摘要 麗松鼠屬（Callosciurus）包含了15種松鼠，廣泛分佈在亞洲南方，以往根據腹部毛皮顏色類型將台灣地區赤腹松鼠（C. erythraeus）歸類出3個亞種（C. e. thaiwanensis, C. e. centralis與C. e. roberti）。為了解決台灣地區赤腹松鼠的亞種地位及地理親緣關係，本研究中採用分子與形態學的方法加以探討。取自台灣29個地點70隻赤腹松鼠定序出粒線體DNA控制區的完整序列（1,079-1,081 bp）。以neighbor-joining法建構親緣關係樹，顯示台灣的赤腹松鼠可區分成3個主要系群：台灣東部與恆春半島區（Group 1）、台灣西南部（Group 2）與台灣西北部（Group 3）。3個系群的單套型歧異度與核?酸歧異度分別為0.945至0.964與0.71至1.32%。3個系群之間的平均遺傳距離相近（0.0261-0.0272），且核?酸分歧指數也相似（2.51-2.61%）。族群分化指數（Fst）與基因交流度（Nm）指出Group 1與Group 2之間存有較頻繁的基因交流，而Group1與Group3與Group2與Group3之間則相對較少的基因交流。頭骨形態以主成分分析及典型區別分析發現在3個系群之間並沒有呈現顯著差異。2或3種腹部毛皮顏色型式皆可共同存在每個系群中。本研究推論台灣的地理條件中，中央山脈、濁水溪及蘭陽溪可能是台灣赤腹松鼠族群地理隔離的重要障礙。本研究並討論在冰河時期赤腹松鼠至少有2處台灣中部與台灣東南方的避難所。 Abstract Squirrels belonging to the genus Callosciurus are widely distributed in Southeast Asia are classified into 15 species. In Taiwan, the population of C. erythraeus is divided into three subspecies (C. e. thaiwanensis, C. e. centralis and C. e. roberti) based on ventral pelage color patterns. To resolve the subspecific status and phylogenetic relationships of C. erythraeus of Taiwan, the molecular and morphological methods were used. The mitochondrial DNA control region sequences (1,079-1,081 bases) of C. erythraeus were determined for 70 specimens from 29 locations in Taiwan. Phylogenetic relationships reconstructed by neighbor-joining method indicated that the Taiwan population is separated into three major lineages: East Taiwan and Hengchun Peninsula (Group 1), Southwest Taiwan (Group 2) and Northwest Taiwan (Group 3). The haplotype diversity and nucleotide diversity of three lineages were 0.945-0.964 and 0.71-1.32%, respectively. The mean genetic distance among three lineages was similar (0.0261-0.0272), and the nucleotide divergence among them was also similar (2.51-2.61%). The fixation index (Fst) and gene flow (Nm) values indicate some gene flow between Groups 1 and 2, but relatively few between Groups1 and 3 or Groups 2 and 3. The morphometric differences of skulls among three lineages were not significantly separated based on principal component analysis and canonical discriminant analysis. Two or three ventral pelage color patterns were found in each lineage. The Central Mountain Range, the Choshui River and the Lanyang River probably play important roles in the geographic isolation of the C. erythraeus populations in Taiwan. At least two major glacial refugia of C. erythraeus might have been formed in central and southeast Taiwan was discussed.
