Invertebrates (pdf)

	New Planaeschna record from Hong Kong (Odonata: Aeshnidae)
	Sinthusa nasaka (Horsfield) (Lepidoptera: Lycaenidae), a butterfly new to Hong Kong
	A new record for Hong Kong and China of a Polistine wasp of the genus Ropalidia : Ropalidia mathematica (Vespidae: Polistinae: Ropalidiini)

Sinthusa nasaka (Horsfield) (Lepidoptera: Lycaenidae), a butterfly new to Hong Kong (pdf)

by Philip Yik Fui Lo, Hui Wing Leung and Leung Wo Kwai

Agriculture, Fisheries and Conservation Department, 6/F., Cheung Sha Wan Government Offices, 303 Cheung Sha Wan Road, Kowloon, philiplo@hkstar.com

Sinthusa Moore, 1884, comprises about a dozen small species (Bascombe,1999), distributed from India to Taiwan, including Sundaland, the Philippines and Sulawesi (Eliot, 1992). In the last decade, several new taxa in this genus, such as S. zhejiangensis Yoshino, 1995 and S. menglaensis (Wang, 1997) were discovered in Southern China, which may reflect the high diversity of the genus in this region. In Hong Kong, this genus has been only represented by a single species, S. chandrana (Bascombe,1999; Lo & Hui, 2004).

In butterfly surveys conducted in Hong Kong during the summer of 2004, several female specimens of a suspected Sinthusa species were found (Fig. 1). The publication of the discovery has been delayed for almost two years because meaningful taxonomic comparison could not be done until a male specimen was collected in July 2005, and the identity of this lycaenid was then confirmed to be S. nasaka.

Fig.1. Distribution of S. nasaka ssp. in Hong Kong. (Circle denotes record with voucher specimen; square denotes photograph record from Yim, Chong, Yiu & Yiu). (click for larger map)

It is worth noting that previously published and illustrated records of this species in China appear to be all female (Gu & Chen, 1999; Wang & Fan, 2002; Chou, 1994); the male S. nasaka of the race in China is thus illustrated and described here for the first time.

Materials and Methods

Apart from materials found in Hong Kong, specimens of S. nasaka amba (Kirby, 1878) from the Malay Peninsula were used in this study for comparison. Voucher specimens will be deposited in the Agriculture, Fisheries and Conservation Department, Hong Kong (AFCD).

Comparative materials examined:

Sinthusa nasaka amba (Kirby, 1878)

1♀, Malaysia, Perak, May 2005; 1♂1♀, same loc., June 2005, coll. local collector (1♂ genitalia dissected: YFL ly0007).

The genitalia of male specimens were prepared using the following procedures. The abdomen was first removed and placed in 10% NaOH under room temperature for 24 hrs to dissolve the soft tissue. It was then transferred to 70% ethanol and dissected under a stereomicroscope. The dissected genitalia were preserved in 70% ethanol and labelled properly for further study.

Result

Having compared the male genitalia of specimens from Hong Kong and the Malay Peninsula, no major difference was found and their similarities reveal their conspecific relationship.

Specimens examined

Sinthusa nasaka (Horsfield, 1829) ssp.

3♀, Pat Sin Leng Country Park, 200m, 22/23 June 2004, coll. W. K. Leung & W. L. Hui (AFCD); 1♀, same loc., 26 June 2004, coll. Y. F. Lo & W. L. Hui (AFCD); 1♀, Tai Mo Shan Country Park, 400m, 09 July 2004, coll. Y. F. Lo & W. L. Hui; 1♂, Shing Mun Country Park, 500m, 23 July 2005, coll. W. L. Hui (genitalia dissected: YFL ly0001).

Diagnostic Features of Sinthusa nasaka ssp. in Hong Kong

Male (Figs. 2 & 3)

Forewing: termen, costa slightly convex, dorsum convex at base. Ground colour of upperside oily blue. Ground colour of underside brownish grey. Cell-end stripe forming double pale brown bars. Post-discal band brownish orange bar outwardly edged with thin white line, running from Rs₂ toward CuA₂; submarginal and marginal bands faint, only slightly darker than ground colour. Hindwing: wing tail at the end of CuA₂; tornal lobe present but small. Ground colour of upperside bright blue, tornal lobe with orange and metallic blue scaling. Ground colour of underside brownish grey.

Fig. 2. Upperside of S. nasaka ♂: Shing Mun Country Park, 500m, 23 July 2005, coll. WL Hui

Cell-end stripe forming double pale brown bars. Post-discal spot forming brownish orange broken bar edged with black and white line on both sides, from Sc+R₁ towards CuA₂ and a "V" shaped band forming in space CuA₂ and 2A. Submarginal and marginal bands zigzag shaped and barely seen. A dark spot enclosed by orange circle in space CuA₁, orange and metallic blue patch in space CuA₂. Tornal lobe dark brown with metallic blue scaling.

