A survey to collect soil nematodes with potential to controlCeratitis capitataflies was carried out in different locations in Tunisia. Several nematode isolates were recovered, laboratory colonies were established, and their taxonomic identities were determined based on molecular methods. Among all the recovered nematode isolates, two of them,Oscheius tipulaeTC2 and OC2, were evaluated for their capacity to controlC.capitataflies and for their ability to kill and reproduce onGalleria mellonellalarvae. Our results show a great potential of these two isolates as biocontrol agents as they killC.capitataeggs and pupae and interfere with the metamorphosis ofC.capitatalarvae. More specifically, TC2 and OC2 nematodes killed 39 and 31% ofC.capitataeggs, respectively, impaired the metamorphosis of up to 77% and up to 67% ofC.capitatalarvae, respectively, and killed up to 66% and up to 58% ofC.capitatapupae, respectively. The efficacy of TC2 and OC2 nematodes was particularly high onC.capitatapupae, and significant insect mortalities were observed even at concentrations of 1 and 5 nematodes/pupae, respectively. We also found that TC2 and OC2 nematodes efficiently kill and reproduce inG.mellonellalarvae, suggesting that these insects could be used for mass-multiplication of these nematodes. These results reveal the potential ofO.tipulaeto complement integrated pest management programs againstC.capitataflies.

Background: Nematodes of the genus Heterorhabditis are important biocontrol agents as they form a lethal combination with their symbiotic Photorhabdus bacteria against agricultural insect pests. This study describes a new species of Heterorhabditis. Methods: Six Heterorhabditis nematode populations were recovered from agricultural soils in Jammu and Kashmir, India. An initial examination using mitochondrial and nuclear genes showed that they belong to a new species. To describe this new species, a variety of analyses were conducted, including reconstructing phylogenetic relationships based on multiple genes, characterizing the nematodes at the morphological and morphometric levels, performing self-crossing and cross-hybridization experiments, and isolating and characterizing their symbiotic bacteria. Results: The newly discovered species, Heterorhabditis casmirica n. sp., shares 94% mitochondrial cytochrome C oxidase subunit I gene (COI) sequence identity with Heterorhabditis bacteriophora and Heterorhabditis ruandica, and 93% with Heterorhabditis zacatecana. Morphologically, it differs from H. bacteriophora in its infective juvenile phasmids (present vs. inconspicuous) and bacterial pouch visibility in the ventricular portion of the intestine (invisible vs. visible); genital papilla 1 (GP1) position (at manubrium level vs. more anterior), and in its b ratio (body length/neck length), c ratio (tail length/bulb width), and D% [(excretory pore/neck length) × 100]. Other morphological differences include anterior end to the nerve ring distance (77–100 vs. 121–130 μm), V% [(anterior end of vulva/body length) × 100] (46–57 vs. 41–47) in hermaphroditic females; rectum size (slightly longer than the anal body diameter vs. about three times longer), phasmids (smaller vs. inconspicuous), body length (0.13–2.0 vs. 0.32–0.39 mm), body diameter (73–150 vs. 160–220 μm), anterior end to the excretory pore distance (135–157 vs. 174–214 μm), and demanian ratios in amphimictic females. Morphological differences with H. ruandica and H. zacatecana were also observed. Furthermore, H. casmirica n. sp. did not mate or produce fertile progeny with other Heterorhabditis nematodes reported from India. It was also discovered that H. casmirica n. sp. is associated with 'Photorhabdus laumondii subsp. clarkei symbiotic bacteria. Conclusions: The discovery of H. casmirica n. sp. provides novel insights into the diversity and evolution of Heterorhabditis nematodes and their symbiotic bacteria. This new species adds to the catalog of entomopathogenic nematodes in India. Graphical

The morphology of dorylaimid spicules is richer than usually conceived and shows interesting interspecific variations that have not received much attention. New ideas are proposed to describe these structures, including a delimitation or definition of their parts and a series of morphometrics, either (absolute) measurements or ratios. Three descriptive examples are presented. Several morphological characters (head shape, development of the ventral hump,etc.) and a number of morphometric features (total and relative lengths, relative size of the median piece, terminal tip width,etc.) are especially useful for species characterisation and comparative purposes.

Three new and one known species of the genus Aporcelaimellus with simple uterus and typical caudal region, mainly col-lected in natural areas of southeastern Iberian Peninsula, are studied, including descriptions, measurements, line illustra-tions and LM pictures. Aporcelaimellus baeticus sp. n. is characterized by a body length of 1.96–2.95 mm, lip region offset by constriction and 17–20 μm broad, odontostyle 17–22 μm long, neck 510–635 μm long, pharyngeal expansion 250–335 μm long, a dorsal cell mass at level of anterior end of intestine, uterus 60–150 μm long or 0.9–1.7 times the corresponding body diameter, vulva transverse (V = 48–54), tail convex conoid with broadly rounded terminus (30–46 μm, c = 47–80, c’ = 0.7–1.1), spicules 99–103 μm long, and 18–21 irregularly spaced ventromedian supplements which lack hiatus. Apor-celaimellus brevicaudatus sp. n. is characterized by a body length of 1.54–2.14 mm long, lip region offset by a more or less distinct constriction and 14–16 μm broad, odontostyle 13–15 μm long, neck 512 μm long, pharyngeal expansion 255 μm long, uterus 39–57 μm long or 0.9–1.0 times the corresponding body diameter, V = 50–55, tail short and rounded to hemispherical (24–27 μm, c = 66–82, c’ = 0.6–0.7) with inner core hardly reaching the middle of tail length, and male unknown. Aporcelaimellus rotundus sp. n. is characterized by its body 2.01–2.58 mm long, lip region offset by constriction and 19–20 μm broad, odontostyle 22–23 μm long, neck 455–579 μm long, pharyngeal expansion 226–316 μm long, a dis-tinct dorsal cell mass present at cardia level, uterus 28–74 μm long or 0.5–0.9 times the corresponding body diameter, V = 47–52, female tail short and conoid to rounded (27–33 μm, c = 64–90, c’ = 0.7–0.9), and males unknown. New data, including SEM pictures, sequences and taxonomic comments, are provided for A. waenga.