Noctuidonema Dibolia N. Sp. (Aphelenchida: Acugutturidae), an Ectoparasite of the Moth Mocis Latipes (Lepidoptera: Noctuidae) 1
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Journal of Nematology 27(3):387-394. 1995. © The Society of Nematologists 1995. Noctuidonema dibolia n. sp. (Aphelenchida: Acugutturidae), an Ectoparasite of the moth Mocis latipes (Lepidoptera: Noctuidae) 1 O. G. MARTI, JR, AND C, E. ROGERS 2 Abstract: Noctuidonema dibolia n. sp., an ectoparasite of adults of the noctuid moth Mocis latipes (Guen6e) is described. The differentiating characters are a club-shaped body with a subterminal vulva in the female, spicules with a reduced matrix and sheath and closely apposed dorsal and ventral arms in the male, very long styler and conus, moderately prominent stylet knobs, a bluntly rounded head, and a large renette cell in both sexes. Lateral fields, rectum, anus, bursa, and gubernaculum are absent. Noctuidonema dibolia differs from the other species of the subfamily Noc- tuidonematinae in the size and robustness of the body, the length of the stylet and conus, the length of the tail, and the shape of the spicules. Key words: ectoparasite, insect parasite, Lepidoptera, Mocis latipes, moth, nematode, Noctuidae, Noctuidonema dibolia n. sp., taxonomy. Surveys of Lepidoptera in French Gui- MATERIALS AND METHODS ana (9,12), the tropical Americas (11,12), Mocis latipes adults were collected from and the southeastern United States (10) 1991-93 in a walk-in ultraviolet light trap documented the widespread occurrence of located on a research farm near Tifton, an ectoparasitic nematode, Noctuidonema Georgia. The external surfaces of the guyanense Remillet and Silvain, particularly moth abdomens were examined with a ste- among moths in the family Noctuidae. reoscopic microscope for the presence of Noctuidonema Remillet and Silvain is of in- nematodes. Infested moths were placed terest because it is one of only a few known into a 15-ml cup containing 2 ml of water metazoan parasites of adult moths (3) and plus a few drops of Tween 80 (polyoxyeth- is currently under study as a possible bio- ylenesorbitan monooleate) and shaken for logical control agent for the fall armyworm a few seconds to dislodge nematodes. moth, Spodoptera frugiperda (J. E. Smith), a Nematodes were concentrated by sedi- serious pest of corn, sorghum, and pasture mentation in distilled water, examined live grasses (12,13). or killed in hot water (60 C), and fixed Mocis latipes (Guen6e), whose larvae are and stored in TAF (Triethanolamine-For- known as striped grass loopers, is prima- malin-Water 7:2:91) (4) until processed rily a pest of pasture grasses (5,12). Speci- through an alcohol series to glycerin. The mens of the genus Noctuidonema, collected nematodes were then mounted on glass from M. latipes in Tift County, Georgia, slides and examined with differential in- were examined and found to differ from terference contrast or phase contrast op- N. guyanense, Vampyronema daptria (Ander- tics. Drawings are based on microscopic son and Laumond) (2,7), and the related examination and photographs of living as genus Acugutturus Hunt (6), and are here well as processed specimens. Values in the described as a new species, N. dibolia. The text are expressed as: range in p~m (mean specific name 'dibolia' is taken from Greek in txm -+ SD). (= pointed at both ends). SYSTEMATICS Received for publication 19 September 1994. i Mention of a trade name, warranty, proprietary product, Noctuidonema dibolia n. sp. or vendor does not constitute an endorsement of a product and does not imply its approval to the exclusion of other (Figs. 1A-C;2A-E) products or vendors that may also be suitable. Microbiologist and Research Entomologist, USDA, ARS, Holotype ~emale): Length = 522 Ixm; Insect Biology and Population Management Research Labo- maximum width = 57 Ixm; width at vulva ratory, P.O. Box 748, Georgia Coastal Plain Experiment Sta- tion, Tifton, GA 31793. = 44 i~m; anterior end to excretory pore 387 ..................................... [I ........................... I ..................... I 388 Journal of Nematology, Volume 27, No. 3, September 1995 = 22 ixm; anterior end to nerve ring = 16 ~m; anterior end to excretory pore = 137 Ixm; stylet length = 108 ~m; styler co- 25 >m; anterior end to nerve ring = 118 nus length = 91 p.m; metacorpus length ~m; stylet length = 89 