The Longicorn Beetles of Hainan Island

The Philippine Journal of Science Vol. 72 MAY-JUNE, 1940 Nos. 1-2 THE LONGICORN BEETLES OF HATNAN ISLAND 1 COLEOPTERA : CERAMBYCIDiE By J. Linsley Gressitt Of the Lingnan Natural History Survey and Museum Lingnan University, Canton, China EIGHT PLATES The present report is in the nature of a classification of the longicorn, or long-horned, beetles hitherto collected on Hainan Island, as far as available to the writer. A large part of the material on which the work has been based is included in the collections of the Lingnan Natural History Museum of Lingnan University, Canton, made on various expeditions, principally by F. K. To in 1932 and 1935, by Prof. W. E. Hoffmann, Mr. 0. K. Lau, and Dr. F. A. McClure in 1932, and by the Fifth Hainan Island Expedition of the University in 1929, as well as on collections made by myself on my trip (34) to the island during the summer of 1935. The remainder of the material studied includes, among others, part of the collection made by Mr. J. Whitehead in 1899, and the specimens collected by Commander G. Ros in the spring of 1936. A list of localities is given at the end, in addition to the map, in order to facilitate the identification of place names used. I am deeply grateful to Professor W. E. Hoffmann, director of the Lingnan Natural History Survey and Museum of Lingnan University, for enabling me to make this study. To Dr. K. G. Blair, of the British Museum of Natural History, I am greatly 1 Contribution from the Lingnan Natural History Survey and Museum of Lingnan University, Canton, China. 39937 1 : The Philippine Journal of Science 1940 indebted for sending me Hainan specimens for study, including some of Whitehead's material, as well as for kindly comparing specimens for me with types in the British Museum. I am likewise indebted to the Reverend Pere Octave Piel, of the Musee Heude, Universite PAurore, Shanghai, for generously submit- ting to me for study the specimens collected by Commander Ros. I wish also to express my deep appreciation to Mr. W. S. Fisher, of the United States National Museum, and Drs. E. C. van Dyke and E. Gorton Linsley, of the University of Ca- lifornia, for cooperation extended during the course of this study. Dr. F. A. McClure has very kindly supplied information concern- ing localities in Hainan. The type specimens of the new species are deposited in the United States National Museum in Washington, D. C. ; the Ling- nan Natural History Museum in Canton, China; the California Academy of Sciences in San Francisco; the British Museum in London; and the Musee Heude, Universite FAurore, Shanghai. The holotypes in the California Academy of Sciences are placed on loan deposit as part of my own collection, pending the final deposition of the latter. HISTORICAL The first paper on the Cerambycidae of Hainan Island, and the only previous paper to deal with them exclusively, was pub- lished by Gahan(i9) in 1900, and was based on the specimens collected by J. Whitehead on the island during the preceding year. In that paper the following 24 forms were listed, 22 of which were identified, and 6 (here preceded by asterisks) described as new species * JEgosoma hainanensis Gahan. Melanaiister chinensis Forst. JEgosoma, marginale (Fabr.). * Melanauster macrospilus Gahan. Philus antennatus Saund. Coptops polyspila Pasc. Dialeges undulatus Gahan. Olenocamptus bilobus (Fabr.). Ceresium sinicum White. * Niphona Hookeri Gahan. Eurybatus 10-punctatus Westw. Pterolophia annulata Chevr. Clytanthus douei Chevr. var. Zotale lineata (Gahan). Chlorophorus annularis (Fabr.). Sybra posticata Gahan. Xylotrechus quadripes Chevr. var. Serixia sedata Pasc. Monohammus bimaculatus Gahan. Serixia sp. * Pelargoderus apicalis Gahan. * Astathes cyanoptera Gahan. * Melanauster similis Gahan. Oberea sp. In addition was mentioned an undescribed species of a new genus allied to Merionceda, which has been sent me by Dr. Blair and is herein described as a new species of Kunbir. A 72,1-2 Gressitt: Longicorn Beetles of Hainan 3 few changes in Gahan's identifications are also proposed in the present work. "Clytanthus douei Chevrolat var." may possibly be one of the two species of Chlorophorus herein named. Since the publication of Gahan's paper no new species have been described from the island, and only two additional species have been recorded: Paraphrus granulosus Thomson by La- meere(43) in 1911, and JEolesthes sinensis Gahan by Liu(49, p. no) in 1934. As to the correctness of the latter identification, however, I am uncertain. PHYSICAL FEATURES OF HAINAN Hainan is a large, though little-known island, occupying an important place in the Gulf of Tonkin (Tongking) in the South China Sea, just south of the southern extremity of China, which, in the form of the Luichow Peninsula, approaches to within 25 kilometers