DProceeaphnisd ingsplaci ofda ,the a N Hewawaiian Sphin Ex ntomologicalMoth for Gua Smociety (2015) 47:79–81 79

NEW RECORDS AND ACCOUNTS

Daphnis placida, a New Species of Sphinx for Guam, U.S.A.

Daniel Rubinoff1 and Ian Kitching2 1310 Gilmore Hall, Department of Plant and Environmental Protection Sciences, University of Hawaii, Honolulu, HI. 96822, USA 2Department of Life Sciences, Natural History Museum, Cromwell Road, London SW7 5BD, UK. Corresponding author: [email protected]

Guam, the largest of the Mariana ed. The Ritidian Point area where the D. Islands, has been the subject of a long placida was found is shared with Hasora series of invasions, dating back to hu- chromus (Cramer, [1780]), Hesperiidae, a man colonization and our commensals skipper butterfly that is also widespread almost 4,000 years ago. The invasion of across southeast Asia but is only found in the Brown Tree Snake (Boiga irregularis the Mariana islands at Ritidian point on ) in the 1940s led to the extermination Guam (Schriener and Nafus, 1997). This of virtually all of Guam’s native birds. skipper was, in fact, sighted the same day The more recent invasion of the Coconut by the first author, not far from where the Rhinoceros Beetle (Oryctes rhinoceros) is D. placida was found. It is possible that devastating native and ornamental palms the Ritidian Point area serves as a refuge across the island. Thus, understanding the for some native Guamanian which nature of any invasion in Guam may be are now, or always were, highly restricted helpful in preventing future challenges to on the island. Unless D. placida becomes its beleaguered ecosystems. much more common and widespread in On April 7, 2015, while conducting coming years, it is conceivable that a small biological surveys on Andersen Air Force population has been resident on Ritidian Base, the first author encountered a pair Point for a very long time and that, rather of sphinx that were perched on a than representing a new invasion, this spe- fence, facing each other, strongly suggest- cies is yet another isolated native species ing that they had been in copula the night that has until now escaped notice. before. Only the female was captured, The larval host plants of D. placida on and subsequently identified by the second Guam are unknown. In Australia and the author as Daphnis placida (Walker, 1856), Solomon Islands, the recorded plants are a species not previously recorded from Alstonia, Ochrosia, Tabernaemontana Guam. The specimen is deposited in the (all Apocynaceae) and Alangium (Corna- University of Hawaii Museum. ceae) (Bigger, 1988; Moulds, 1998). There D. placida is widespread across Aus- are no Cornaceae on Guam but there are tralasia, though it rarely comes to light, the endemic Ochrosia mariannensis and making it uncommonly seen by those not Tabernaemontana rotensis, the latter of specifically searching for it. Thus, it is which is only found on northern Guam not clear whether this species represents a and, sparsely, on the island of Rota, just new, recent invasion of Guam, or a native to the north. T. rotensis is quite rare and species that has previously gone undetect- has been proposed for listing as threatened 80 Rubinoff and Kitching

Figure 1. Dorsal view of Daphnis placida female from Guam.

Figure 2. Ventral view of Daphnis placida female from Guam.

Daphnis placida, a New Sphinx Moth for Guam 81 under the United States Endangered Spe- work benefitted from ongoing survey work cies Act. If D. placida is native to Guam, supported by the U.S. Fish and Wildlife then it is unlikely to threaten T. rotensis; Service. Rubinoff was also supported by however if it is a new arrival, then it could the USDA National Institute of Food and pose a threat to this rare plant. Agriculture, Hatch project HAW00956-H, managed by the College of Tropical Agri- Acknowledgments culture and Human Resources, University We thank M. Wright (University of Ha- of Hawaii. waii), B. Holland (University of Hawaii) and A. Gawel (U.S. Fish and Wildlife Literature cited Service) for assistance in the field, A. Bigger, T.R.L. 1988. The insect pests of for- Gawel for expertise in identifying possible est plantation trees in the Solomon Islands. hostplants, and L. Wada (U.S. Fish and Solomon Islands Forest Record 4: 1–190. Moulds, M.S. Wildlife Service) for invaluable support 1998. New larval food plants for Australian hawk moths (: across many aspects of this study. We ) Australian Entomologist 25: thank Dana T. Lujan, NAVFAC Mari- 13–22. anas, 36th Civil Engineering Squadron, Schriener, I. H. and D. M. Nafus. 1997. But- Andersen Air Force Base for facilitating terflies of Micronesia. University of Guam access and funding for this survey. This Press. 82 Rubinoff and Kitching