p.m; stylet conus = 28 Ixm; metacorpus width = 23 ~xm; length = 73 Ixm; metacorpus length = 28 ovary length = 225 p.m; tail length = 66 Ixm; metacorpus width = 20 p~m; testis /~m. length = 225 p~m; tail length = 8 jxm; Allo~pe (male): Length = 464 p~m; max- spicule length = 44 Ixm; rostrum length = imum width = 41 ixm; width at cloaca = 12 ~xm. 7( 5( 2 / Flo. 1. Noctuidonemadibolia n. sp. A) Female. B) Male. C) Spicules. Noctuidonema dibolia n. sp.: Marti and Rogers 389 a ~ C /V ~ ii ', 60um A 10urn B 10um C ,25urn D 30um E FIG. 2. Noctuidonemadibolia n. sp. A) Fourth-stagejuvenile. B) Head end of female. C) Head end of male. D) Newly hatched second-stagejuvenile. E) Embryonatedegg with fully formed juvenile. Paratypes: Measurements of 39 females 0.2) at midbody, anastomoses common. and 16 males in Tables 1-4. Lateral fields absent. Lip region low, bluntly rounded, not strongly set off. Description Styler flexible, delicate, elongate, repre- Female: Measurements in Tables 1-3. senting 19-22% of total body length. Co- Body club-like, slightly arcuate ventrally. nus representing 80-82% of total stylet Annules continuous, 1.0-1.6 wide (1.3 -+ length. Conus midpoint diameter 0.8-1.0 390 Journal of Nematology, Volume 27, No. 3, September 1995 TABLE 1. Measurements of 14 small paratype ing on host diet, containing amorphous in- (<500 p.m body length), non-gravid female Noctui- gesta, crystalline inclusions, and bacteria. donema dibolia n. sp. from Tift County, Georgia. Intestine ending in a blind, rounded sac Character ~ Mean SD Range extending posterior to vulva. Esophageal glands 45.3-65.7 long (59.7 +- 6.1) in small Measurements (p,m) non-gravid females, 43.8-77.4 long (66.7 Body length 455 37.2 396-495 Maximum body width 54 7.3 44-67 -+ 8.8) in large non-gravid females, and Body width at nerve ring 36 3.1 32-41 62.8-81.8 (72.8 +- 6.8) in large gravid fe- Body width at vulva 41 5.9 34-54 males. Body width at anterior 36 3.1 32-41 Ovary outstretched, .rarely reflexed, fre- end of intestine Anterior end to base 120 9.8 105-140 quently extending anterior to metacorpus of bulb in large specimens. Rachis present in large Metacorpus length 27 2.0 23-31 specimens. Oocytes progressively larger in Metacorpus width 23 1.8 20-26 posterior ovary, usually not more than one Excretory pore to 18 2.9 15-23 anterior end Stylet total length 99 6.1 83-108 TABLE 2. Measurements of 13 large paratype Stylet conus length 81 5.3 69-89 (>500 ~m body length), non-gravid female Noctui- Stylet shaftqength 18 3.0 15-23 donema dibolia n. sp. from Tiff County, Georgia. Head width 9 0.8 7-10 Head length 4 0.5 3-4 Character a Mean SD Range Ovary length 200 37.4 149-262 Vulva to end of tail 53 7.4 42-70 Measurements (~m) Vulva to anterior end 402 33.4 346-433 Body length 526 25.7 501-568 Vagina depth 24 4.1 18-31 Maximum body width 57 6.6 44---67 Anterior end to 129 25.4 85-187 Body width at nerve ring 36 4.6 28--44 anterior ovary Body width at vulva 44 6.7 32-54 Body width at anterior 36 5.3 26~4 Ratios and Percentages end of intestine a 8.5 0.7 7-10 Anterior end to bulb base 125 13.6 96-143 b 3.8 0.4 3-5 Metacorpus length 28 2.8 20-31 c 8.6 1.0 7-11 Metacorpus width 24 1.9 20-26 c' 1.3 0.2 1-2 Excretory pore to 19 2.5 15-23 V 88.3 1.3 86-91 anterior end M 82.0 2.6 76-86 Stylet total length 100 6.8 92-114 G 59.7 6.8 48-70 Stylet conus length 81 4.6 73-88 Ovary, % of body length 43.7 5.9 36-53 Head width 9 0.9 7-10 Stylet, % of body length 21.8 2.3 17-26 Head length 4 1.3 3-7 a a = body length/greatest body width; b = body length/ Ovary length 214 54.3 117-306 distance from anterior end to junction of esophagus and in- Vulva to end of tail 62 8.7 47-79 testine; c = body length/tail length; c' = tail length/body Vulva to anterior end 467 23.8 435-505 width at vulva; V = distance of vulva from anterior end x Vagina depth 27 5.4 15-34 100/body length; M = conus length x 100/styletlength; G = Anterior end to 136 28.6 67-175 distance from vulva to anterior end of ovary x 100/body anterior ovary length. Ratios and Percentages a 9.3 1.0 8-11 (1.0 -+ 0.1). Shaft diameter 1.0-1.6 (1.4 + b 4.2 0.4 4-5 0.3). Styler knobs rounded with concave c 8.7 1.1 7-11 anterior surfaces, 4.0-5.0 (4.6 + 0.4) wide, c' 1.5 0.3 1-2 V 88.7 1.8 86-92 6.0-20.0 (12.9 ± 4.9) from guide ring. M 81.1 4.7 73-89 Procorpus strongly reflexed at level of G 62.6 5.6 54-75 metacorpus when stylet is retracted.