronesia1 Donald W. Buden,2,5 Donald P. Sands,3 and W. John Tennent4 Abstract: Twenty-three new locality records are presented for nine species of butterflies (Lepidoptera) from 11 islands and island groups in the eastern Car- oline Islands, Micronesia. None is endemic; most occur widely in the Indo- Australian region and the islands of the western Pacific. The Lycaenidae were the most well-represented family with at least eight species. The nymphalid Hypolimnas bolina was the most frequently encountered species, occurring on all 11 island groups. Pakin Atoll, which was visited on two different occasions for a total of 5 days, was the only island group visited during this study where but- terflies were not seen. The butterfly fauna of Micronesia has contributes new locality records based largely never been comprehensively assessed. Many on recent collections and observations from of the specimens collected during the Insects eight different islands and island groups in of Micronesia Project outlined by Gressitt the eastern Caroline Islands intermittently (1954) were apparently lost after being sent between November 2001 and August 2003, on loan overseas (S. E. Miller in Buden and plus supplementary material from the Bishop Miller 2003), and no article on butterflies Museum and a small, hitherto-unreported was ever published in the Insects of Micro- collection in the College of Micronesia Land nesia series. Schreiner and Nafus (1997) Grant Office (Kolonia, Pohnpei). summarized what little is known of the ecol- ogy and distribution of species among the Study Area major islands and island groups of greater Micronesia, including the Mariana Islands, The Caroline Islands span approximately Caroline Islands, and Marshall Islands. Buden 3,200 km across the West-central Pacific and Miller (2003) augmented the list of spe- Ocean from Palau eastward to and including cies from Pohnpei, but the other Caroline all of the Federated States of Micronesia Islands, especially the atolls, have remained (FSM): Yap, Chuuk (formerly Truk), Pohn- largely unsurveyed. The study reported here pei, and Kosrae States (Figure 1). Pohnpei (355 km2, 791 m high) and Kosrae (109 km2, 630 m high) are the largest of the eastern 1 Manuscript accepted 24 May 2004. 2 Carolines. Chuuk proper approaches atoll Division of Natural Sciences and Mathematics, status and comprises 19 volcanic islands (the College of Micronesia-FSM, P.O. Box 159, Kolonia, 2 Pohnpei, Federated States of Micronesia 96941 (e-mail: largest is Tol: 34.2 km , 443 m high) within [email protected]). a lagoon (2,130 km2) enclosed by a reef and 3 CSIRO Long Pocket Laboratory, Indooroopilly, its associated coral islets. Tropical rainforest Queensland 4068, Australia (e-mail: [email protected]). in various stages of degradation (less degra- 4 Biogeography and Conservation Laboratory, De- partment of Entomology, The Natural History Museum, dation on Pohnpei and Kosrae, more on London SW7 5BD, England (e-mail: jt@storment Chuuk) covers most of the slopes of the .freeserve.co.uk). higher islands. Cloud forest lush in terrestrial 5 Corresponding author. and epiphytic mosses and ferns occurs on the highest summits and ridgelines on Pohnpei Pacific Science (2005), vol. 59, no. 1:97–103 and Kosrae. Agroforest and secondary wood- : 2005 by University of Hawai‘i Press lands predominate at the lower elevations All rights reserved throughout and mangroves are common 97 98 PACIFIC SCIENCE . January 2005 Figure 1. Location of the Caroline Islands. along the shore. The average annual rainfall spp.) are the dominant trees on all but the ranges from about 363 cm in Chuuk (Merlin smallest atoll islands, where coastal scrub and and Juvik 1996) to 1,015 cm estimated in the strand predominate. All of the islands fall mountains on Pohnpei (Merlin et al. 1992). within the equatorial rain belt and are wet The land area on the numerous, wide- enough to support a mesophytic vegetation spread, low (1–4 m high) coralline atolls is (Mueller-Dombois and Fosberg 1998). All of miniscule. Satawan Atoll in the Mortlock the atolls visited during this survey are in- Islands, southern Chuuk State, has the largest habited or (in the case of Ant Atoll) have been total land area, with 4.6 km2 distributed so in the recent past. Ornamental shrubs, among approximately 49 islets (Bryan 1971). trees, and herbs are common in the settle- Houk (¼ Pulusuk Atoll), a lone islet west of ments, which are usually located on one or Chuuk Lagoon, is the largest single island several of the larger islets; the others are vis- (2.8 km2) among all of these outlyers. Coco- ited frequently to harvest coconuts, crabs, and nut (Cocos nucifera) and breadfruit (Artocarpus other forest products used by the community. Butterflies of the Eastern Caroline Islands . Buden et al. 99 