Phasmarhabditis bohemica n. sp. (Nematoda: Rhabditidae), a slug-parasitic nematode from the Czech Republic

Abstract

Phasmarhabditis bohemica n. sp. is described and illustrated from the body of Deroceras reticulatum from the village of Chelčice, the Czech Republic. Morphological and molecular data showed that the new isolate is close to other species of Phasmarhabditis, particularly P. californica and P. papillosa. Females are characterised by a body length of 2079 (1777-2222) μm and a long tapering tail with prominent papilliform phasmids located laterally in the mid-tail region. Males are 1683 (1515-1818) μm long. They have a peloderan bursa, with nine pairs of rays, 1/1/1/2/1/3, and a reflexed testis 495 (434-555) μm long. Dauer juveniles are thin, 553 (474-636) μm long, with prominent lateral fields consisting of two prominent ridges and three incisures. Small subunit (18S), ITS, and D2-D3 expansion segments of the large subunit of ribosomal DNA were used to analyse the phylogenetic relationships of sequenced species in Phasmarhabditis and other closely related species. Our preliminary observations suggest that the newly described species may be a facultative mollusc-parasitic nematode that is able to survive permanently in the saprobic phase on decaying organic matter. The ecology, morphology, and phylogenetic positions of P. bohemica n. sp. are discussed.

Development ofPhasmarhabditis hermaphrodita(and members of thePhasmarhabditisgenus) as new genetic model nematodes to study the genetic basis of parasitism

“…The genus Phasmarhabditis contains 11 species: P. hermaphrodita , P. apuliae , P. papillosa , P. neopapillosa , P. valida , P. nidrosiensis , P. californica , P. tawfiki , P. bonaquaense , P. bohemica and P. huizhouensis (Andrássy, 1983; Hooper et al , 1999; Azzam, 2003; Tandingan De Ley et al , 2014, 2016; Huang et al , 2015; Nermut et al , 2016a, b, 2017). Phasmarhabditis hermaphrodita and other Phasmarhabditis species have been isolated from slugs from around the world, including the UK (Wilson et al , 1993; this study), Germany (Schneider, 1859; Mengert, 1953), France (Maupas, 1900; Coupland, 1995), Iran (Karimi et al , 2003), Egypt (Azzam, 2003; Genena et al , 2011), Norway (Ross et al , 2016), Chile (France & Gerding, 2000), New Zealand (Wilson et al , 2012), South Africa (Ross et al , 2012; Pieterse et al , 2017a, b), China (Huang et al , 2015), Japan (Waki, 2017), Italy (Nermut et al , 2016a) and the Czech Republic (Nermut et al , 2010, 2016b, 2017), and P. californica has been found in the USA (Tandingan De Ley et al , 2016), Ireland (Carnaghi et al , 2017) and Wales (this study). From these studies it is apparent that members of the Phasmarhabditis genus have a cosmopolitan distribution and are very easy to isolate from gastropod hosts.…”

“…The majority of research on P. hermaphrodita has focused on optimizing application techniques in the field (see Rae et al , 2007), host range studies (Wilson et al , 1993; Grewal et al , 2003; Rae et al , 2009), taxonomic descriptions, and surveys charting abundance and diversity of Phasmarhabditis in various countries (Ross et al , 2012, 2016; Wilson et al , 2012; Tandingan De Ley et al , 2014, 2016; Nermut et al , 2016a, b, 2017). There are few details and no reported methods regarding how to keep this nematode under lab conditions, like C. elegans , and whether it could be amenable to genetic manipulation.…”

A Literature Review of Biological and Bio-Rational Control Strategies for Slugs: Current Research and Future Prospects

“…Moreover, international surveys have been conducted in Europe [7], Asia [43], North America [44], Australia [45] and Africa [46] to identify whether nematodes from other families are associated with molluscs as definitive hosts. Overall, it has been reported that nematode species belonging to the following eight families-Agfidae, Alaninematidae Alloionematidae, Angiostomatidae, Cosmocercidae, Diplogasteridae, Mermithidae and Rhabditidae used molluscs as definitive hosts [40,[46][47][48][49][50][51][52][53][54][55][56][57][58][59][60][61][62][63][64][65].…”

Ex vivo development of Phasmarhabditis spp. associated with terrestrial molluscs

“…Phasmarhabditis bohemica Nermuť, Půža, Mekete & Mráček was described in 2017 from D. reticulatum in the Czech Republic (Nermuť et al, 2017). The ability of this species to cause mortality in its hosts requires further investigation as no apparent mortality was caused under natural conditions, but high mortality of D. reticulatum was observed under laboratory conditions (Nermut' et al, 2017). In the description of this nematode it was reported that P. bohemica can complete its life cycle on decaying animal matter within several days when kept at 15°C (Nermut' et al, 2017).…”