of the island, Hainan lies a few hundred kilometers east of Tonkin, northern French Indo-China. The area of the island is in the neighborhood of 35,800 square kilometers (14,000 square miles), and its greatest length is about 290 kilometers (180 miles), in a southwest-northeast direction. Hainan ex- tends from 18° 9' to 20° 8' north latitude and 108° 36' to 111° 3' east longitude, being a little south of Formosa, Hawaii, and Lower California, with the middle of the island just south of the northern end of Luzon. Though similar to Formosa in area and in relation to the continent, the island is much less mountainous and less heavily forested than the latter, and in some respects seems poorer in its fauna, in spite of its more tropical location. The northern portion of Hainan, and the northwestern coastal area, are largely level, being partially cultivated, and in part almost desertlike, with low grass and scattered palms. The central and southern parts of Hainan are mountainous, with several long ranges extending in different directions. The highest mountains are a little less than 2,000 meters (6,500 feet) in altitude, and are covered with dense jungle, at least on their upper slopes. There are no volcanoes on the island, though there are a few low eroded cones, "The Hummocks,'* near the northern end of the island. There are four principal rivers, emptying into the ocean on as many sides of the island, and all originating in the mountains of the central part. The climate is tropical, with high humidity and heavy rains, particularly those brought by the summer monsoons and ty- phoons from the east and southeast, across the Philippines and 4 The Philippine Journal of Science iuo the South China Sea. The climatic conditions differ consider- ably in the extreme southern part of the island, which is much warmer, with more distinct wet and dry seasons, than the central and northern sections, and this part apparently posses- ses a fauna distinctively different from that of the rest of the island. Unfortunately not much material is available from the southernmost portion. ZOOGEOGRAPHY Hainan is distinctly Indo-Chinese in the character of its ani- mal inhabitants. The last connection of the island with the mainland was very likely through the Luichow Peninsula, un- less the northern part of the Gulf of Tonkin was submerged during the process of separation. Unfortunately the faunas of the Luichow Peninsula and of western Kwangtung Province are as yet little known, so it cannot be definitely stated whether the fauna of Hainan is more closely related to that of northern Indo-China or to that of the southern extremity of the Chinese mainland. Most likely the relationship of the three areas will show no very striking differences, and the fauna of Hainan will not prove to possess as high a percentage of endemicity as is indicated by the large proportion of forms described as new species or new subspecies in this work. In a recent study on the mainland Kwangtung fauna(35) in this family of beetles, only 25 of the 143 species considered were known to me to be found on Hainan, but in the present work 38 of the 167 species are recorded also from mainland Kwangtung. This apparently great difference between the two areas can be explained to some degree by the fact that the collections at hand probably rep- resent only a small fraction of the actual fauna in both cases, and also by the fact that the Kwangtung material studied largely came from the northern and northeastern extremities of the province, and most of the Hainan material from the south central part of the island. The relationship of the Hainan fauna with that of Burma and Siam seems to be very close, and doubtless many of the species here recorded from Hainan and one or both of the other two mentioned regions will later be found also in Indo-China or in the southwestern corner of China. The geographical affinities of the Hainan longicorns, as far as the distribution of the various species is known, shows the following order of relationship with other regions, according to 72,1-2 Gressitt: Longicorn Beetles of Hainan 5 the number of species held in common with Hainan: South China mainland, 47 species ; Formosa, 36 ; Indo-China, 34 ; Burma 28; Siam, 24; Hongkong, 21; India, 20; Malay Peninsula, 14; Assam, 14; Sunda Islands, 13; Ryu Kyu (Loochoo) Islands, 7; Japan proper, 7 ; Central China, 5 ; Andaman Islands, 5 ; Ceylon, 4; Wallacea, 4; North China, 3; Philippine Islands, 2; Korea, 2; and West China, Tibet, Africa, and the Bonin Islands with 1 species each in common with Hainan. One of the striking facts is the paucity of species (two) held in common with the Philippines, whereas the latitude is practically the same and the distance separating the two regions not very great.

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