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1.
Mesoplodon peruvianus , a new species of beaked whale, is described on the basis of ten specimens which have either stranded or been captured between 11°12'S and 15°19'S latitude along the coasts of the provinces of Lima and Ica, south central Peru. This is the thirteenth living species of Mesoplodon recognized in the world's oceans. The animals that were examined were uniformly gray above, shading to lighter gray below. This whale is the smallest species of Mesoplodon (maximum body length 3.72 m) and is characterized by its teeth, which are small (31 to 65 mm long), ovate in cross section, and positioned 2.5% to 8.4% of the mandibular length from the anterior extremity, and posterior to the mandibular symphysis.  相似文献   

2.
Mesoplodon perrini , a new species of beaked whale is described on the basis of five animals stranded on the coast of California (between 32°55'N, 117°15'W and 36°37'N, 121°55'W) from May 1975 to September 1997. Four of these animals were initially identified as Hector's beaked whales M. hectori based on cranial morphology (Mead 1981). A fifth specimen was initially identified as a neonate Cuvier's beaked whale Ziphius cavirostris based on external features. These specimens were first recognized as representatives of an undescribed species through phylogenetic analysis of mitochondrial (mt) DNA control region and cytochrome b sequence data. Although similar morphologically, the genetic data do not support a close evolutionary relationship between M. perrini and M. hectori . Instead, these data suggest a possible sister species relationship with the lesser beaked whale M. peruvianus . Sightings of two small beaked whales off California in the 1970s which were tentatively identified as M. hectori are also likely to be M. perrini . We suggest that M. hectori is confined to the Southern Hemisphere, while M. perrini is known to date only from the North Pacific.  相似文献   

3.
Mesoplodon traversii (Gray, 1874) is shown to be a senior synonym of the recently described beaked whale Mesoplodon hahamondi Reyes et al. , 1995 on the basis of a phylogenetic analysis of mitochondrial DNA control region sequences. The mandible and teeth of M. traversii , first reported in 1873 by Hector as Dolichodon layardii . are redescribed. The species can be distinguished by features of the calvaria; including the large jugal, broad rostrum, and small distance between premaxillary foramina. The male teeth, which are large and spade-shaped with a strong terminal denticle, are also diagnostic. M. traversii is known only from Pitt Island and White Island, New Zealand and Robinson Crusoe Island, Juan Fernandez Archipelago, Chile.  相似文献   

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Summary

The ocypodid genus Paratylodiplax was described in 1974 and contains four species, three of which are endemic to southern Africa where they form an important component of the estuarine benthic fauna. However, very little is known about the biology and ecology of the genus, with discrepancies existing between the commonly quoted distributions and actual records of the species. This comment outlines the current taxonomic status of the genus and attempts to resolve the discrepancies in the distributions of the southern African species Paratylodiplax blephariskios has been recorded from the Morrumbene estuary in Mozambique to the Mngazana estuary in the eastern Cape, while the distributions of P. algoensis and P. edwardsii are given as being from the Mngazana to the Eerste estuary and Langebaan Lagoon in the western Cape respectively.  相似文献   

8.
The vaquita, Phocoena sinus , is a porpoise in the family Phocoenidae that lives only in the Gulf of California. The external appearance of P. sinus was unknown until 13 fresh specimens were recently examined. The most obvious morphological feature distinguishing P. sinus from its two congeners is the proportionately higher dorsal fin. The most striking features of the pigmentation pattern are the large black eye patches and the black upper and lower lip patches. In both areas, the pigmentation contrasts sharply with the surrounding light gray coloration. The total lengths of the specimens ranged from 70.3 cm (a neonate) to 143.5 cm (an adult female).  相似文献   

9.
从广西北部地区作物根围采集土壤标样323个,分离纯化出腐霉菌株260个,共15种。其中7种为广西新记录,即棘腐霉Pythiumacanthicum,浮游腐霉P.aquatile,宽雄腐霉P.dissotocum,缺性腐霉P.elongatum,孤雌腐霉P.amasculinum,禾生腐霉P.graminicola,绚丽腐霉P.pulchrum。优势种为瓜果腐霉P.aphanidermatum,其余7种为刺腐霉P.spinosum,德里腐霉P.deliense,昆明腐霉P.kunmingense,南宁腐霉P.nanningense,刺器腐霉P.acanthophoron,终极腐霉P.ultimum,镰雄腐霉P.falciforme。同时对腐霉的地理分布情况进行了初步探讨,发现腐霉分布有着明显的地域性。  相似文献   

10.
虎斑夜鳽分布与亚群态势研究   总被引:3,自引:0,他引:3  
本世纪以来对虎斑夜鳽分布地点的新发现,表明该种从滨海到内陆漫布于中国长江以南广大地区,并向北渗透直逼东洋界北限秦岭-淮河一线;作者据此将各地的虎斑夜鳽初划为11个亚群,提出目前该种存有3个相对健康而稳定的亚群,即黄山-天目山亚群、南岭亚群和广西亚群,且每个亚群的分布范围均至少不会小于5000km2,其中以黄山-天目山亚群的记录由历史至现今相对最为长久而完整,进而提出今后在上述诸亚群范围之外还会有新的发现.文中指出,尽管近期对虎斑夜鳽分布状况有了新认识,目前仍可视该种的受胁等级为濒危.  相似文献   

