Redescription of Testudotaenia testudo (Magath, 1924) (Eucestoda: Proteocephalidea), a parasite of Apalone spinifera (Le Sueur) (Reptilia: Trionychidae) and Amia calva L. (Pisces: Amiidae) in North America and erection of the Testudotaeniinae n. subfam.

Abstract

Testudotaenia testudo (Magath, 1924) is redescribed from the intestine of the softshell turtle Apalone spinifera (Le Sueur) (Trionychidae) and the bowfin Amia calva Linnaeus (Amiidae) from Reelfoot Lake, Tennessee, United States. A new subfamily, the Testudotaeniinae, is erected. The new taxon differs from all proteocephalidean subfamilies in the position of the genital organs in relation to the longitudinal internal musculature, i.e. the testes are cortical, rarely medullary; the ovary is partly medullary, with cortical lobes; the vitelline follicles are mainly medullary, with some follicles in the cortex; and the uterus is cortical. A key to the subfamilies of the order Proteocephalidea Mola, 1928 is provided. The most characteristic features of T. testudo are the precocious uterine aperture, the presence of internal uterine pores (as previously described for Proteocephalus paraguayensis (Rudin, 1917)), the eggs laid unripe, the very long strobila (up to 970 mm), and the presence of an anterior circular musculature in the suckers, which is considered as a good differential character. Three other species were found in Amia calva: Proteocephalus perplexus La Rue, 1911, P. ambloplitis (Leidy, 1887) and a new, undescribed form. Sequences of the partial nuclear 28S rRNA gene of specimens of T. testudo from Apalone spinulifera and Amia calva confirm the conspecificity of samples from these two very distinct hosts, which may represent a capture phenomenon. As the subfamily Adenobrechmoinae Bursey, Goldberg & Kraus, 2006 and the genus Adenobrechmos Bursey, Goldberg & Kraus, 2006 are based on the presence of an apical organ, a character which reflects a rather common convergence, we consider the Adenobrechmoinae to be a junior synonym of the Proteocephalinae La Rue, 1911 and Adenobrechmos a junior synonym of Ophiotaenia La Rue, 1911. Adenobrechmos greeri Bursey, Goldberg & Kraus, 2006 thus becomes Ophiotaenia greeri (Bursey, Goldberg & Kraus, 2006) n. comb.

Orders out of chaos – molecular phylogenetics reveals the complexity of shark and stingray tapeworm relationships

“…This was true for multiple genera in both the Proteocephalidae (e.g., Scholz et al, 1999; de Chambrier, 2006; de Chambrier and de Chambrier, 2010; Ash et al, 2012; Rambeloson et al, 2012) and the Monticelliidae (e.g., Gil de Pertierra, 2002; Gil de Pertierra, 2005; de Chambrier et al, 2006; Scholz et al, 2008; Arredondo et al, 2013; Gil de Pertierra and de Chambrier, 2013). While promising, this feature requires more detailed study across genera in both families as SEM data are available only for more recently described taxa and a few exceptions may exist (e.g., possibly de Chambrier et al, 2009; Gil de Pertierra, 2009). Also worth noting is the fact that Acanthobothrium and Uncibilocularis species bear a dense covering of gladiate spinitriches restricted to the cephalic peduncle (sensu Caira et al, 1999), a region of the body immediately posterior to the scolex proper that may be homologous to the neck and/or proliferation zone.…”

A large 28S rDNA-based phylogeny confirms the limitations of established morphological characters for classification of proteocephalidean tapeworms (Platyhelminthes, Cestoda)

“…A few parasites from amphibians and turtles, as well as Proteocephalus perplexus La Rue, 1911 from bowfin ( Amia calva L., 1766), also belong to this large polytomy. de Chambrier et al (2009a) showed that Testudotaenia Freze, 1965 of the monotypic subfamily Testudotaeniinae was part of a North American clade of proteocephalid parasites of fishes despite its distinctive morphology. These results do not contradict this hypothesis although Testudotaenia ’s closest relatives cannot be inferred from the present tree.…”

“…At the morphological level, the difficulty of defining reliable informative characters has prevented the construction of a stable taxonomic arrangement of the group (Rego 1994, 1995). The traditionally accepted families Proteocephalidae and Monticelliidae have been abandoned, and the whole group has been split into a number of subfamilies and genera, including the type genus Proteocephalus Weinland, 1858, which are sometimes obviously artificial because of their lack of synapomorphies and diversity of life-history traits (see de Chambrier et al 2004c, 2009a). Molecular studies that have tried to resolve the proteocephalidean tree topology have largely been based on the variable domains (D1–D3) of the large nuclear ribosomal RNA subunit (28S rDNA), using increasingly larger datasets, i.e.…”

“…Additional molecular studies mostly considered questions at the specific/generic level [e.g. the Proteocephalus aggregate (Scholz et al 2007); African Proteocephalus (de Chambrier et al 2011); Testudotaenia Freze, 1965 (de Chambrier et al 2009a), Corallobothriinae (Rosas-Valdez et al 2004, Scholz et al 2011)] or employed only a very limited taxon sampling (e.g. Zehnder and de Chambrier 2000, Škeříková et al 2001, de Chambrier et al 2008, Scholz et al 2013).…”

Characterization and phylogenomics of the complete mitochondrial genome of the polyzoic cestode Gangesia oligonchis (Platyhelminthes: Onchoproteocephalidea)

“…Onchoproteocephalidean tapeworms, with a cosmopolitan distribution, represent a diverse group of parasites with 316 valid species in bony fish, lizard, snake and amphibian hosts (Caira et al , 2017), and 246 valid species in elasmobranch hosts (Caira et al , 2017). The traditionally accepted families Proteocephalidae and Monticelliidae have been abandoned, and the only family Protecephalidae has been split into a number of subfamilies and genera (de Chambrier et al ., 2009). 28S rDNA-based phylogeny suggests that most of the presently recognized subfamilies (and genera) appear to be non-monophyletic, and a deep systematic reorganization of the order is thus needed (de Chambrier et al , 2015).…”