长尾姬鼠、中华姬鼠毛髓质指数比较及长尾姬鼠分类地位的探讨

关于长尾姬鼠(Apodemus orestes)的分类地位,一直没有确定。有的认为它是中华姬鼠(A．draco)的一个亚种,而有的认为是一个独立的种。分别从成体长尾姬鼠、中华姬鼠和高山姬鼠(A．chevrieri)(对照)各5只的胡须、头部、背部、腹部、前肢取毛样,清洗和处理后,在倒置显微镜下观察,用目镜测微尺分别测量和计算出其5个部位毛发的毛髓质指数。结果表明：长尾姬鼠与中华姬鼠5个部位及混合毛发的毛髓质指数无显著差异;二者5个部位及混合毛发的毛髓质指数与高山姬鼠均有显著差异。不支持长尾姬鼠作为一个独立种的观点。     

Histochemical evidence of β‐chitin in parapodial glandular organs and tubes of Spiophanes (Annelida,Sedentaria: Spionidae), and first studies on selected Annelida

A generic character of the genus Spiophanes (Annelida, Sedentaria: Spionidae) is the presence of parapodial glandular organs. Parapodial glandular organs in Spiophanes species include secretory cells with cup‐shaped microvilli, similar to those present in deep‐sea inhabiting vestimentiferans and frenulate Siboglinidae. These cells are supposed to secrete β‐chitin for tube‐building. In this study, transverse histological and/or ultrathin sections of parapodial glandular organs and tubes of Spiophanes spp. as well as of Glandulospio orestes (Spionidae) and Owenia fusiformis (Oweniidae) were examined. Fluorescent markers together with confocal laser scanning microscopy, and Raman spectroscopy were used to detect chitin in the parapodial glandular organs of Spiophanes and/or in the glands of Owenia and Glandulospio. Tubes of these taxa were tested for chitin to elucidate the use of it for tube‐building. The examinations revealed a distinct labelling of the gland contents. Raman spectroscopy documented the presence of β‐chitin in both gland types of Spiophanes. The tubes of Spiophanes were found to have a grid‐like structure that seems to be built with this β‐chitin. Tests of tubes of Dipolydora quadrilobata (Spionidae) for chitin were negative. However, the results of our study provide strong evidence that Spiophanes species, O. fusiformis and probably also G. orestes produce chitin and supposedly use it for tube‐building. This implies that the production of chitin and its use as a constituent part of tube‐building is more widespread among polychaetes as yet known. The histochemical data presented in this study support previous assumptions inferring homology of parapodial glandular organs of Spionidae and Siboglinidae based on ultrastructure. Furthermore, transmission electron microscopy‐based evidence of secretory cells with nail‐headed microvilli in O. fusiformis suggests homology of parapodial grandular organs across annelids including Sipuncula. J. Morphol. 276:1433–1447, 2015. © 2015 Wiley Periodicals, Inc.