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1.
Clifford G.  Rice 《Journal of Zoology》1988,214(2):269-284
The reproductive biology of Nilgiri tahr ( Hemitragus hylocrius ) was studied in Eravikulam National Park, Kerala, India from August 1979 to September 1981.
The rutting season occurred during the monsoon (July and August) and the main birth season was January to mid-February. Gestation was estimated at 179 days.
Three females which lost their first young in 1981 conceived 18 to 21 days post-partum. One female conceived of her second young while the first was 15 days old. The remainder of the individually identified females gave birth to one young (n=40) or none (n=4).
Infant mortality was highest during the first two weeks after birth. Young born during the monsoon also had a high mortality rate (0.50/week).
Oestrus during the rut was discontinuous in 1980 and 1981. Periods of frequent oestrus corresponded with periods of low rainfall with a mean lag time of 4.9 days.
The ultimate factor determining the birth season in Nilgiri tahr appears to be weather. The main birth season is timed so as to minimize thermal stress.
Several proximal factors may be important in stimulating reproductive activity. These include photoperiod, temperature, the presence of males in mixed groups, and nutrition. The photoperiod response is unusual in that Nilgiri thar evidently respond to the abrupt decrease in apparent day length associated with the onset of the monsoon.
The inverse correlation of rainfall and oestrous activity may have been effected through the sudden decrease in thermal stress on the females or heavy rainfall (5.7 cm/day) masking pheromonal stimulation.
The pattern of lactation anoestrus observed in Nilgiri tahr approximates results obtained from some studies of domestic Caprini.
Nilgiri tahr females are presumably able to increase their lifetime reproduction by giving birth twice in one year. However, this strategy seemed counterproductive in 1981 as survival was low for second offspring.  相似文献   

2.
Efforts have been made to investigate the phylogeny of the family Bovidae; however, the relationships within this group still remain controversial. To further our understanding of the relationships, we sequenced the mitochondrial genome of the Himalayan goral, Naemorhedus goral, an IUCN Redlist near threatened conservation dependent species. Then we conducted molecular phylogenetic relationships of the Bovidae based on Bayesian and Maximum Likelihood methods. The results indicate that the basal divergence within the Bovidae is between the Bovinae and a strongly supported clade of the remaining Bovidae species. The two Neotragus species (the suni and pygmy antelope) clustered with the impala, Aepyceros melampus (Aepycerotinae), and together they formed the most basal of the non-Bovinae. All the genera of the Antilopinae clustered together except Neotragus, which suggested that the Antilopinae was a paraphyletic subfamily. The present study confirmed a close relationship between the genera Capricornis and Naemorhedus while supporting their designation as separate genera and suggested that the Capricornis-Naemorhedus-Ovibos clade (serows, gorals, and the muskox) should be placed in the Caprinae. Bison, Bos, and Tragelaphus (bison & cattle and kudus and nyalas) were paraphyletic. The very close relationship between Bison and Bos suggested that Bos and Bison should be integrated into a single Bos genus. Saiga and Pantholops (the Chiru or Tibetan Antelope), unique genera which have sometimes been lumped together, were placed in different groups: Saiga within the Antilopinae and Pantholops at the base of the Caprinae. Our results also supported a new taxonomy which places the three species of Hemitragus into three monospecific genera: the genus Hemitragus is restricted to the Himalayan tahr, and two new genera are created: Arabitragus for the Arabian tahr and Nilgiritragus for the Nilgiri tahr.  相似文献   

3.
The pollen morphology of 120 samples of the tribe Orobancheae, representing four genera and 40 species of Cistanche, Diphelypaea, Orobanche and Phelipanche native to Turkey, has been studied by light and scanning electron microscopy. Pollen of the tribe Orobancheae is typically isopolar, radially asymmetrical, oblate spheroidal or prolate and belongs to one of the following basic pollen types: inaperturate, tricolpate and syncolpate. Also, pollen heteromorphism is widespread among pest species of Orobanche and Phelipanche. Pollen characters display considerable variation among genera and species, but some characters are significant at the levels of genera and sections. The results of the SEM study show that there are various exine ornamentation types in these genera. The obtained results support the division of the traditionally circumscribed genus Orobanche sensu lato into two genera, Phelipanche and Orobanche. The pollen morphological features are discussed on the basis of molecular phylogeny of the taxa.  相似文献   

