Males, second generation:. Second-generation male similar to that of the first generation except smaller, thinner, and distance from head to reflexion of testis much longer. Collapsed testis, found in first generation, very rare in second generation. Spicules and gubernaculum shorter and thinner than those of first generation male. Spicule with head/blade angle 151 degrees (143-160) (N=10). Gubernaculum almost as long as spicules, gubernaculum length divided by spicule length (G/S) 0.95 (0.92-1.0) (in other species G/S 0.52-0.75). Mucron on tail terminus very rare.
Females, first generation:(FIG.2) Body cuticle smooth or with faint annules. Lateral fields and phasmids not observed. Head rounded, continuous with body; perioral disc present; labial papillae 6, obscure, not seen in side view (seen clearly in side view of other species), 4 cephalic papillae. Lips indistinct. Amphids not observed. Stoma shallow, posterior part of stoma subtriangular. In lateral view, cheilorhabdions prominent, well sclerotized; another smaller sclerotization posterior to cheilorhabdions, presumably the prorhabdions. Esophagus with procorpus cylindrical, muscular; metacorpus slightly swollen; isthmus indistinct; basal bulb slightly enlarged. Nerve ring surrounds isthmus, usually obscure. Pronounced esophago-intestinal valve present. Excretory pore well anterior; distance from anterior end to excretory pore usually shorter than body width at excretory pore. Excretory cell very large. Gonads amphidelphic, reflexed, often containing many eggs. Vulva, a transverse slit, protruding on females with juveniles in body but not protruding on young females; double-flapped epiptygma present. Vagina sclerotized, short, about one-fourth body width, perpendicular to body in mature females, but directed posteriorly in young females. Body width greater anterior to vulva than posterior to vulva. Tail shape variable, ventral postanal swelling present or absent, tail usually shorter than anal body width. About 25% of population with tail longer than anal body width.
Females, giant form of first generation: In addition to the normal females of the first generation, a giant form of the female occurs along with regular first-generation females. The giant form is characterized by a twisted body and is two to three times longer than normal females of the first generation (10,313 - 13,000 micrometers compared to 3,531 - 6,250 micrometers). Other structures are as described for normal females.
Females, second generation: Similar to first generation female but smaller, and median bulb of esophagus slightly more enlarged. Ovaries containing at most three rows of eggs laterally. Tail, which tapers to a point, longer than anal body width; ventral postanal swelling present.
Infective juveniles(IJ): Body thin, elongate. Sheath (second-stage cuticle) present but sometimes lost. Labial region continuous. Oral aperture narrow Under electron microscope, labial papillae not seen; 4 cephalic papillae prominent (6 labial and 4 cephalic papillae prominent in S. carpocapsae); amphids present. Distance from anterior end to excretory pore extremely short, averaging 18 m vs. 38-83 m in other species. D% (distance from anterior end to excretory pore divided by esophagus length) and E% (distance from anterior end to excretory pore divided by tail length) 12 and 23, respectively. Esophagus with thin anterior part, basal bulb more or less elongate with visible valve. Lateral field with 7 incisures forming 6 bands, sometimes 8 incisures (7 bands) were observed. Tail attenuate, tapering gradually.
Character1 | Infective juvenile (50) | 1st gen female (40) | 1st gen male (10) |
---|---|---|---|
Body length | 885 SD 44 (741-988) | 8049 SD 860 (3531-13000) | 1593 SD 231 (1283-1988) |
Width | 34 SD 2.7 (28-42) | 218 SD 16 (159-289) | 111 SD 20 (77-144) |
Stoma length | - | 11 SD 1.6 (6-17) | 4.7 SD 0.8 (4-6) |
Stoma width | - | 13 SD 2.2 (8-20) | 6.9 SD 2 (3-9) |
EP | 18 SD 1.7 (14-22) | 41 SD 8 (23-59) | 31 SD 5 (19-34) |
NR | 107 SD 4 (100-119) | 216 SD 25 (153-295) | 123 SD 15 (108-158) |
ES | 144 SD 7 (130-159) | 287 SD 30 (181-356) | 165 SD 29 (125-231) |
Testis flexure | - | - | 360 SD 90 (279-512) |
Tail | 80 SD 5 (64-97) | 61 SD 9.5 (47-78) | 25 SD 6 (19-39) |
ABW | - | 70 SD 12 (50-100) | 41 SD 4 (39-50) |
Mucron length | - | - | 4 SD 0.8 (3-5) |
Spicule length (SP) | - | - | 59 SD 4 (52-64) |
Spicule width | - | - | 12 SD 1.7 (9-14) |
Gubern.length (GU) | - | - | 52 SD 4 (44-59) |
Gubern. width | - | - | 8 SD 1 (6-9) |
Vulva% | - | 50 SD 3 (42-56) | - |
a | 26 SD 2 (22-29) | - | - |
b | 6 SD 0.3 (5-7) | - | - |
c | 11 SD 0.8 (9-14) | - | - |
D% | 12 SD 1 (10-15) | 15 SD 3 (8-20) | 19 SD 4 (13-26) |
E% | 23 SD 2 (18-30) | - | |
SW= SP/ABW | - | - | 1.43 SD 0.14 (1.18-1.64) |
GS=GU/SP | - | - | 0.89 SD 0.04 (0.81-0.93) |
This document was constructed and is maintained by KHUONG
B. NGUYEN
Entomology & Nematology Department
University of Florida