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71.
72.
Heterostemma Wight & Arn. (Asclepiadaceae) and a new species from India. Heterostemma vasudemni Swarupanandan & Mangaly, a new species belonging to Asclepiadaceae is described and illustrated. The discoid-urceoloate corolla and the staminal coronal scales with a ventral appendage show this species to be intermediate between the two genera Heterostemma and Oianthus. Basically, the concepts of the two genera differ only in a pair of characters which, in the light of the new species seem not to be particularly diagnostic. On this basis it is proposed to merge the two genera together, by reducing Oianthus as a section under Heterostemma. Consequently, three new combinations are proposed. Examination of recent collections extends the distribution of what was 0. decanense , earlier considered to be endemic to Maharashtra, further south to Kerala.  相似文献   
73.
Coral successions in Upper Tortonian reefs in SE Spain   总被引:1,自引:0,他引:1  
Martin, Jose M., Braga, Juan C. & Rivas, Pascual 1989 07 15: Coral successions in Upper Tortonian reefs in SE Spain. Lethaia , Vol. 22, pp. 271–286. oslo. ISSN 0024–1164,
During the Upper Tortonian (Upper Miocene), the Almanzora river corridor, a small Neogene basin in SE Spain, harboured coral reefs growing in three different environments: in fan deltas, beyond the influence of coarse terrigenous sedimentation; in the abandoned lobes of a delta complex; and on coastal margins. All of these reefs are composed of several successive beds, each of which may be made up mainly of Porites embedded in silt or of an initial Porites level followed by a silt-free Tarbellastraea level on top. Porites may be associated with corallines. This structure is interpreted as being the result of an ecological succession repeated over and over again. A pioneer association consisting mainly of Porites . by colonizing the substrate and continuing to grow through relatively adverse silt-deposition conditions, prepares the ground for Tarbellastraea to take over. A return to the previous conditions halts the growth of the Tarbellastraea colonies and the Porites association once more establishes itself in the silt, or else the renewed rate of deposition is sufficiently heavy to suffocate the whole bioconstruction.* Ecological succession. coral reefs, Tortonian, southeast Spain .  相似文献   
74.
A new liquid medium, with fetal calf serum as the sole undefined component, was devised for the cultivation of Trypanosoma cruzi. The need for the serum is ascribed to its mitogenic proteins, which stimulate division of, and the uptake of [3H]thymidine by the parasites. In the new medium, T. cruzi has a cycle culminating in the appearance of up to 90% metacyclic forms in the stationary phase. This cycle is repeated on each serial transfer.  相似文献   
75.
SYNOPSIS. A new species of coccidium, Eimeria macusaniensis n. sp., is described from the alpaca Lama pacos in Macusani, Peru. The oocysts are ovoid to piriform, 81–107 by 61–80 μ (mean 93.6 by 67.4 μ) with a micropylar cap and elongate ovoid sporocysts 33–40 by 16–20 μ (mean 36.3 by 18.3 μ).  相似文献   
76.
The Mexican pseudothelphusid crabs are classified in one subfamily, three tribes, and 13 genera. Up to now, 56 species have been recognized, distributed in a strictly Neotropical pattern, with some of them reaching the state of Sonora on the western slope of Mexico. The tribe Pseudothelphusini is the most diverse, with five genera and 35 species, all of them endemic to Mexico: the two most species‐rich genera are Pseudothelphusa, with 23 species, and Tehuana, with eight species; Epithelphusa includes two species, whereas Disparithelphusa and Smalleyus are monotypic. The Pseudothelphusini lack an updated systematic revision, which could serve as a framework to analyse the monophyletic origin of the group, to clarify the relationships among genera and species, as well as to resolve the taxonomic status of various species complexes. In the present study, an exhaustive morphological revision was conducted using somatic and sexual characters. A phylogenetic analysis was performed using 77 characters and 183 character states, taken from 41 species. Ten trees of the same length were obtained using PAUP 4.0 through a heuristic search. The results show that the tribe as it is actually known constitutes a paraphyletic group, in which the species of Epithelphusa and Pseudothelphusa puntarenas are excluded from the internal group. According to the obtained results, the tribe Pseudothelphusini s.s. includes five genera: Smalleyus, Pseudothelphusa, Tehuana, and two new ones to accommodate Pseudothelphusa galloi and Pseudothelphusa sulcifrons, respectively. This new arrangement considers the provisional suppression of the genus Disparithelphusa, which remained as another species of Pseudothelphusa throughout the cladistic analysis. The phylogenetic results show a strong congruence with the distribution of the species, in several cases grouping species that form morphological clines along a geographical gradient. The previously proposed southern origin of the tribe Pseudothelphusini gains support with the results obtained. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 160 , 457–481  相似文献   
77.
SYNOPSIS. Starvation of Isotricha prostoma for 72–96 hours decreased the cellular amylopectin granules and facilitated the microscopic search for bacterial feeding. I. prostoma selected and ingested only certain rods from among many types of rumen bacteria. In order to isolate the bacteria important as a food source for Isotricha , the starved protozoa were allowed to feed on mixed rumen bacteria, washed, and the crushed protozoan contents quickly cultured for bacteria. Several strains of bacteria were isolated in pure culture. Three of the rod strains isolated were rapidly ingested by I. prostoma when fed to the ciliate. In a monobacterial culture I. prostoma divided once before succumbing.  相似文献   
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The Microbiotheriid Dromiciops gliroides , also known as 'Monito del Monte', is considered to be a threatened species and the only living representative of this group of South American marsupials. During the last few years, several blood samples from specimens of 'Monito del Monte' captured at Chiloé island in Chile have been investigated for blood parasites. Inspection of blood smears detected a Hepatozoon species infecting red blood cells. The sequences of DNA fragments corresponding to small subunit ribosomal RNA gene revealed two parasitic lineages belonging to Hepatozoon genus. These parasite lineages showed a basal position with respect to Hepatozoon species infecting rodents, reptiles, and amphibians but are phylogenetically distinct from Hepatozoon species infecting the order Carnivora. In addition, the Hepatozoon lineages infecting D. gliroides are also different from those infecting other micro-mammals living in sympatry, as well as from some that have been described to infect an Australian species of bandicoot. The potential vector of this parasite appears to be the host-specific tick Ixodes neuquenensis because the sequencing of a long amplicon determined the presence of one of the two lineages found in the marsupial.  © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 98 , 568–576.  相似文献   
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