Abstract
During an investigation on freshwater peritrichs, a new colonial sessilid ciliate,
Campanella sinica
n. sp., was isolated from aquatic plants in an artificial freshwater pond in Qingdao, China. Specimen observations of this species were performed both
in vivo
and using silver staining.
C. sinica
n. sp. is characterized by the appearance of the mature colony, which is up to 2 cm high and contains more than 1,000 zooids, the asymmetric horn-shaped zooids, strongly everted and multi-layered peristomial lip, the slightly convex peristomial disc, and the well-developed haplokinety and polykinety, which make more than four circuits of the peristome before descending into the infundibulum. The small subunit ribosomal DNA (SSU rDNA), 5.8s rDNA and its flank internal transcribed spacers (ITS1-5.8s rDNA-ITS2), and large subunit ribosomal DNA (LSU rDNA) are sequenced and used for phylogenetic analyses which reveal that the family Epistylididae Kahl, 1933 is non-monophyletic whereas the genus
Campanella
is monophyletic and nests within the basal clade of the sessilids. The integrative results support the assertion that the genus
Campanella
represents a separate lineage from other epistylidids, suggesting a further revision of the family Epistylididae is needed. We revise
Campanella
including the transfer into this genus of a taxon formerly assigned to
Epistylis
, which we raise to species rank, i.e.,
Campanella ovata
(
Nenninger, 1948
) n. grad. & n. comb. (original combination
Epistylis purneri
f.
ovata
Nenninger, 1948
). In addition, we provide a key to the identification of the species of
Campanella
.