| Abstrakt: |
Chromidinaspp. are enigmatic apostome ciliates (Oligohymenophorea, Opalinopsidae) that parasitise the renal and pancreatic appendages of cephalopods. Only four species have been described, among which only three have been formally named. No DNA sequence has been reported so far. To investigate Chromidinaspp. diversity, we sampled cephalopods in the Mediterranean Sea off Tunis, Tunisia, and identified two distinct Chromidinaspp. in two different host species: Loligo vulgarisand Sepia officinalis. From haematoxylin-stained slides, we described morphological traits for these parasitic species and compared them to previous descriptions. We also re-described the morphology of Chromidina elegans(Foettinger, 1881) from Chatton and Lwoff’s original materials and designated a neohapantotype and paraneohapantotypes for this species. We describe a new species, Chromidina chattoniSouidenne, Florent and Grellier n. sp., found in L. vulgarisoff Tunisia, and evidence for a probable novel species, found in S. officinalisoff Tunisia, although this latter species presents similarities to some morphological stages previously described for Chromidina corteziHochberg, 1971. We amplified, for the first time, an 18S rDNA marker for these two Chromidinaspecies. Phylogenetic analysis supports the association of Chromidinawithin apostome ciliates. Genetic distance analysis between 18S rDNA sequences of representative apostomes indicates Pseudocolliniaas the most closely related genus to Chromidina. |
