Shorter Odontostyle Research Articles

Description of Calcaridorylaimus heynsi n. sp. (Nematoda: Dorylaimidae) from Potchefstroom, South Africa

Summary Calcaridorylaimus heynsi n. sp. is the second species of the genus to be described by both morphological and molecular techniques. Morphologically, it can be distinguished from all known species of Calcaridorylaimus by a combination of the following characters: presence of advulval ornamentations, short body (0.90-1.33 mm), slightly anteriorly positioned vulva (V = 47.6 (45.8-49.8)), short odontostyle in females and males (13.1 (11.5-14.5) μm and 13.5 (12.0-18.0) μm, respectively), number of supplements (2 + 9-11), short spicules when measured along the median line (40.4 (38-42) μm) and pore-like vulval opening. It is closest to C. sirgeli, especially in the presence of advulval ornamentations and the pore-like vulva. Phylogenetic analysis based on partial D2-D3 segment of 28S rDNA sequences showed that C. heynsi n. sp. is in a well-supported sister relation with Mesodorylaimus sp. in a clade with C. cignatus and Mesodorylaimus spp. In the Bayesian tree, using partial sequences 18S rDNA, M. japonicus was the closest taxon to the new species.

Morphological and molecular characterisation of Longidorus pinus sp. n. (Nematoda: Longidoridae) from China and a key to known species of Longidorus in China

SummaryLongidorus pinussp. n. from China is characterised by females 3.3-4.9 mm long; lip region 8-12 μm diam., distinctly offset by a constriction; amphidial fovea pocket-shaped without basal lobes; a short odontostyle (67-81 μm); anteriorly located guide ring (30-38 μm); and short and conoid tail (31-40 μm long, c = 84-138, c′ = 1.2-1.9), with one or two pairs of caudal pores on each side. Males were not found. Three developmental juvenile stages were identified, the first-stage juvenile with conoid tail (c′ = 2.4-2.9). The polytomous key codes for the new species are: A2(3), B1, C23, D4, E1, F2, G23, H23, I1, J2, K6. Molecular phylogenetic analyses based on SSU, D2-D3 of LSU, ITS1 and ITS2 rDNA sequences indicate thatL. pinussp. n. is closely related toL. hangzhouensis,L. asiaticus, andL. camelliae, all of which apparently share a common Asiatic geographic origin. In addition, a key for identification ofLongidorusfound in China, based on morphological characters of both female and first-stage juvenile, is provided.

Description of two new records of genus Longidorus (Nematoda: Dorylaimida) in China

Two new recorded species of genus Longidorus (L. pius and L. diadecturus) were recovered and collected from rhizosphere of deciduous trees in Hangzhou of Zhejiang Province and Wuhan of Hubei Province, China, respectively. Morphological identity was confirmed using the revised polytomous key of Loof & Chen, 1999. The codes for identifying the species of L. pius and L. diadecturus are A56-B4-C3-D1-E1-F3-G1-H1-I1 and A4-B23-C5-D3-F2-G2-H1-I1, respectively. L. pius was characterized by medium body size (L=4.7-6.3 mm), anterior region abruptly tapering with rounded lip continuous from body profile, odontostyle long (130-143 μm) and short rounded tail. Meanwhile, L. diadecturus could be distinguished by short body size (3.2-4.6 mm), short odontostyle (108-120 μm), posterior position of guide ring (33-38 μm), wide lip region and a relatively anterior vulva. Phylogenetically, the rDNA internal transcribed spacer 1 (ITS1) region of L. pius from China showed 99% supported clade with L. pius topotype (AM743178) from Macedonia, and the similar relationship was obtained in L. diadecturus from China with 99% well supported clade to L. diadecturus type population (AF511416) from Canada. In addition, the 28S region of L. diadecturus from China showed 99% supported clade with L. diadecturus type specimen (AY601584), whereas L. pius noticeably clustered to L. raskii (AJ549983) and Longidorus sp. FDL-2011 (FR775757). The two species, L. pius and L. diadecturus were recorded for the first time in China, and the morphological description and phylogenetic relationships of the given species were provided in this study.

Two species of Nygolaimidae (Nematoda, Dorylaimida) from waterbodies of Vietnam

Illustrated descriptions of two nematode species from the genus Aquatides Heyns, 1968, A. heynsi sp. n. and A. thornei (Schneider, 1937) found in freshwater bodies of Vietnam are given. A. heynsi sp. n. is similar to A. intermedius (de Man, 1880) and A. thornei (Schneider, 1937). It differs from the former species in a shorter odontostyle and comparatively longer prerectum in females. It differs from A. thornei in a longer body, comparatively shorter pharynx, longer odontostyle, and comparatively longer prerectum in females.

