Punctodera
Punctodera Mulvey & Stone, 1976 (ref. ID; 5922 original paper)
Family Heteroderidae (ref. ID; 5956, 7261)
ref. ID; 5922
Diagnosis
Mature female and cyst: Without posterior protuberance, spherical, ovoid, or pear-shaped. Cuticle with lacelike pattern of ridges and subsurface pattern of puctations. Vulval slit very short, underbridge absent. Bullae present or absent. Perineal tubercles absent. Circumfenestrate fenestra surrounding vulva and circumfenestrate fenestra of similar size surrounding anus. Anus offset toward ventral margin of anal fenestra. (ref. ID; 5922)
Second-stage juveniles: Stylet less than 30 µm. Esophageal glands fill body cavity. Phasmids without lenslike structure in muscle layer. (ref. ID; 5922)
Male: To 1.5 mm long. Labial disc present but with low profile. Tail present, less than half body width. (ref. ID; 5922)
Etymology
The name Punctodera is derived from the specific epithet of the type species and the Greek deros (skin) as modified to the Latin feminine by Schmidt in Heterodera. (ref. ID; 5922)
Type species
Punctodera punctata (Thorne, 1928) n. comb. (ref. ID; 5922)
- Punctodera chalcoensis Stone, Sosa-Moss, & Mulvey, 1976 (ref. ID; 7261)
- Punctodera matadorensis Mulvey & Stone, 1976 (ref. ID; 5922 original paper)
- Punctodera punctata (Thorne, 1928) n. comb. (ref. ID; 5922)
Syn; Heterodera (Globodera) punctata Thorne, 1928 (Skarbilovich, 1959) (ref. ID; 5922)
Punctodera chalcoensis Stone, Sosa-Moss, & Mulvey, 1976 (ref. ID; 7261)
Descriptions
Male: Male has a single cylindrical telogonic testis that extends from the cloaca at the posterior terminus to the midbody. The gonad wall is a single layer of epithelial cells enclosed by a basal lamina. (ref. ID; 7261)
Sperm: The epithelial lining of the male reproductive tract of P. chalcoensis is uniformly thin anteriorly. The middle region varies in thickness and the epithelial cells enclose electron-lucent vesicles; these vesicles enclose spherical secretory granules. Posteriorly, near the ejaculatory canal, the lining is thin dorsally and laterally but a few enlarged electron dense epithelial cells from a pronounced protrusion ventrally. In this species bundles of intestinal fasciculi are frequently associated with the male reproductive tract.
The sperm of P. chalcoensis are very small (about 2-5 µm in diameter), irregularly shaped because of the distribution of pseudopodia, and closely packed in the vas deferens with clusters of interdigitated filopodia compacted between cells. Filopodia are unevenly dispersed and few in number (lower than 10). In mature sperm, fibrous bodies are absent, mitochondria are abundant, and organelles are not polarized in distribution. Chromatin is highly condensed in one or more interconnected clumps near the center of the cell. The internal surface of the plasma membrane of P. chalcoensis sperm is lined by a single layer of cortical microtubules.
