Morphology and Morphogenesis of a Freshwater Ciliate, Epistylis chlorelligerum Shen, 1980 (Ciliophora, Peritrichia)

Abstract

An oligohalobic peritrichous ciliate, Epistylis chlorelligerum Shen, 1980, was collected from a ditch in Hangzhou, China. The morphology, oral infraciliature, and morphogenesis of the species were studied using living and protargol-impregnated specimens. Zooids of E. chlorelligerum are 160-230 × 50-60 μm in vivo, and characterized by green-colored endoplasm containing symbiotic algae. The oral infraciliature presents a well-developed filamentous reticulum linked to the circular fiber of the cytostome; the outer two rows of P3 extend adstomally over P1 and usually enfold it. During binary fission, one daughter cell inherits most part of the old buccal apparatus and the reorganized haplokinety and germinal kinety (Hk' and G'), and new buccal apparatus of the other daughter cell is mostly developed from the original germinal kinety (G) and haplokinety (Hk): new peniculi 2, 3 (2P2, 2P3), new haplokinety (2Hk), and new germinal kinety (2G) are formed from G, while the new peniculus 1 (2P1) and its peristomial extention (2Pk) originate from Hk. The epistomial membrane can be observed until the two sets of buccal apparatus begin to separate from each other.

Evolution of Variations in the Common Pattern of Stomatogenesis in Peritrich Ciliates: Evidence from a Comparative Study Including a New Description of Stomatogenesis in Pseudepistylis songi Peng et al.,

“…() and Wu et al. (), focusing on the large, colonial species Campanella umbellaria (Linnaeus, 1758) and Epistylis chlorelligerum Shen, 1980, were done with an improved method of silver staining with protargol and described differences in the details of stomatogenesis in these two species, supporting the hypothesis that most differences reported by previous investigators are probably genuine rather than the result of observational error.…”

“…; Wu et al. ). It is logical to assume that the latter pattern is plesiomorphic in peritrichs because it is found in the basal species C .…”

“…; Wu et al. ). Lom () observed that the infundibular and peristomial parts of 1Hk are formed in Telotrochidium sp.…”

“…; Wu et al. ). In three other peritrichs, 1Gk is formed from kinetosomes in part of the 1Hk near the mouth of the infundibulum [ Telotrochidium sp.…”

“…; Wu et al. ) described stomatogenesis in large, colonial species of peritrichs, but a total of eight articles is still an astonishingly small number in view of the large size of the subclass Peritrichia (more than 800 species described according to Foissner et al. ) and the diversity of morphotypes represented within it (Sun et al.…”