Fig. 3. Underside of S. nasaka ♂: Shing Mun Country Park, 500m, 23 July 2005, coll. W.L. Hui

Male secondary sexual characters: scent brand across the origin of R_s on upperside of hindwing and a hair tuft on the forewing underside dorsum.

Male genitalia: (Fig. 4) typical form of the genus. Valvae long and narrow. Phallus long, a distant pointed process at the dorsal posterior end of aedeagus.

Fig. 4. Male genitalia of S. nasaka ssp. in Hong Kong: A. ventral view of valvae; B. lateral view of 9th + 10th sclerites; C. lateral view of phallus. Scale bar = 1mm.

Female (Figs. 5 & 6)

Forewing: termen, costa slightly convex, dorsum straight. Ground colour of upperside dark brown. Ground colour of underside silvery grey. Wing patterns similar to male, except for more pronounced submarginal and marginal bands. Hindwing: wing tail at the end of CuA₂; lobe present but small. Ground colour of upperside dark brown, tornal lobe with orange and metallic blue scaling. Ground colour of underside silvery grey. Wing patterns similar to male, except for darker submarginal and marginal bands.

Fig. 5. Upperside of S. nasaka ♀: Pat Sin Leng Country Park, 200m, 22/23 June 2004, coll. W. K. Leung & W. L. Hui

Fig. 6. Underside of S. nasaka ♀: Pat Sin Leng Country Park, 200m, 22/23 June 2004, coll. W. K. Leung & W. L. Hui

Other information

Immature biology: There is no information on immature stages of this species.

Occurrence: It is undoubtedly a multivoltine species. Adults are found between June and July; there are also photograph records taken in April and November (Yim, Chong, Yiu & Yiu, unpublished photograph records).

Distribution: China (Hong Kong, Fujian, Guangxi and Hainan), Sikkim to Burma, Thailand, Laos and Sunderland (Eliot, 1992; Osada et al, 1999; Pinratana, 1981; Wang & Fan, 2002; Xu & Jiang, 2001). In Hong Kong, it has scattered a distribution in the central and north-eastern New Territories.

Discussion

S. nasaka was once misidentified as Rapala refulgens in Chou (1994), but an amendment was made in the revised edition (Chou, 1999) subsequently. Meanwhile, the record of Rapala refulgens in Southern China (Bascombe, 1995) was probably an error adopted from Chou (1994).

S. nasaka inhabits woodlands and dense scrublands. It has rapid flight and often settles on vegetation for short periods. Males are rarely seen while females appear to be more common. Adults are attracted to flowers and were observed taking nectar from Mikania micrantha and Litchi chinensis (Yim & Yiu, unpublished photograph records). With S. chandrana-like habit and Rapala manea-like appearance, S. nasaka behaves like a combination of these two fairly common species. This probably explains why it has not been reported in earlier studies even though it has a fairly wide distribution. In fact, after examining albums of several amateur photographers, S. nanaka was found in some of their previous photographic records, and these provided additional information on the distribution of this newly recorded butterfly.

Acknowledgements

We would like to thank Kwok-leung Yip (AFCD) for giving us useful comments on the manuscript. Yik Man Yim, Paul Chong, Michael Yiu and Shiu Man Yiu provided unpublished photograph records of S. nasaka. Siu-ki Clive Lau (AFCD) provided literature relevant to this study. Colleagues from AFCD assisted greatly in field work.

Bibliography

Bascombe, M.J. (1995). Check list of the butterflies of South China. Memoirs of the Hong Kong Natural History Society, 20: 1-207.

Bascombe, M., Johnston, G.. & Bascombe, F. (1999). The Butterflies of Hong Kong. London: Academic Press.

Chou, I. (1994). Monographia Rhopalocerorum Sinensium. Zhengzhou, 1^st edition. Henan: Henan Science and Technology Press.

Chou, I. (1999). Monographia Rhopalocerorum Sinensium. Zhengzhou, revised edition. Henan: Henan Science and Technology Press.

Eliot, J.N. (1992). The Butterflies of the Malay Peninsula, 4^th edition (originally by Corbet, A.S. & Pendlebury, H.M.). Kuala Lumpur: Malayan Nature Society.

Gu, M.B. & Chen, P.C. (1999). Butterflies in Hainan Island. Beijing: China Forestry Publishing House.

Lo, Y.F. & Hui W.L. (2004). Hong Kong Butterflies. Hong Kong: Cosmos Books Ltd. and Friends of the Country Parks.

Osada, S., Uemura, Y. & Uehara, J. (1999). An Illustrated Checklist of the Butterflies of Laos P. D. R. Tokyo: Mokuyo-sha.

Pinratana, A. (1981). Butterflies in Thailand. Vol. 4: Lycaenidae. Bangkok: Viratham Press.

Wang, M. & Fan, X.L. (2002). Butterflies Fauna Sinica : Lycaenidae. Henan: Henan Science and Technology Press.

Xu, Q.H. & Jiang F. (2001). New Record of 8 Species of Butterflies in Fujian Province. Journal of Zhangzhou Teachers College (Nat. Sci.), 14(1): 17, 77-78.

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