11.
Sperm whales ( Physeter macrocephalus ) and beaked whales ( Mesoplodon spp. and Ziphius cavirostris ) are deep-diving cetaceans that frequent shelf-edge and Gulf Stream waters off the northeast U. S. coast. Sighting data collected during seven summer (1990, 1991, 1993, and 1995–1998) shipboard surveys were analyzed using a geographic information system to determine habitat use based on bathymetric and oceanographic features. Although sighting rates were lower for beaked whales, both taxa occupied similar habitats. Beaked whales were concentrated at the colder shelf edge, whereas sperm whales were associated with warmer off-shelf water. Mean sighting rates for both taxa were higher in canyon features, but only beaked whale sighting rates were significantly different between canyon and non-canyon habitat (Wilcoxon signed rank test P = 0.007). Within the shared habitat, the two taxa were separated at fine-scale based on oceanographic features.  相似文献   

12.
The freshwater rhodophyte Balbiania investiens (Lenormand) Sirodot was collected as an epiphyte of Batrachospermum in small streams in England, Ireland, and Germany. Unialgal cultures and field collections of Balbiania were analyzed in terms of their morphology, ultrastructure, and the DNA sequences of the genes coding for the large subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase ( rbc L) and 18S ribosomal RNA (rRNA), as well as the first internal transcribed spacer region (ITS1) of the rRNA genes. One of the major distinguishing features of this genus is the production of spermatangia on the tips of specialized, elongate cells. The spermatangia are cut off in a cluster together with similar nonspermatangial cells that are packed with starch granules. The only other rhodophyte genus with this feature is Rhododraparnaldia ; the two genera are differentiated from each other by the pattern of branching, substratum of attachment, and type of diploid phase. In the parsimony and distance trees inferred from the two gene sequences as well as in a combined parsimony tree, Balbiania and Rhododraparnaldia grouped together on a well-supported branch separate from other taxa of the Batrachospermales, Acrochaetiales, Nemaliales, and Palmariales. However, the two genera are positioned within a clade containing the last three orders. Based on these findings, it is clear that the genus Balbiania is a valid taxon and that it is phylogenetically associated with Rhododraparnaldia. A new order is proposed, the Balbianiales. The two specimens of Balbiania analyzed from England and Germany have identical sequences for all regions of DNA analyzed.  相似文献   

13.
中国原花蝽属新种及新纪录(半翅目:花蝽科)   总被引:1,自引:0,他引:1  
本文记载中国花蝽科原花蝽属Anthocoris Fallen新种6个,计为:黑角原花蝽A.atricarnis sp.n.(模式产地:云南),哀牢原花蝽A.ailaoanus sp.n.(模式产地:云南),杨氏原花蝽A.yangi sp.n.(模式产地:云南),刺突原花蝽A.armatus sp.n.(模式产地:云南),萧氏原花蝽A.hsiaoi sp.n.(模式产地:四川、陕西),秀原花蝽A.concinnus sp.n.(模式产地:西藏)。文章并记录此属的3个中国新记录种;并为已被占用的A.elongatus Zheng 1982命以新名:A.longiusculus nom.nov.  相似文献   

14.
袁锋  王敏 《昆虫分类学报》1994,16(2):115-119
本文描述采自陕西的环蛱蝶属1新种-周环蛱蝶Neptischouisp.nov.;将黄环蛱蝶伊洛亚种NeptisthemisilvsFuhstorfer提升为种,即伊洛环蛱蝶NeptisilvsFruhstorfer,认为黄环蛱蝶台湾亚种NeptisthemisnieriNomura应为伊洛环蛱蝶NeptisilvsFruhstorfer的1个亚种,描述了伊洛环蛱蝶的1新亚种-四川亚种Neptisi  相似文献   

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16.
黑长臂猿的分布、现状与保护   总被引:10,自引:0,他引:10  
黑长臂猿 (Hylobates concolor)是现生 1 1种长臂猿中其系统地位最低的灵长类。历史时期长臂猿曾广泛分布在我国南部的大部省区。自公元 4世纪以来 ,它们的分布发生了很大变化。分布区从北到南 ,从东到西急剧缩小 ,现黑长臂猿缩小到只在海南岛、云南南部和越南北部 ,已分化为 6个亚种。分布于我国的 5亚种中 ,海南亚种 (H . c. hainanus)现今仅20余只 ,是最濒危的一个亚种 ;.北部湾亚种 (H.c.nasutus) 50年代曾在广西西南部发现 ,60 -70年代已绝迹 ;指名亚种 (H.c.concolor)主要分布于越南北部、滇南和滇中哀牢山。滇南约有100余只 ,滇中哀牢山可能有40 - 60群 ,180 - 240只 ;景东亚种 (H . c. jingdongensis)为滇中无量山的特有亚种 ,现有100 - 116群 ,430 - 500只 ;滇西亚种 (H . c. furvogaster) ,只分布在滇西南的沧源、镇康、云县和耿马等地 ,约有 2 6-42群 ,100 - 150只。现今 ,黑长臂猿的分布区已不足1000Km2 ,总数量约1000只 ,为高度濒危的灵长类动物。造成黑长臂猿濒危的主要原因是 :热带和南亚热带原始森林的被破坏和缩小、人类活动的干扰使生境破碎和恶化、过度猎捕和长臂猿自身的生物学弱点。目前 ,中国的黑长臂猿已在 9个自然保护区中得到保护。  相似文献   

