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61.
The two subspecies of the black spider monkey, Ateles paniscus paniscus and A. p. chamek, can be distinguished by their chromosome number, 2n = 32 in the former and 2n = 34 in the latter. This difference most probably is the result of a tandem fusion between chromosomes 4 and 13 of the original Ateles karyotype (2n = 34) to form a unique metacentric chromosome in A. p. paniscus. Further differences between the subspecies concern the presence of additional interstial or terminal C-bands in chromosomes 3, 5, and 12 of A. p. paniscus. A third difference is that chromosome 12 is metacentric in A. p. paniscus but is submetacentric in A. p. chamek. A. p. chamek shows dimorphisms caused by pericentric inversions in pairs 1, 5, 6, and 7 as well as in the Y chromosome. Since the dimorphisms in pairs 5 and 7 are only found in homozygous condition, they may indicate the existence of geographic variation within this subspecies. Differences in external characteristics possibly reflect these chromosomal difference. The necessity to lend A. p. paniscus full specific status should be considered, since karyologically this is the most distinct one of all forms of Ateles. In captive breeding A. p. paniscus should evidently be treated as a separate population, as hybridization with A. p. chamek may result in offspring with reduced fertility. The intra-subspecific karyological variation in A. p. chamek and its possible consequences for taxonomy and captive breeding require further investigation. 相似文献
62.
Abstract Chromosomal DNA molecules of Saccharomyces uvarum and Saccharomyces cerevisiae were separated using Orthogonal Field Alteration Gel Electrophoresis (OFAGE). Hybridization with specific probes of S. cerevisiae chromosomes allowed the identification of seven chromosomes of S. uvarum . The majority of the studied chromosomal DNA molecules show the same OFAGE mobility as the corresponding molecules of S. cerevisiae , with some minor differences.
Hybridizations with two distinct bands of S. uvarum were observed with each URA1 (marker of chromosome XI) and ARG80 (marker of chromosome XIII) probes, demonstrating the presence of at least two copies of these genes in the brewing yeast. 相似文献
Hybridizations with two distinct bands of S. uvarum were observed with each URA1 (marker of chromosome XI) and ARG80 (marker of chromosome XIII) probes, demonstrating the presence of at least two copies of these genes in the brewing yeast. 相似文献
63.
Synopsis Evidence is presented which suggests that the nonparasitic lamprey, Lampetra (Eudontomyzon) gracilis Kux, 1965, is conspecific with the parasitic lamprey Eudontomyzon danfordi Regan, 1911. The diagnostic characters of the holotype and of the non-type material of E. gracilis are features found in E. danfordi specimens in their second and final year of adult life, thereby making the former a junior synonym of the latter. 相似文献
64.
Elisabeth Stenzel Josef Heni Horst Rimpler Dieter Vogellehner 《Plant Systematics and Evolution》1988,159(3-4):257-271
Cluster analyses by different methods and a minimum spanning tree were used to study phenetic relationships in the genusChlerodendrum. 129 species were scored for 52 morphological characters corresponding to 119 character states. The phenetic results suggest a classification into 7 distinct groups, which may be grouped into two subgenera. This classification is supported by the iridoid distribution as well as by some phylogenetic considerations. 相似文献
65.
Sisinthy Shivaji N. Shyamala Rao L. Saisree Vipula Sheth G. S. N. Reddy Pushpa M. Bhargava 《Journal of biosciences》1988,13(4):409-414
Five cultures isolated from soil samples collected in Schirmacher oasis, Antarctica, have been identified as members of the
familyMicrococcaceae, with 3 belonging to the genusMicrococcus and two toPlanococcus. The 3Micrococcus isolates (37R, 45R and 49R) were red-pigmented and h a d ∼ 75 mol% G + C in their DNA; they were identified asMicrococcus roseus. The twoPlanococcus isolates (30Y and Lz3OR) were yellow and orange in colour, and had 43.5 and 40.9 mol % G + C in their DNA respectively; they
were identified asPlanococcus sp. 相似文献
66.