In inseminated females of P. chalcoensis, sperm are tightly packed in an enlarged spermatheca. These post-inseminated sperm apparently do not develop pseudopodia for attachment to the spermatheca wall. After insemination, sperm mitochondria as well as cortical and cytoplasmic microtubules remain abundant and the compact chromatin persists. (ref. ID; 7261)
Examined material
P. chalcoensis were isolated from cysts supplied by M. Mundo-Ocampo from a field population of corn (Zea mays L.) from Michoacan Mexico. (ref. ID; 7261)
Punctodera matadorensis Mulvey & Stone, 1976 (ref. ID; 5922 original paper)
Diagnosis
Punctodera matadorensis n. sp. differs from P. punctata (Thorne) in the shape of the cyst, which is ovoid to spherical for the former and pear-shaped for the latter. Four type cysts of P. punctata (USDA Collection, slide No. 3) have a mean L/W ratio of 1.4; the former has several well-developed bullae in the terminal area of the cyst that are absent in P. punctata. Examination of the terminal areas of cysts from Thorne's collection (USDA Collection, slide No.3a) revealed no bullae. Also, second stage juveniles described by Thorne (1928) for P. punctata are mush shorter in body length than those of P. matadorensis: 350-470 µm compared with 500-570 µm. (ref. ID; 5922)
Descriptions
Female: Body white, basically ovoid in shape, sometimes nearly spherical, with heavy subcrystalline layer. Neck relatively long. Cephalids not observed. Stylet fairly robust dorsally curved with basal knob sloping back anteriorly. Median esophageal bulb large with well-developed valve. Excretory pore at base of neck. Hemizonid and hemizonion not observed. Vulval slit length about 4 µm, set in a circular, translucent area of cuticle, the vulval fenestra; fenestral length 20 µm and width 20 µm. Anus a lateral slit, smaller than vulval slit, set in a circular translucent area of cuticle, the anal fenestra, offset to the ventral side. Fenestra in the female is obscured by the extension of the cuticle and, therefore, is not visible to scanning electron microscopy. Vaginal core distinct. Perineal tubercles and vulval bodies absent. Vulval and anal fenestra of about equal size. Cuticle with zigzag pattern of ridges and distinct subcuticular punctations. Mature female containing as many as 200 eggs. (ref. ID; 5922)
Cyst: Cyst light brown in colour, basically ovoid or spherical with small protruding neck. Several heavy bullae located between vulval and anal fenestra in all mature cysts. Both vulval and anal areas marked by circular fenestra, the vulval fenestra deteriorating rapidly to form a round aperture with a distinct circumfenestral area, which is absent for the anal aperture. (ref. ID; 5922)
Second-stage juvenile: Head distinctly set-off from rest of body, with four annules, oral disc elongate. Stylet massive with prominent forward-directed knobs. Anterior cephalids two annules behind head constriction, posterior cephalids at about the seventh annule. Hemizonid just anterior to level of excretory pore, which is located six or seven annules posterior to median esophageal bulb. Esophageal glands extending to nearly half body length. Tail tapering to rounded terminus, phasmids small but distinct, located in anterior half of tail. Lateral field with four incisures, reducing to three anteriorly and posteriorly, areolated. (ref. ID; 5922)
Male: Not found. (ref. ID; 5922)
Examined materials
Holotype: Collected from the roots of permanent grass, Matador Ranch, Matador, Saskatchewan, on June 12, 1971. Type slide No.224 deposited in the Canadian National Collection (CNC) of Nematodes, No.6435, Ottawa, Canada. (ref. ID; 5922)
Paratypes: Females, cysts, juveniles, eggs and terminal areas of mature females and cysts in the CNC of Nematodes, Ottwa, Canada; the United States Department of Agriculture (USDA) Nematode Collection, Beltsville, Maryland, and the Nematology Department, Rothamsted Experimental Station, England. (ref. ID; 5922)
Measurements
Female: Length(L) (excluding neck)=483(430-560) µm, width(W)=403(320-530) µm, L/W ratio=1.21(1.0-1.4), neck length 115-140 µm, stylet length 22(21-23) µm, dorsal esophageal gland opening from base of stylet about 5 µm (n=12). (ref. ID; 5922)
Female (Holotype): Length (excluding neck)=440 µm, width=400 µm, L/W ratio=1.1, neck length 140 µm. (ref. ID; 5922)
Second-stage juveniles:
- Fixed in 5% formol and mounted in lactophenol: Length=526(500-570) µm, width=19-20 µm; stylet length 24.6(24-25) µm, tail length 61.7(58-65) µm, hyaline terminal area length 39.1(35-42) µm, anterior of head to base of esophageal gland 222(200-250) µm (n=20). (ref. ID; 5922)
- Water mounts: Length=540(510-580) µm, width=21.2(20-22) µm, stylet length 24(23-25) µm, dorsal esophageal gland duct opening from base of stylet 5.5(5-6) µm, stylet knob width 5-6 µm, tail length 62(60-65) µm, hyaline terminal area length 36.5(35-40) µm (n=20). (ref. ID; 5922)
Embryonated eggs: Length=105-128 µm, width=43-50 µm (n=20). (ref. ID; 5922)