| Summary: | 碩士 === 國立師範大學 === 生物學研究所 === 86 === Psechrid spiders are the largest among six cribellate families in Taiwan. They are characterized by their funnel webs of more than a meter wide and carry their eggs with chelicera. Among them, the Psechridae are born with nursery nature and grate-shaped tapetum eye structures, which are typical of the acribellate spiders. Levi (1982) hypothesized that Psechridae is close to acribellate spiders, e.g. Lycosidae, Pisauridae, Ctenidae and Oxyopidae. Furthermore, Coddington and Levi (1991) grouped them together as Lycosoidae superfamily based on their common features. In this work, DNA from both cribellate and acribellate spiders in Taiwan were extracted, and their mitochondrial 16S rDNA sequences were amplied. The samples sequenced from Taiwan for sequencing determination included cribellate Zosis geniculatus and Psechrus sp. as well as family of acribellate Nephila maculata, Dolomedes raptor, Lycosa coelestis, Pardosa takahashii, Oxyopes sertatus with Macrothele holsti as outgroup taxa. In addition, 16S rDNA sequences of Pardosa agrestis, Dolomedes fimbriatus, Clubiona pallidula, Cupiennius salei, Cupiennius getazi, Cupiennius coccineus previously published were analyzed altogether with the data obtained. The analysis indicated that Psecchridae are proved phylogenetically related to acribellate spiders based on their sequence homology, divergence, transition over transversion ratio and southern blotting. The data confirmed that Psechridae be placed close together with acribellate Lycosidae, Pisauridae, Ctenidae and Oxyopidae, but not with Zosis geniculatus. The polyphyly of the cribellate spiders is also proved. The preliminary data based on 16S rDNA also reveal geographical differentiation of Psechrid spiders in Taiwan. Further analysis with different markers is needed.
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