17.
The vegetative organization and reproductive development of Gracilariopsis lemaneiformis (Bory) Dawson, Acleto et Foldvik [including Gracilaria sjoestedtii Kylin] were investigated. Our observations on spermatangial development and post-fertilization features establish that Gracilariopsis Dawson is distinct at the generic level from Gracilaria Greville, and ice propose the resurrection of Gracilariopsis Dawson as a result. Spermatangial parent cells of Gracilariopsis are superficial, initiated in pairs or groups of three by concavo-convex longitudinal and transverse divisions. Each spermatangial parent cell cuts off a single, colorless spermatangium distally by a transverse division. The female reproductive apparatus consists of a supporting cell that bears a two-celled carpogonial branch flanked by two sterile branches, as in Gracilaria. Likewise, up to six sterile cells fuse with the carpogonium after fertilization to produce a primary fusion cell that generates the gonimoblasts; however, a secondary fusion cell is absent. Inner gonimoblast cells unite with cytologically modified cells of the inner pericarp by means of secondary pit-connections. Tubular nutritive cells are absent. The gonimoblast consists of a central sterile tissue interconnected throughout by secondary pit-connections surmounted by a fertile layer composed of carposporangia aligned in straight chains. The distribution of Gracilariopsis is extended to Western Europe.  相似文献   

18.
Longman's beaked whale, Indopacetus pacificus , was known previously from only two skulls. Here we describe four new specimens of this species from strandings in the western and central Indian Ocean. Two juveniles, previously misidentified from external morphology as Hyperoodon planifrons , were identified as I. pacificus through diagnostic characteristics of mitochondrial (mt) DNA sequences derived from the holotype of this species. Images of the external appearance and teeth of the species are presented for the first time. Comparison of the color pattern of these new specimens with that of "tropical bottlenose whales" sighted in the tropical Indian and Pacific oceans confirm that those unidentified whales represent I. pacificus. Moore (1968) erected a new genus, Indopacetus , for this species (described initially as Mesoplodon pacificus ) based primarily on cranial morphology. Phylogenetic analyses of short mtDNA fragments available from the specimens known to date were unable to resolve the validity of this genus. However, the diagnostic osteological features highlighted by Moore (1968) for Indopacetus were also observed in the new specimens. Rib count and number of fused cervical vertebrae may also be diagnostic. Rostrum depth at mid-length and melon shape further distinguish this species from Mesoplodon beaked whales. As such, we see no reason on morphological grounds to overturn Moore's (1968) proposal that Longman's beaked whale is sufficiently distinct to be afforded its own genus.  相似文献   

19.
根据采自全国20个省、自治区的盔孢伞属Galerina真菌标本整理、鉴定,确认出36种,其中包含28个已知种和8个中国新记录种。对中国新记录种褐柄盔孢伞G. badipes、帆孢盔孢伞G. calyptrata、迦佩盔孢伞G. jaapii、假拟提灯藓盔孢伞G. pseudomniophila、沼泽盔孢伞G. paludosa、泡孢盔孢伞G. physospora、萨列里盔孢伞G. sahleri和胫囊盔孢伞G. tibiicystis进行了详尽的形态学描述,提供了原生态照片和显微特征线条图以及分亚属、分种检索表。通过相关研究材料进行DNA提取,所得21条ITS序列与73条下载序列利用贝叶斯法及最大似然法构建系统发育树,验证鉴定结果的准确性。  相似文献   

20.
刘志琦  杨集昆 《昆虫学报》1998,41(-1):186-193
该文论述了我国北方粉蛉7种,其中卷粉蛉属Helicoconis及污褐卷粉蛉Helicoconis (Helicoconis)lutea为中国新记录,另包括粉蛉属Cxraiopteryx北方粉蛉Coniopteryx(Coniopteryx)arctica sp.nov,、周氏粉蛉Coniopteryx(Oniopteryx)choui,sp.nov.、宽带粉蛉Oniopteryx(Coniopteryx)vittiformis,sp nov.3新种及圣洁粉蛉Coniopteryx Coniopteryx)parthenia(Navas & Marcet,1910)、蒙干粉蛉Coniopteryx(Xeroconiopteryx)mongolica Melnander、爪干粉蛉Onioptery(Xeroconiopteryx)unguigonarcuata Aspock & Aspock 3中国新记录种。  相似文献   

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