Two new species of free-living nematodes of the genus Dorylaimoides Thorne, Swanger, 1939 from fresh waterbodies of Vietnam

Illustrated descriptions are given of two new species of free-living nematodes of the genus Dorylaimoides found in small fresh waterbodies of Vietnam. D. curvicaudatus sp. n. is morphologically similar to D. singaporensis Ahmad, Mushtaq, 2004 and D. elongatus Husain, Khan, 1968, but it has a shorter tail, longer basal widening of pharynx, different length of female prerectum, and longer spicules in males. Morphologically, D. vietnamicus sp. n. is close to D. leptidus Timm, 1964 and D. elaboratus Siddigi, 1965 but differs from both of them by a shorter odontostyle, the size of its spicules, and a smaller number of supplements in males.

ДВА ВИДА СВОБОДНОЖИВУЩИХ НЕМАТОД ОТРЯДА DORYLAIMIDA PEARSE, 1942 (NEMATODA) ИЗ ПРЕСНЫХ ВОДОЕМОВ ВЬЕТНАМА

Illustrated description of two free-living nematodes Paractinolaimus cattienus sp. n., Labronemella papillata (Khan, Ahmad et Jairajpuri, 1995) comb. n. found in freshwater bodies of Vietnam is given. P. cattienus sp.n. differs from near species P. acuprus Khan, Ahmad, Jairajpuri, 1994 by the relatively thinner body, shorter tail, shorter Odontostyle, shorter spicules and presence of gap in supplementary row of males.

Calcaridorylaimus castaneae sp. n. (Nematoda, Dorylaimidae) from Bulgaria with an identification key to the species of the genus.

An unknown species belonging to the genusCalcaridorylaimus Andrássy, 1986 was collected from the litter of broadleaf forests dominated by Castanea sativa Mill. and mixed with Quercus daleshampii Ten. and Fagus sylvatica L. on Belasitsa Mountain, south-western Bulgaria. Calcaridorylaimus castaneae sp. n. is characterised by its long body (1.4–2.1 mm), lip region practically not offset, vulva transverse, short odontostyle (14.5–16 μm) and tail (75.5–110.5 μm, c=14.7–23.6; c’=2.9–4.4) in females and 38–46 μm long spicules with small spur before their distant end in males. It is most similar to C. andrassyi Ahmad & Shaheen, 2004, but differs in having transverse vs pore-like vulva and shorter spicules (38–46 μm vs 52–57 μm). An identification key to the species of the genus Calcaridorylaimus is proposed. Phylogenetic analyses were performed on 18S and D2-D3 expansion domains of 28S rRNA genes by Neighbor-Joining, Maximum Likelihood and Bayesian Inference methods. The phylograms inferred from 18S sequences showed closest relationships of the new species with some species belonging to the genus Mesodorylaimus. However, insufficient molecular data for members of both genera do not allow the phylogenetic relationships of Calcaridorylaimus and the new species described herein to be elucidated.

ДВА НОВЫХ ВИДА РОДА LAIMYDORUS SIDDIQI, 1969 (NEMATODA, DORYLAIMIDA) ИЗ МЕЛКИХ ПРЕСНОВОДНЫХ ВОДОЕМОВ ВО ВЬЕТНАМЕ

Two new species of free-living nematodes of the genus Laimydorus (L. gigas sp. nov. and L. tenuis sp. nov.), found in the sediments of small freshwater bodies in Vietnam, are described and illustrated. Laimydorus gigas sp. nov. is similar to L. distinctus Dey, Baqri, 1986 and L. elephas Andrassy, 1988. From the former species it differs in the longer tail in females, the shorter spicules and greater number of supplements in males. From L. elephas it differs in the thinner cuticle, thinner body, comparatively longer odontostyle and comparatively longer prerectum in females. Laimydorus tenuis sp. nov. is similar to L. merogaster (Steiner, 1916) and L. pinguis Andrassy, 1988. From the former species it differs in the thinner cuticle, thinner body, shorter odontostyle, shorter spicules and smaller number of supplements in males. From L. pinguis it differs in the thinner body, shorter tail in females, another position of vulva and comparatively longer prerectum in females.