4.
A new genus and species, Cryptohelops menaticus gen. et sp. n., are described from the Palaeocene of Menat (France). The new genus belongs to the subtribe Helopina of the tribe Helopini (subfamily Tenebrioninae of Tenebrionidae) based on the coarse and dense punctation of the hypomera, shape of the prosternum and metepisterna, a similar appearance to the native genera Helops and Stenohelops and the structure of the epipleura. The new genus also resembles Raiboscelis and Entomogonus by having the protibiae excised along the base of the inner side. The new genus is the oldest representative of the tribe Helopini. Four species of Helops sensu lato previously described from the Oligocene (H. wetteravicus K. Heyden et L. Heyden, 1865) and Miocene (H. atticus Redtenbacher in Ungern, 1867; H. meissneri Heer, 1847 and H. molassicus Heer, 1883) lack important diagnostic characters and should be regarded as members of the tribe Helopini with uncertain generic attribution.  相似文献   

5.
Tang L  Li LZ  Růžička J 《ZooKeys》2011,(124):19-39
A new cicadellid tribe, Tungurahualini, is recognized to include Tungurahuala Kramer, and a related new genus, Ilyapagen. n., based on six new species. The tribe is included in subfamily Mileewinae, the concept of which is further expanded to include tribes Makilingiini Baker, and Tinteromini Godoy and Webb, taxa previously treated as separate subfamilies. Keys to tribes of Mileewinae (sensu lato) and genera of Tungurahualini are provided. A new species of Tungurahuala, Tungurahuala acuminatasp. n., is also described and keys to species of Tungurahuala and Ilyapa are provided. The new tribe is presently recorded only from cloud forests in the northern Andes Mountains of South America.  相似文献   

6.
Panicum L. is a cosmopolitan genus with approximately 450 species. Although the genus has been considerably reduced in species number with the segregation of many taxa to independent genera in the last two centuries, Panicum remains a heterogeneous assemblage, as has been demonstrated in recent years. The genus is remarkably uniform in its floral characters but exhibits considerable variation in anatomical, physiological, and cytological features. As a result, several classifications, and criteria of what the genus should really include, have been postulated in modern literature. The purpose of this research, based on molecular data of the chloroplast ndhF gene, is to test the monophyly of Panicum, to evaluate infrageneric classifications, and to propose a robust phylogenetic hypothesis. Based on the present results, previous morphological and molecular phylogenetic studies, and inferred diagnostic morphological characters, we restrict Panicum sensu stricto (s.s.) to the former subgenus Panicum and support recognition of Dichanthelium, Phanopyrum, and Steinchisma as distinct genera. We have transfered other species of Panicum to other genera of the Paniceae. Most of the necessary combinations have been made previously, so few nomenclatural changes have been required. The remaining species of Panicum sensu lato (s.l.) are included within Panicum incertae sedis representing isolated species or species grouped within monophyletic clades. Additionally, we explore the performance of the three codon position characters in producing the supported phylogeny.  相似文献   

7.
Twenty-nine free-ranging Himalayan tahr (Hemitragus jemlahicus) were darted in the Sagarmatha National Park (Nepal) using different combinations of xylazine and ketamine. Animals in Group 1 (n = 4) received a mean xylazine-ketamine dose of 2.77 +/- 0.99 mg/kg xylazine plus 3.32 +/- 0.19 mg/kg ketamine in males and 2.39 +/- 0.10 mg/kg xylazine plus 4.29 +/- 0.17 mg/kg ketamine in females. Animals in Group 2 (n = 25) received a mean xylazine-ketamine dose of 1.70 +/- 0.41 mg/kg xylazine plus 3.06 +/- 0.74 mg/kg ketamine in males and 1.82 +/- 0.29 mg/kg xylazine plus 3.29 +/- 0.52 mg/kg ketamine in females. No anesthetic-related mortality was recorded. Anesthesia was reversed by a standard dose of 11 mg/animal of atipamezole administered by intramuscular injection. Although all anesthetic dosages immobilized free-ranging tahr successfully, a quick and smooth recovery was obtained (11.1 +/- 5.6 min) only with the dosages of Group 2.  相似文献   

8.
亚洲蝮亚科蛇属间系统发生支序分析 (蛇亚目:蝰科)   总被引:1,自引:0,他引:1  
郭鹏  张服基 《生命科学研究》2000,4(3):262-266,280
在大量比较形态研究的基础上,选择了5个特征方面28个性状,以支序分析方法探讨了分布于亚洲蝮亚科蛇5属14种的系统发生关系,结果表明:该亚科蛇类可以划分为3个不同的类群,第一个类群包括尖吻蝮属、瘤鼻蝮属、红口腹属,它们具有较多的祖征,代表了该科中原始一类,基中红口蝮可能是最原始的一属;亚洲蝮属单独形成一个类群;第三个类群为原广义的烙铁头蛇属,包括竹叶青蛇属、原矛蝮属、烙铁头蛇属、黑绿烙铁头蛇属、莽山  相似文献   