Meloidogyne mayaguensis n. sp. is described and illustrated from specimens obtained from galled roots of eggplant, Solanum melongena L., from Puerto Rico. The perineal pattern of females is round to ovoid with fine, widely spaced striae. It has occasional breaks of striation laterally and a circular tail tip area lacking striae. The stylet, 15.8 μm long, has reniform knobs that merge gradually with the stylet shaft. Males have a high, rectangular, smooth head region, not set off from the body contour. The labial disc is continuous with the medial lips which do not slope posteriorly. The styler, 22.9 μm long, has large rounded backward sloping knobs; the shaft is of uneven diameter. Mean body length of second-stage juveniles is 453.6 μm. The truncate head region is not annulated, and the rounded, slightly raised labial disc and the crescentic medial lips form dumbbell-shaped lip structures. The stylet, 11.6 μm long, has rounded, posteriorly sloping knobs. The slender tail, 54.4 μm long, gradually tapers to a bluntly pointed tip. Tomato, tobacco, pepper, and watermelon are good hosts; cotton and peanut are not hosts. M. mayaguensis n. sp. reproduces by mitotic parthenogenesis and has a somatic chromosome number of 2n = 44-45. The enzyme patterns are unique among Meloidogyne species. 相似文献
67.
Three new species of Etamphidelus are described from Orange Bay, Hoste Island, Chile. All three are distinguished from previously described species by their numerous longitudinal cuticular ridges. E. acucephalus n. sp. is further distinguished by its extremely narrowed anterior body region and posteriorly situated amphids. E. fueguensis n. sp. is distinguished from E. acucephalus by its anteriorly located amphideal fovea, fewer cuticular ridges, smaller V-an/tail ratio and presence of males. E. yamani n. sp. is more similar to E. fueguensis n. sp. differing from it by a wider head end, more posteriorly located excretory pore, longer V-an/tail ratio, more numerous cuticular ridges and smaller spermatozoa. E. puccinelliae (Lorenzen, 1966) Andrássy, 1977 is transferred to Paramphidelus puccinelliae (Lorenzen, 1966) n. comb. The generic diagnosis of Etamphidelus is amended, and a key to species is presented. 相似文献
68.
Tylenchulus graminis n. sp. and T. palustris n. sp. are described and illustrated from broomsedge (Andropogon virginicus L.) and pop ash (Fraxinus caroliniana Mill.), respectively. T. graminis resembles T. furcus in having a distinct anus, but T. graminis second-stage juveniles (J2) do not have a bifid tail. T. semipenetrans does not have a perceptible anus. The mature female of T. graminis has a mucronate pointed terminus while T. semipenetrans has a smooth and round terminus. T. graminis males have wider stylet knobs and basal bulb and a longer tail than T. semipenetrans males. T. graminis J2 have a longer posterior body portion (without large fat globules) than T. semipenetrans J2. T. palustris resembles T. semipenetrans in having an undetectable anus but differs by the short and conoid mature female postvulval section. The male of T. palustris has larger stylet knobs and basal bulb than those of T. semipenetrans and a bluntly rounded tail terminus, which is tapered in T. semipenetrans. T. palustris differs from T. furcus and T. graminis in having an undetectable anus, by the conoid postvulval section of mature females, by the shorter and rounded tail of males, and the shorter J2 posterior body section without large fat globules. T. graminis and T. palustris are parasites of indigenous flora of Florida. 相似文献
69.
Ocular structures have recently been discovered on the cephalon of an Ordovician agnostid trilobite, Oculagnostus frici (Holub, 1908). They are represented mainly by obvious palpebral lobes situated at the postero-lateral part of the genae. In addition, in one specimen there is a dome-shaped structure below the palpebral lobe. This may well be the remains of an eye, but details of its structure are indeterminate. In the other two cephala to hand there is a notch or cavity beneath the palpebral lobe, indicating that the visual surface may have been encompassed by a circum-ocular suture such that the lentiferous region normally dropped out during ecdysis. The origin of the ocular structures in Oculagnostus frici is briefly discussed. Oculagnostus n. gen. is described. 相似文献
70.
W. B. RUDMAN 《Zoological Journal of the Linnean Society》1988,93(2):133-185
The genus Ceratosoma (Nudibranchia: Chromodorididae) is reviewed and seven species, including two new species, are recognized. Species of the genus are known only from the Indo-West Pacific and it is suggested that the external body shape is the most useful character in distinguishing species. 相似文献