A report on <i>Aporcelaimellus</i> sp (Nematoda: Dorylaimidae) from cultivated crops in Rajshahi University Campus

100 nematode specimens under the genus Aporcelaimellus was identified from different cultivated crops. The genus is within the family Dorylaimidae, and contains robust animals of 0.8 to 3.5 mm body length. The specimen having the medium-sized body, short odontostyle, unsclerotized vulva, conical, dorsally not concave tail with distinctly separated layers of terminal cuticle. Aporcelaimellus prevalence was the highest in banana (80%) and the lowest was in mulberry (20%) during sampling periods. The diagnostic morphology of this nematode was slender vulva lips, thick vagina, and with long anal body with sharply pointed tail.DOI: http://dx.doi.org/10.3329/ujzru.v30i0.10752Univ. j. zool. Rajshahi Univ. Vol. 30, 2011 pp. 45-48

Prodorylaimus filamentus sp. n. and Eutobrilus longicaudatoides sp. n. (Nematoda) from Lake Baikal, Russia

Two nematode species found in Lake Baikal, Russia are described. Prodorylaimus filamentus sp. n. is morphologically close to P. longicaudatoides Altherr, 1968 and P. kralli Tsalolikhin, 1975. The new species can be separated from P. longicaudatoides by the longer body (L = 4.89–6.06 mm versus L = 2.0–3.5 mm), relatively longer tail (c′ = 18.4–25.0 versus c′ = 14–18), longer odontostyle (60–65 µm long versus 32–37 µm long), presence of double and wide guiding ring and longer spicules (89–90 µm long versus 70–78 µm long). It can also be separated from P. kralli by the longer tail (c = 4.3– 6.0, c’ = 18.4–25.0 versus c = 7.0–8.0, c′ = 11–16), lower “vulva-anus to tail length” ratio (1.6–2.2 versus 2.5–3.0), shorter odontostyle (60–65 µm long versus 75–80 µm long). Eutobrilus longicaudatoides sp. n. is closely related to E. anguiculus Tsalolikhin, 1977, but is clearly distinct in the shorter outer labial setae (9–10 µm long or 45–52% of the labial region diameter versus 15–20 µm long or 50–60 % of the labial region diameter), longer tail (males, c = 5.3–5.5, c’ = 11.4–11.8, females, c = 4.5–6.3, c′ = 15.1–16.7, versus males, c = 7.4–10.4, c′ = 8–9, females, c = 5.0–7.7, c′ = 10–12), smaller number of supplements (5 versus 6) and shorter spicules (47–53 µm long versus 66–68 µm long).

Two new species of dorylaimids (Nematoda and Dorylaimida) from Lake Baikal

Illustrated descriptions are given of two species of free-living nematodes new to science, Arctidorylaimus parvulus and Eudorylaimus sedatus, found in the littoral zone of southwestern Lake Baikal. A. parvulus, sp. n., differs from A. kurenkovi Gagarin, 2002, in its shorter body, absence of longitudinal cuticular ridges, shorter spicules, smaller number of precloacal supplements, and relatively short prerectum. E. sedates sp. n. is morphologically similar to E. spongiophilus Batalova, 1983, but smaller, has shorter odontostyle and odontophore, and longer tail and prerectum. An identification key to the valid species of the genus Arctidorylaimus is given.

Rare and little-known species of free-living nematodes Eudorylaimus lotharingiae Altherr, 1963 (Nematoda, Dorylaimida)

Studies of the bottom fauna of the Selenga River have identified a rare species of free-living nematodes Eudorylaimus lotharingiae Altherr, 1963. An illustrated description of females and an unknown male of this species is presented. Morphologically, E. lotharingiae is close to the Baikal species E. spongiophylus Batalova, 1963, but it differs in the lateral annulation of its subcuticular layer, wider lip region, shorter odontostyle, and longer prerectum.

Two New Species Of Aporcelaimellus (Nematoda: Dorylaimida) From The Americas

This paper provides the descriptions and illustrations of two new species of the nematode genus Aporcelaimellus (family Aporcelaimidae). Aporcelaimellus salsus sp. n. from the United States is characterized by the medium-sized body, short odontostyle, unsclerotized vulva, conical, dorsally not concave tail with distinctly separated layers of terminal cuticle. Aporcelaimellus acaudatus sp. n. from Ecuador is distinguished by the large body, sclerotized vulva and especially by the exceedingly short and blunt tail with strongly thickened inner layer of terminal cuticle.