9.
In order to investigate the taxonomic value of a number of characters in the elucidation of relationships within the collective genus Polygonum L., and segregate genera Atraphaxis L., Calligonum L., Pteropyrum Jaub. & Spach., Oxygonum Burch., Fagopyrum Mill., Harpagocarpus Hutch. & Dandy and Polygonella Michx., 83 species of the tribe Polygoneae emend. Jaretzky were studied. The following floral characters were examined: stamen number, insertion and external morphology; structure and morphology of the floral nectaries; vasculature and surface morphology of the tepals.
Problems in floral morphology in Polygonaceae are discussed, together with relationships within the Family. The tribal division proposed by Haraldson (1978) is supported, but a new and different delimitation of genera is proposed. The present data support a division of Polygonum L. sensu lato and its related taxa into two tribes: Polygoneae (containing Polygonum L. sensu stricto, Fallopia Adans., Oxygonum Burch., Pteropyrum Jaub. & Sparh., Atraphaxis L. and Calligonum L.), and Persicarieae (containing Fagopyrum Mill., Harpagocarpus Hutch. & Dandy, Persicaria Mill. and Koenigia L.). The genus Reynoutria Houtt. is included as a section of Fallopia Adans.; Bislorta Mill., Aconogonon Reichenb. and Tovara Adans. are included within Persicaria Mill.
A number of new combinations are proposed in Persicaria and Fallopia .  相似文献   

10.
Legume subfamily Caesalpinioideae accommodates approximately 2250 species in 171 genera which traditionally are placed in four tribes: Caesalpinieae, Cassieae, Cercideae and Detarieae. The monophyletic tribe Detarieae includes the Amherstieae subclade which contains about 55 genera. Our knowledge of the relationships among those genera is good in some cases but for many other genera phylogenetic relationships have been unclear. The non-monophyletic nature of at least two amherstioid genera, Cynometra and Hymenostegia has also complicated the picture. During the course of a multi-disciplinary study of Hymenostegia sensu lato, which includes phylogenetic analyses based on matK and trnL data, we have recovered the “Scorodophloeus clade”, an exclusively tropical African clade of four genera which includes the eponymous genus Scorodophloeus, two undescribed generic segregates of Hymenostegia sensu lato, and the previously unsampled rare monospecific genus Micklethwaitia from Mozambique. Zenkerella is suggested as a possible sister genus to the Scorodophloeus clade. A distribution map is presented of the seven species that belong to the Scorodophloeus clade.  相似文献   

11.
Species delimitation in Hymenochaete sensu lato was evaluated based on partial nucLSU rDNA sequences, isoenzyme analyses and morphological data. Analyses of LSU data revealed Hymenochaete sensu stricto and Pseudochaete as distinct monophyletic genera. Transfer of Hydnochaete olivacea into genus Pseudochaete and Dichochaete setosa into genus Hymenochaete (as H. resupinata) was supported by the results of molecular analyses. A new species Hymenochaete koeljalgii from Tanzania was described. The species of genus Hymenochaete sensu stricto were divided into four well-supported clades possessing no distinctive morphological characters.  相似文献   

12.
A comprehensive higher‐level phylogeny of diving beetles (Dytiscidae) based on larval characters is presented. Larval morphology and chaetotaxy of a broad range of genera and species was studied, covering all currently recognized subfamilies and tribes except for the small and geographically restricted Hydrodytinae, where the larva is unknown. The results suggest several significant conclusions with respect to the systematics of Dytiscidae including the following: monophyly of all currently recognized subfamilies, although Dytiscinae when considered in a broad context is rendered paraphyletic by Cybistrinae; currently recognized tribes are monophyletic except for Agabini, Hydroporini and Laccornellini; inter‐subfamily and inter‐tribe relationships generally show weak support, except for a few well supported clades; three distinct clades are recognized within Dytiscinae [Dytiscini sensu lato (i.e. including the genera Dytiscus Linnaeus and Hyderodes Hope), Hydaticini sensu lato, and Cybistrini]; and recognition of Pachydrini as a distinct tribe. Other less robust results include: Methlini sister to the rest of Hydroporinae; relative basal position of Laccornini, Hydrovatini and Laccornellini within Hydroporinae; close relationship of Agabinae and Copelatinae; Matinae nested deep within Dytiscidae, as sister to a large clade including Colymbetinae, Coptotominae, Lancetinae and Dytiscinae sensu lato; the sister‐group relationship of Agabetini and Laccophilini is confirmed. The results presented here are discussed and compared with previous phylogenetic hypotheses based on different datasets, and the evolution of some significant morphological features is discussed in light of the proposed phylogeny. All suprageneric taxa are diagnosed, including illustrations of all relevant synapomorphies, and a key to separate subfamilies and tribes is presented, both in traditional (paper) format and as an online Lucid interactive identification key.  相似文献   

