Central European parasitic flatworms of the family Renicolidae Dollfus, 1939 (Trematoda: Plagiorchiida): molecular and comparative morphological analysis rejects the synonymization ofRenicola pinguiscomplex suggested by Odening

Abstract

The Renicolidae are digenean parasites of piscivorous and molluscivorous birds. Although they exhibit few morphological autapomorphies and are highly variable, the numerous suggested re-classifications within the family have never been supported by any molecular analyses. We address the possible synonymization of species within the Renicola pinguis complex suggested previously by Odening. We provide and analyse sequences of two nuclear (ITS2, 28S rDNA) and two mitochondrial (CO1, ND1) DNA loci of central European species of the Renicolidae, namely Renicola lari, Renicola pinguis and Renicola sternae sp. n., and we also provide first sequences of Renicola sloanei. The combined molecular and comparative morphological analysis confirms the previously questioned validity of the three Renicola spp. of highly similar morphology, which display strict niche separation in terms of host specificity and selectivity. We identify two previously unreported clades within the genus Renicola; however, only one of them is supported by the analysis of adult worms. We also provide comparative measurements of the three examined closely related central European renicolids, and describe the newly proposed tern-specialized species Renicola sternae sp. n., which was previously repeatedly misidentified as Renicola paraquinta. Based on the extensive dataset collected in 1962-2015, we update the host spectrum of Renicolidae parasitizing central European birds (Renicola bretensis, R. lari, Renicola mediovitellata, R. pinguis, Renicola secunda and R. sternae sp. n.) and discuss their host-specific prevalence and intensity of infections.

Molecular identification and histological aspects of Renicola sloanei (Digenea: Renicolidae) in Puffinus puffinus (Procellariiformes): a first record

“…In the ITS2 region, the high nt similarity among R. sloanei strains from P. puffinus of this study (100%) may be due to the parasitism of the same species as the definitive host. In addition, the strains presented less nt similarity (95.9%) with the other R. sloanei strains described previously by Heneberg et al (2016) in S. demersus.…”

“…According to the morphological findings described by Wright (1956) and the phylogenetic analysis performed in this study, it can be suggested that C. pythionike is a metacercariae of R. sloanei, since it has the close nt similarity with R. sloanei of P. puffinus (96.6%) (described herein) and with R. sloanei of S. demersus (96.2%) (HENEBERG et al, 2016). In addition, C. pythionike, when compared to other renicolid strains, showed a reduced nt similarity with R. sternae (69.2%), R. lari (68.4%), and R. pinguins (74.6%).…”

“…It is also important to note that eggs from R. sloanei present smaller dimensions than R. lari from C. ridibundus and Renicola sp. from L. dominicanus (WRIGHT, 1954b;HENEBERG et al, 2016) (Table 2). The dimensions of the eggs differ between the renicolids species (WRIGHT, 1956).…”

“…The sequences from the digeneans of P. puffinus in this study showed 100% of nt similarity to each other and 95.9%, 96.6%, and 87.3% with Renicola sloanei (accession number: KU563710; HENEBERG et al, 2016), Cercaria pythionike (accession number: DQ489707), and C. doricha (accession number: DQ489708) strains, respectively. The C. pythionike strain also exhibited a close molecular similarity with R. sloanei (96.2%) (accession number: KU563710;HENEBERG et al, 2016). When compared with other species of the genus Renicola (R. lari, R. pinguins, and R. sternae; HENEBERG et al, 2016) available in GenBank, the two nt sequences of R. sloanei of P. puffinus exhibited lower nt similarity (68.6%, 74.2%, and 68.8%, respectively).…”

Molecular systematics of the digenean community parasitising the cerithiid gastropod Clypeomorus batillariaeformis Habe & Kusage on the Great Barrier Reef

“…3) demonstrated that the species sequenced in this study is a member of the genus Renicola. Although 28S sequence data have been provided for three fully identified species of the genus Renicola [49], these sequences fail to align properly with those produced for renicolids in this or any other study [27,[50][51][52][53]. Because of this, we did not incorporate these 28S rDNA data into our phylogenetic analyses.…”