materials and methods record from Kosrae, but this sight record re- quires confirmation.] Butterflies were collected by D.W.B. when the opportunity arose during biological sur- veys of several different taxonomic groups, Family Lycaenidae including birds, reptiles, odonates, and milli- Catochrysops panormus (C. Felder) pedes, on Chuuk Lagoon islands (20 June–2 Ranges widely from India and Sri Lanka July 2003), Onoun Island, Namonuito Atoll through Indonesia to eastern Australia, and in (3–7 January 2003), Houk Island (26 De- the Pacific as far east as the Society Islands cember 2002–2 January 2003), Satawan Atoll (Tite 1959, Seki et al. 1991, Braby 2000). (17–26 December 2002, 7 July–1 August In Micronesia, it has been recorded on Guam 2003), Pakin Atoll (7–9 August 2002, 5–7 (Parsons 1998) and Pohnpei (Buden and November 2003), Ant Atoll (28–31 March Miller 2003). During this study, C. panormus and 16–18 November 2001, and 10–11 May, was common on Nikalap Aru Island (Ant 7–8 September, and 6–9 November 2002), Atoll) and on Houk, Chuuk State. It was less Mokil Atoll (29 July–2 August 2002), Pinge- common on Onoun, Namonuito Atoll, where lap Atoll (29 March–1 April and 13–16 only one was collected and few others were December 2002), and Kosrae (20 June–6 seen. Nearly all were in coastal strand and July 2002). Specimens have been deposited forest edge where Canavalia sp. and Vigna in CSIRO Long Pocket Laboratory (In- marina vines were common. These are the dooroopilly, Australia) and The Natural His- first records from among the atolls of Micro- tory Museum (London). Sight records are nesia. enclosed in square brackets. Euchrysops cnejus (Fabricius) species accounts Ranges from India through Southeast Asia Family Pieridae to New Guinea, Australia, and the western Pacific islands as far east as Fiji and Tonga. (Fabricius) Catopsilia pomona Schreiner and Nafus (1997) recorded it in the Ranges widely from Madagascar to the western Carolines in Palau and Yap. We re- Solomon Islands, Vanuatu, and Fiji. It has port it from the eastern Carolines for the first been recorded in western Micronesia on time based on three previously unreported Palau and the Mariana Islands (Schreiner and specimens in the Bishop Museum: one from Nafus 1997), and Buden and Miller (2003) Dublon (¼ Tonoas) Island, Chuuk, and an- recorded it from Pohnpei in the eastern Car- other from Kusaie (¼ Kosrae), both collected olines. One collected at Utwa village and an- by Z. Ono in January 1936, and another from other along the Utwa-Walung road on 1 July Pohnpei collected by P. A. Adams in 1950. 2002, both apparently attracted to nearby Cassia alata, are the first reports from Kosrae. Jamides sp. (bochus group) Others were observed occasionally along More than 20 names have been proposed roadsides in different parts of the island dur- for the Jamides bochus species group in the ing 20 June–6 July. Pacific Islands, and the taxonomy and species limits within this complex are unresolved. [Catopsilia pyranthe (Linnaeus)] Schreiner and Nafus (1997) recorded J. bochus [Ranges widely from Southeast Asia (Stoll) in Micronesia on Palau and Pohnpei. southward to Indo-Australia and to as far east No example of this group was found on as Fiji (W.J.T., unpubl. data). Schreiner and Pohnpei during a more recent survey (Buden Nafus (1997) recorded it in Micronesia in and Miller 2003). However, 28 collected Palau and Yap, and Buden and Miller (2003) during two different visits to Satawan Atoll recorded it on Pohnpei. One seen along the (December 2002, July 2003) are the first re- Utwa-Walung road on 1 July 2002 is the only ports for Chuuk State. They were in open, 100 PACIFIC SCIENCE . January 2005 weedy areas and nearly always on or in close and mode of its initial arrival and colonization proximity to the vine Vigna marina. of Kosrae (and elsewhere in the Pacific) is unknown, but the species is known to have Lampides boeticus (Linnaeus) spread across the whole of the Pacific from Ranges widely from Africa and Europe to about the 1840s (Vane-Wright 1993). It may the Orient, Hawai‘i, Indo-Australia, and the have reached Pohnpei via a ship from Ha- Pacific Islands as far east as Fiji and Tonga. wai‘i, as suggested by Scudder (1875), or as a Schreiner and Nafus (1997) recorded it in direct result of its migrating ability in track- Micronesia only as far east as Chuuk, but ing the spread of Asclepias (milkweed) host Sugarman (1979) recorded Lampides sp. from plants brought through trade (Vane-Wright Kwajalein Atoll in the Marshall Islands, and 1993). Samuelson and Nishida (1987:165) referred One seen on Deke Island, Pingelap Atoll, to this record as ‘‘probably L. boeticus.’’ Only on 30 March 2002 (D.W.B.) is the only rec- two were encountered during this survey: one ord for an eastern Carolines atoll.