13.
Recent molecular systematic investigations suggested that Ferula, an umbellifer genus of about 170 species, is polyphyletic, with its members placed in the apioid superclade and within tribe Scandiceae. We analyzed ITS sequence variation from 134 accessions of Apiaceae, including 83 accessions (74 species) of Ferula to ascertain the phylogenetic position of the genus within the family. Phylogenetic analyses of these data using maximum parsimony, Bayesian, and neighbor-joining methods support the monophyly of Ferula upon the addition of Dorema and Leutea (as Ferula sensu lato) and its placement in tribe Scandiceae. Ferula sensu is closely allied with other major lineages of Scandiceae, corresponding to subtribes Scandicinae, Daucinae, and Torilidinae. Therefore, we recognize the Ferula clade as subtribe Ferulinae. Another addition to tribe Scandiceae is a clade composed of genera Glaucosciadium and Mozaffariania. The three accessions of Ferula misplaced in the apioid superclade represent a species of Silaum.  相似文献   

14.
槭树科植物广义形态学性状分支分析   总被引:4,自引:0,他引:4  
通过45个广义的形态学性状对槭树科(Aceraceae)尤其是槭属(Acer L.)的主要类群做了分支分析,结果显示:1)槭属内由于各类群分布着较多的同塑性状状态,而难以为属下组间关系的解决提供更多有价值的信息;通过对具体的性状状态分布分析显示,对于象槭属这样在形态上分化较大的类群,由于多数分类性状在不同类群间经历了平行和逆转演化,因而在较低分类阶元水平很难选择合适的性状来通过分支分析构建其系统发育;2)鸡爪槭组(section Palmata)作为整个槭属的基部类群,虽然支持率较低,但与其它类群相比在槭属内维持了较多的原始性状;3)金钱槭属(Dipteronia Oliv.)的两个种作为单系得到了100%的靴带支持,且和槭属作为姐妹群也得到了较好的支持。  相似文献   

15.
The tribe Convallarieae (sensu Krause 1930) consists of 7 genera, i.e. Convallaria, Speirantha, Reineckia, Theropogon, Tupistra, Rohdea and Aspidistra, but now generally recognized as two tribes, Convallarieae (the former 4 genera) and Aspidistreae (the rest). Observed in this work were pollen morphology of 17 species and epidermal characters of leaves of 12 species. All the 7 genera are covered in observations. Pollen grains in Convallarieae (s. str.) are all monosulcate and boat-shaped (Plate 1: A-F). The exine is rather uniformly microperforate (Plate 1: A-F); only Theropogon is exceptional in this respect: it has rugulate exine (Plate 1: O, P). Tang and Zhang (1985) have pointed out the heterogeneity of Theropogon in this tribe. Pollen morphology in the tribe Aspidistreae is widely variable. The genera Tupistra and Rohdea were shown to have monosulcate and boat-shaped pollen grains. Their exine is perforate or reticulate (Plate 1: G-N). Pollen grains in the genus Aspidistra, however, are nonaperturate and spheroidal. The exine in the genus varies from crass-rugulate, variously gemmate to tuberculate-baculate (Plate 2; A-H). The pollen morphology of Aspidistra is therefore distinctly different from that of Tupistra and Rohdea, which supports the Nakai's (1936) establishment of the tribe Rohdeae for Tupistra and Rohdea. Therefore, Krause's Convallarieae is reasonably divided into at least three tribes, Convallarieae (Speirantha, Convallaria, Reineckia and Theropogon), Aspidistreae (Aspidistra) and Rohdeae (Rohdea and Tupistra). The pollen characters of all the 7 genera are shown in Table 1. The evolutionary trends of pollen morphology (aperture and exine) in the three tribes are discussed and our major view-points are shown in Fig. 1. Observations on epidermal characters of leaves show that in the Convallarieae (s. 1.) stomatal apparatuses are all anomocytic; cuticular layer on the upper epidermis is mainly striatethickened or rather uniformly thickened (Plate 2: J--P; Plate 3: A-C, F-N), whereas in the genus Convallaria the cuticular layer is squamosely thickened (Plate 2: I; Plate 3: D, E).The epidermal characters of leaves in the 7 genera are summarized in Table 2.  相似文献   

