Phasmarhabditis apuliae n. sp. (Nematoda: Rhabditidae), a new rhabditid nematode from milacid slugs

Abstract

A new nematode species belonging to the family Rhabditidae, genus Phasmarhabditis, was isolated in the city of Bari (strain BAR) and near the village Gravina (strain GRA) in Apulia, Italy, and is described herein as Phasmarhabditis apuliae n. sp. The original hosts were Milax sowerbyi and M. gagates. Females are 2623 (2262-2848) μm long with a long tapering tail. Prominent papilla-like phasmids are present. Males are 2096 (1898-2363) μm long. They have a peloderan bursa with nine pairs of rays arranged as 1 + 1 + 1 + 2 + 1 + 3. Each ray bears a single papilla. A non-paired papilla is located near the ventral appendage anterior to the cloacal aperture. Prominent papilla-like phasmids are situated close to the tail tip. Dauer juveniles have lateral fields formed from two prominent wide ridges and have three incisures. Phasmarhabditis apuliae n. sp. seems to be a facultative mollusc-parasitic nematode that is capable, in a similar manner to P. hermaphrodita, of long-term survival in the saprophytic phase on decaying organic matter. Ecology, morphology and phylogenetic relationships of Phasmarhabditis nematodes are discussed.

Phylogenetic evidence for the invasion of a commercialized European Phasmarhabditis hermaphrodita lineage into North America and New Zealand

“…P. californica, a species recently discovered in North America [55], grouped with Phasmarhabditis bonaquaense, consistent with previous nuclear rRNA results [54]. P. papillosa grouped with Phasmarhabditis apuliae, offering a third example of consistency between our mtDNA phylogeny and nuclear rRNA-based analyses [56]. We also note here the discovery of a nematode strain in Oregon (DL308) isolated from Deroceras reticulatum that strongly grouped with two other nematode strains (DF5056, EM434) that were isolated from earthworms [61].…”

“…The mtDNA phylogenetic framework presented in this study for Phasmarhabditis spp. (Fig 1) revealed numerous topological consistencies when compared to other recent phylogenetic analyses of this genus that relied on nuclear ribosomal RNA (rRNA) genes [54][55][56][57][58][59][60]. For example, our analysis identified P. huizhouensis as an early-diverging lineage that is genetically distinct from the other seven species from the genus analyzed here, a pattern consistent with previous analyses of 18S and 28S rRNA loci [57].…”

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

“…Phasmarhabditis species have been isolated from slugs from around the world including the U.K. (Wilson et al, 1993; this study), Germany (Schneider, 1859;Mengert, 1953), France (Coupland, 1995;Maupas, 1900), Iran (Karimi et al, 2003), Egypt (Azzam, 2003;Genena et al, 2011), Norway (Ross et al, 2015), 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), Czechoslovakia (Nermut et al, 2010;2016b,c) and P.…”

“…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.…”

Phasmarhabditis zhejiangensis sp. nov. (Nematoda: Rhabditidae), a new rhabditid nematode from Zhejiang, China

“…had been recorded, including P. hermaphrodita, P. neopapillosa, P. tawfiki, P. bonaquaense, P. californica, P. huizhouensis, P. apuliae, P. bohemica, P. meridionalis, P. safricana, P. papillosa, P. circassica and P. clausliiae [12][13][14][15][16][17][18][19][20][21][22][23][24][25].…”