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91.
Thecavermiculatus andinus n.sp. is described and illustrated from Oxalis tuberosa originally collected in the vicinity of Lake Titicaca high in the Andes mountains of southern Peru. This new species differs markedly front the other two species in the genus, especially in having a much greater female vulval-anal distance and annules with lined punctation on most of the female body with a lacelike pattern restricted to the posterior portion, particularly at the vulva and anus which do not protrude. Females are essentially spherical with protruding neck, white to yellowish in color, and can easily be mistaken for potato cyst nematodes. Among the dozen or more known weed and crop host plants are potato and eggplant. In order to accommodate this new species, the genus Thecavermieulatus is emended. A key to the species of this genus is presented. 相似文献
92.
Meloidogyne enterolobii n. sp. is described and illustrated from roots of pacara earpod tree, Enterolobium contortisiliquum (Vell.) Morong, on Hainan Island in China. The perineal pattern of the female is usually oval shaped, the striae are fine to coarse, the dorsal arch is moderately high to high and usually rounded, and the phasmids are large. The stylet knobs in females are divided longitudinally by a groove so that each knob appears as two. The mean distance of the excretory pore to the anterior end in the female is 62.9 μm. Males have a large, rounded labial disc that fuses with the medial lips to form a dorso-ventrally elongate head cap. The labial disc is slightly elevated, and the medial lips are crescent shaped. The second-stage juvenile mean body length is 436.6 μm. The lateral lips are large and triangular in face view. The tail is 56.4 μm long and narrow with a broad, bluntly rounded tip. M. enterolobii n. sp reproduces well on E. contortisiliquum and causes severe damage. Other good hosts include cotton, resistant tobacco ''NC 95,'' pepper, watermelon, and tomato. 相似文献
93.
H. C. Hechler 《Journal of nematology》1971,3(3):246-250
Panagrellus ceylonensis n. sp. is described from rubber latex in Ceylon. Its long, slender spicules are curved ventrally with a dorsal deflection at two-thirds of their length. The manubrium is thick and hooked, and the shaft is not widened at the shoulder. The terminal bifurcations are wide, with the dorsal one considerably longer and thicker than the ventral. The main ventral element is continuous with the terminal sheath with the ventral bifurcation arising within it. 相似文献
94.
95.
A comparative study of the epidermis of the common carp and the three Indian major carp 总被引:5,自引:0,他引:5
A comparative study has been made of the mucogenic epidermis of the common carp, Cyprinus carpio var. communis, and the three Indian major carps, Catla catla, Labeo rohita and Cirrhina mrigala: on the basis of epidermis structural organization, these species are easily differentiated. The epithelial cells in the superficial layer, as in most fishes, show secretory activity, evidenced by positive histochemical reactions, which is high in C. carpio var. communis, moderate in C. catla and low in L. rohita and C. mrigala. The epithelial cells in the underlying two or three layers also give positive reactions, though their intensity is relatively weak. The mucous cells in C. carpio var. communis are distributed in large numbers arranged in several superimposed layers in the outer regions of the epidermis, whereas in C. catla they are fewer in number and are widely separated in the surface layers as well as in the deeper layers of the epidermis; in both species the mucous cells appear rounded, large, and open on the surface by wide pores. In contrast, in L. rohita and C. mrigala the mucous cells are smaller, restricted mainly to the superficial layer, close together in a single row, and open on the surface by narrow pores. The overall density of mucous cells in L. rohita and C. mrigala, as in C. catla, is much lower than in C. carpio var. communis. In the epidermis of C. carpio var. communis there are a large number of mucous cells, and the few club cells are restricted to the deeper layers. In contrast, in the epidermis of the three Indian major carp the overall density of the mucous cells is much lower and the club cells are very numerous. It is suggested that the high density of club cells compensates an overall low density of mucous cells as an adaptation for an effective defence mechanism. Increased mucus production in the epidermis of C. carpio var. communis, as evidenced by a large number of mucous cells in outer regions and high secretory activity of superficial layer epithelial cells, is associated with increased precipitation of mud held in suspension, needed as an adaptation to the species’peculiar bottom-scooping habits. The varied density of the taste buds in the epidermis of the four carp is associated with their feeding habits. 相似文献
96.