Systematic Study of Dorylaimida from Korea : 4. Four New Species of Dorylaimida from Korea

Four new species of Dorylaimida from Korea are described and illustrated. Belondira pugwiensis n. sp. is 1.7–1.9 mm long, b = 3.3–4.2, c = 58.1–65.8, V = 35–37, odontostyle = 6.5–7.3 μm and characterized by having a prominent spindle-shaped valve area in the anterior part of oesophagus and long expanded part of oesophagus, occupying 68–70% of total oesophageal length. Lindseyus juwangens sp. n. is 3.5–4.1 mm long, b = 13.3–14.5, c = 11.6, V = 40–40.3, odontostyle = 6.6–7.4 μm and characterized by having a slender body, short odontostyle and longer spicule. Prodorylaimus donghagens sp. n. is 1.7–2.1 mm long, b = 3.9–4.6, c = 5.8–6.3, V = 47–49, odontostyle = 29.2–32 μm and characterized by continuous, truncated lip region and ventrally hooked tail end. Prodorylaimus taebekensis sp. n. is 1.2–1.5 mm long; b = 4.2, c = 5–6, V = 43.3–47.2, odontostyle = 16–19 μm, spicule = 35–46 μm and ventromedian supplements = 5–6 and characterized with slightly set off lip region and long filiform tail with ventrally hooked terminus.

Systematic Study of Dorylaimida from Korea: 3. Three New and Four Known Species of Dorylaimida from Korea

Three new and four known species of dorylaim nematodes are described and illustrated. Lenonchium asterocaudatum n. sp. is 2.5–3.1 mm long; c=17.3–25.1; odontostyle=16–19 μm and resembles Lenonohium oryzae Siddiqi, 1965 and Lenonohium macrodorum Ahmad and Jairajpuri, 1988 but differs from the former in the presence of 4–5 projections (mucronate) or starshaped structures on the tail tip in both sexes and from the latter in having a shorter odontostyle (33–35 μm in L. macrodorum). Paravulvus kyeryongensis n. sp. is 0.9–1.1 mm long; c=49.5–67; odontostyle=5.8–7.3 μm and comes close to Paravulvus papillatus and Paravulvus teres but differs from P. papillatus in having a longer and slender body (L=1.31–1.49 mm; a=41–46 vs. L=0.94–1.22 mm; a=30–36); shorter odontostyle (6–7 μm vs. 8–9 μm) and lesser ‘Vrsquo; value (48–49 vs 51–53); from P. teres differs in having longer prerectum (38–54 μm vs. 28–36 μm). Proleptonchus parkerus n. sp. is 1.3–1.4 mm long; c=82.3; odontostyle=5.1–5.8 μm and comes close to Proleptonchus indicus, Proleptonchus saccatus, Proleptonchus lacihoveyensis, and Proleptonchus johnsoni because of the presence of post uterine sac with rudimentary oviduct and ovary, but differs from all of them in having a prerectal chamber before it joins rectum. The new species also differs from P. saccatus in having non-duplex amphids and a much smaller basal bulb (33.5–40.1 μm vs 51.2–54.4 μm); from P. johnsoni in having smaller posterior uterine sac (4 vs. 2 body width); from P. lacihoveyensis in having non-duplex amphids. P. indicus, the most close to new species but have a smaller posterior uterine sac (55.8–75.6 μm vs 94 μm). Aquatides intermedius, Axonchium asacculum, Axonchium vaginatum and Paravulvus papillatus were recorded for the first time from Korea.

Systematic Study of Dorylaimida from Korea: 2. Description of Two New and Two Known Species of the Family Actinolaimidae from Korea

