Apofrontonia dohrni sp. n. and the phylogenetic relationships within Peniculia (Protista, Ciliophora, Oligohymenophorea)

Abstract: Apofrontonia dohrni, a new peniculine ciliate, was discovered in a slightly brackish water sample from Mediterranean coastline puddle in Naples, Italy. Its morphology was studied in vivo, in silver- and Feulgen-stained preparations, as well as at the scanning electron microscope; 18S rRNA gene sequence was also determined. The species is characterized by a medium cell size (118 x 61 mu m - fixed cell) and an oval-extended body, flattened dorsoventrally; a very long sausage-like macronucleus rolled up into almost a ring; a comparatively large compact micronucleus; relatively small number of vestibular kineties (4) and a peculiar structure of 3 peniculi, consisting of 5-6, 4-5 and 3 ciliary rows, respectively. The ciliate always has about 20 contractile vacuoles distributed beneath its entire body surface. Using these features, A. dohrni, definitely, can be easily discriminated from the two other species of the genus: Apofrontonia lametschwandtneri and Apofrontonia obtusa. T...