Stylet ultrastructure of five Xiphinema, four Longidorus, and three Californidorus species was compared by scanning electron microscopy. Morphological differences were seen in the odontophores and odontostyle bases between the genera and some of the species. All Xiphinema studied had well-developed odontophore flanges; the Longidorus species lacked flanges, except for weakly developed ones in L. diadecturus; and none of the Californidorus had flanges. Three sinuses were present in the odontophores of all species. The sinuses varied in length depending upon species. In Xiphinema and Californidorus the odontostyle bases had distinct overlapping collars, but in Longidorus the collars were absent except for L. diadecturus. The odontostyle-odontophore junction from a lateral view appeared as a slanted transverse line in all the species, but in a dorsal view of Xiphinema and Californidorus it was V-shaped. Dorsal longitudinal seams of the odontostyle and odontophore were observed in all the species. The dorsally located odontostyle aperture was ca. 1 μm from the anterior end in all species, except in one Longidorus sp. it was ca. 4 μm from the end. 相似文献
97.
The CA1 pyramidal cells appear damaged in micrographs of guinea pig hippocampal slices incubated in normal physiological buffer at 36–37°C. This is remedied if slices are incubated in modified buffers for the first 45 min. Cell morphology is improved if this buffer is devoid of added Ca2+ and much improved if it contains N-methyl-D-aspartate (NMDA) receptor antagonists or 0 mM Ca2+ and 10 mM Mg2+. The cells then appear similar to CA1 pyramidal cells in situ. These findings support the notion that NMDA receptor activation and Ca2+, acting in the period immediately after slice preparation, permanently damage CA1 pyramidal cells in vitro. 相似文献
98.
Thomas F. Hourigan Frank G. Stanton Philip J. Motta Christopher D. Kelley Bruce Carlson 《Environmental Biology of Fishes》1989,24(2):105-116
Synopsis The foraging behavior and associated morphology of the feeding apparatus of three sympatric species of angelfishes, Holacanthus tricolor, Pomacanthus arcuatus and Pomacanthus paru were studied at St. Croix, U.S. Virgin Islands. All three had overlapping diets, consisting of algae and numerous species of sponges. The two Pomacanthus species also fed on gorgonians. The morphology of the dentition, jaws and gill rakers was similar in all three species. Male Holacanthus tricolor defended territories overlapping the foraging areas of two to four females. Within the male's territory, females defended smaller territories against other females of the same size, but tolerated smaller females. In contrast, both Pomacanthus spp. formed pairs which defended intraspecific feeding territories. 相似文献
99.
The brain organization of butterflyfishes 总被引:2,自引:0,他引:2
Roland Bauchot Jean-Marc Ridet Marie-Louise Bauchot 《Environmental Biology of Fishes》1989,25(1-3):205-219
Synopsis The encephalization indices of angelfishes (Pomacanthidae) and butterflyfishes (Chaetodontidae) are typical of advanced perciform
fishes: both families lie in the upper part of the polygon of teleost indices. The chaetodontids seem to be a little more
encephalized than pomacanthids. The general morphology of the brains in both families is very similar: small olfactory bulbs,
large optic tectum and a cerebellum which covers the brain structures in front of it like a cap. This morphology is shared
by another family of the coral reef biotope, the Acanthuridae. The histological architecture is also typical of advanced teleosts,
with a cortex-like pallium, a laminated nucleus geniculatus (= pretectalis superficialis), a complex valvula cerebelli and
a corpus glomerulosum with a clear neuropile centre. The quantitative analysis of the main subdivisions of the brain, either
from relative volumes or from indices, shows small olfactory bulbs (microsmy) but important telencephalic and diencephalic
centres, large tectal centres (vision) and large cerebellum (precise locomotion). Many of these peculiarities are shared by
other fishes inhabiting coral reefs. The differences between the two families seem to be primarily correlated with food habits:
the angelfishes, which are sponge-feeders and may have an overweight due to the ballast of the sponge-skeleton in their digestive
tract, and which do not need either such good vision or such precise locomotion to pick up their prey, could be a little less
encephalized than the butterflyfishes. 相似文献
100.
短尾猴(Macaca arctoides)和猕猴跟骨的功能形态研究 总被引:4,自引:0,他引:4
本文从形态描述和统计入手,对短尾猴(macaca arctoides)和猕猴的跟骨进行了比较研究。结果表明,所研究的跟骨变量无论数值大小还是几何图形结构都存在一定差异。特别是跟骨最大宽、跟长、后距骨连结面长、跟骨高度及相对跟长存在显著性差异水平。猕猴跟骨变量间的相关关系比短尾猴的表现得更为紧密。据其形态与功能的关系,我们认为:与猕猴相较,短尾猴更适应于地栖生活。这似乎与短尾猴具更大的体重有关。 相似文献