Two known and two new species of the family Actinolaimidae (Nematoda: Dorylaimida) (Thorne, 1939) Meyl, 1960 are described and illustrated. Afractinolaimus zairensis (Baqri et al., 1973) Jairajpuri & Khan, 1992 and Egtitus andhricus Khan and Jairajpuri, 1994 were reported for the first time from Korea. Paractinolaimoides hawangensis n. sp. is 2.9–3.6 mm long, b=3.9–4.5; c=8.8; spicules=73.8–77.4 μm) and differs from the only known species Paractinolaimoides unicus Khan et al., 1994 in having longer body, odontostyle, odontophore, prerectum, spicules and greater number of ventromedian supplements (L=1.9–2.1 mm; odontostyle=21–24 μm; odontophore= 24–26 μm; prerectum=87–105 μm; spicule=54–57 μm and ventromedian supplements= 10–12 in P. unicus). Westindicus cheongsongensis n. sp. is 2.3–2.6 mm long; b=4.2–4.6; c=8.1–9.7; odontostyle=25.2–27.0 μm; spicules=61–65 μm and differs from all known species of the genus in having greater number of ventromedian supplements (15–17 in Westindicus cheongsongensis n. sp. vs. 5–7 in Westindicus brachycephalus, 11 in Westindicus keralaensis and 8 in Westindicus rapax). This new cheongsongensis further differs from Westindicus rapax Hunt, 1978 in having a shorter odontostyle and a lesser ‘V’ value (odontostyle=27–32 μm and V=49–52 in W. rapax); from W. keralaensis Khan et al., 1994 in having longer filiform tail and from W. brachycephalus Thorn, 1967 in possessing longer odontostyle (c=20 and odntostyle=15 μm in W. keralaensis and W. brachycephalus, respectively).

Description of Chitwoodiellus Gracilis Gen. N., Sp. N. From Spain, With a Study On Its Morphometric Differentiation From Chitwoodius Furstenberg & Heyns, 1966 (Nematoda: Tylencholaimidae)

Chitwoodiellus gen. n. is described from a new and three previously known species. It is close to the genera Chitwoodius Furstenberg & Heyns, 1966, Tylencholaimus de Man, 1880 and Xenonchium Siddiqi & Khan, 1964 (subfamily Tylencholaiminae). It differs from Chitwoodius in head shape, presence of perioral pieces, shorter odontostyle, existence of a sclerotized thickened area where the odontophore joins the pharyngeal lumen, guiding ring nearer the anterior end, vagina not fringed and the morphology of the vulva. The new genus can be distinguished from Tylencholaimus by the longer and thinner odontostyle, different morphology of the odontophore and the existence of a sclerotized thickened area surrounding the junction between the odontophore and the pharyngeal lumen. From Xenonchium it differs by the longer and thinner odontostyle, existence of a sclerotized thickened area where the odontophore joins the pharyngeal lumen, different morphology of the vulva and the female genital system being didelphic-amphidelphic. Chitwoodiellus gracilis gen. n., sp. n. is described and illustrated from an undisturbed area in central Spain. Three previously known Chitwoodius species are transferred to the new genus: C. fuscus (Sauer, 1969) n. comb., C. heynsi (Pena Santiago. 1991) n. comb. and C. parafuscus (Pena Santiago, 1991) n. comb. Univariate and multivariate statistical analysis were carried out with species of Chitwoodius and Chitwoodiellus gen. n. in order to confirm their separation into two different groups. The results obtained support the proposal of the new genus.

A New Species of the Rare Nematode Genus Trachypleurosum Andrassy, 1959 (Nematoda: Actinolaimidae) From India

Trachypleurosum indicum n. sp. is described and illustrated. It has a 1.49-1.97 mm long body, a = 36-43; b = 3.7-4.7; c = 11-15; V= 49-54; odontostyle = 18-21 μm; spicules = 37-45 μm and is characterized by rugose cheilostomal walls and a short odontostyle.

Enchodel Us Morgensis N. Sp. and Considerations On the Genus Rhyssocolpus Andrassy, 1971 (Nematoda: Dorylaimidae)

Enchodelus morgensis n. sp. is described from the banks of Morges River, Switzerland. It is a small species with short odontostyle and conoid-arcuate tail in both sexes. It keys to E. brevidentatus Thorne, 1939 but is smaller, the hyaline part of the tail is much longer, and males are numerous. The genus Rhyssocolpus Andrassy, 1971 is synonymized with Enchodelus, since the main differentiating character, the wrinkled advulvar cuticle, is considered of no more than specific value. As a consequence, E. arcticus (Ebsary, 1984) is renamed E. ebsaryi because of homonymy.

Redescription and distribution of Xiphinema rivesi Dalmasso, 1969 and Xiphinema americanum Cobb, 1913 in Canada with a description of Xiphinema occiduum n. sp. (Nematoda: Longidoridae)

Xiphinema rivesi and Xiphinema americanum are redescribed and illustrated from several eastern Canadian localities. Xiphinema occiduum n. sp. is described and illustrated from western Canada. The new species is most closely related to X. utahense but differs by the shorter odontostyle, greater J length and width, more anterior guiding ring, smaller a value and less elongate tail. The distribution and hosts of each species in Canada are also provided.