16.
Complete cytochrome b gene sequences allows, for the first time, establishing a nearly complete phylogeny among the Praomys group sensu lato. The genera Praomys, Mastomys and Stenocephalemys appear paraphyletic. Myomys is polyphyletic and this genus name probably needs to be restricted to its type species, M. verreauxii. The genera Zelotomys and Colomys appear as sister groups. Mastomys pernanus and Malacomys verschureni nest within the Praomys group, but their generic assignation must be further clarified. The genus Heimyscus appears closest to Praomys than to Hylomyscus. The different lineages probably result from an adaptive radiation at the end of the Miocene.  相似文献   

17.
In ungulates, rank order is determined by differences in weight, body size, weapon size and age. In the Caprini tribe (Bovidae: Caprinae), adult male Himalayan tahr are unique to show different coat colours, but no sexual dimorphism in weapons. A highly significant correlation between hair colour and rank order was found during the rut: males with a lighter coloured ruff dominated over darker ruffed ones, in both aggressive interactions and access to oestrus females. We studied colour-based dominance in relation to weight, age and testosterone levels, which establish the social rank in most ungulates. No differences in weight and testosterone concentrations were found between adult male colour classes, but males with paler ruffs were significantly younger than darker adult males. The distribution of physical traumas from fights confirmed that younger, lighter-coloured males had a higher rank than older, darker males, a pattern which is unusual amongst ungulates. Coat colour seems to work as a signal of rank in male-male aggressive interactions and it changes according to age, whereas the relevant physiological determinants deserve further research. Intrasexual male competition has not changed weapon size or shape in the Himalayan tahr, but ruff colours are apparently used to signal rank and dominance. Colour patterns of adult males may then be homologous to ritualised weapons, apparently being a unique feature of male tahr amongst mammals.  相似文献   

18.
19.
Himalayan thar or tahr (Hemitragus jemlahicus), Alpine chamois (Rupicapra rupicapra) and brushtail possums (Trichosurus vulpecula) are native to the Himalaya, Europe and Australia, respectively, but are now sympatric in parts of the central Southern Alps, New Zealand. All three species are managed as pests by the Department of Conservation. We analysed the diets of 246 thar, 78 chamois and 113 possums collected in the central Southern Alps during 1988–1996. The diets of thar and chamois strongly overlapped, but thar ate more grasses and less herbs and woody plants than chamois. The diet of possums differed from the diets of thar and chamois, containing a different suite of herbs and almost no grasses. The diets of thar, chamois and possums varied seasonally. Contrary to expectation, the diets of adult male and female thar were similar during the period when they are spatially segregated (October–May). Chamois sampled outside the thar range ate more species than those sampled inside the thar range, suggesting that the presence of thar modifies the diet of chamois. If managers wish to protect the dominant Chionochloa snow tussocks then thar should be controlled; chamois should be controlled to protect herbs such as Ranunculus spp.; and possums should be controlled if Podocarpus nivalis or Muehlenbeckia axillaris need to be protected. However, managers need to be aware of the potential for chamois to increase in abundance, at least in some sites, if thar are controlled to low abundance, and that this could lead to different impacts on plant populations.  相似文献   

20.
There is anecdotal evidence that increasing densities of Himalayan tahr (Hemitragus jemlahicus) are associated with declining densities of chamois (Rupicapra rupicapra) in the Southern Alps, New Zealand. To examine this phenomenon, densities of tahr and chamois were measured at 53 sites within their sympatric range in the eastern Southern Alps during 1978–1979. In sites where only one species was present, tahr density was significantly higher than chamois density (P=0.032), probably reflecting species differences in sociality. Chamois density was higher in catchments without tahr than in those with tahr (P=0.012). Similarly, tahr density was significantly higher at sites without chamois than at those with chamois (P=0.033). Sites with both species present (termed sympatric) were significantly larger than those with only chamois or tahr (P<0.001). Following the prohibition of aerial hunting of tahr in 1983, 16 of the 17 sites where tahr and chamois were sympatric during 1978–1979 were recounted during 1991–1996. There was a 6-fold increase in the mean density of tahr between the two counts (P=0.001), whereas chamois density had declined significantly (P=0.006). Chamois persisted at only three sites, two of which had the highest chamois densities in 1978–1979. This is evidence that increasing densities of tahr exclude chamois from all but the `best' habitats. We conclude that intensive aerial hunting of tahr during 1967–1983 reduced tahr densities such that chamois could co-exist with tahr. Received: 20 March 1997 / Accepted: 8 September 1997  相似文献   

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