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1.
Evolutionary relationships among seven species from two genera ( Pantinonemertes and Geonemertes ) of terrestrial nemerteans (phylum Nemertea) were estimated by a Wagner analysis of 27 morphological, ecological and life history characters. Pantinonemertes was found to be a paraphyletic taxon, and it is suggested that this genus should be combined with Geonemertes to form a monophyletic group. A previous hypothesis for how terrestrial nemerteans evolved is discussed and compared to the results of the cladistic analysis. This suggests that terrestrial and semi-terrestrial species evolved from a marine ancestor; the upper littoral and marine environments have been recolonized by descendants from a terrestrial ancestor.  相似文献   

2.
Ray  Gibson  Janet  Moore  Frank B.  CRandall‡ 《Journal of Zoology》1982,196(4):463-474
A new species of semi-terrestrial monostiliferous hoplonemertean from California, Pantinonemertes californiensis sp. nov., is described and illustrated. The genus Pantinonemertes, transitional between marine and terrestrial habitats, provides evidence for one evolutionary line towards the colonization of land by nemerteans.  相似文献   

3.
Kajihara  Hiroshi  Gibson  Ray  Mawatari  Shunsuke F. 《Hydrobiologia》2001,456(1-3):187-198
A new genus and species of monostiliferous hoplonemertean, Diopsonemertes acanthocephala gen. et sp. nov., is described from Otsuchi Bay, Japan. Significant anatomical features of the new form include a body wall longitudinal musculature anteriorly divided into inner and outer layers by connective tissue, no pre-cerebral septum, the presence of a thin coat of diagonal muscle fibres between the body wall longitudinal and circular muscle layers in the foregut body region, cephalic retractor muscles derived only from the inner portion of the divided longitudinal muscles and a rhynchocoel more than half the body length.  相似文献   

4.
Moore  Janet  Gibson  Ray  Jones  Hugh D. 《Hydrobiologia》2001,456(1-3):1-6
The present paper records changes in the reported distribution and abundance of terrestrial nemerteans during the last 30 years. New records are reported from the Isles of Scilly, Bermuda and New Zealand of species previously only known elsewhere. Human activity, especially the increased importation and exportation of plants between countries, has probably led to terrestrial nemerteans, as well as other organisms, becoming introduced into many new localities. However, the conservation outlook is not hopeful because of a global loss of appropriate habitat, particularly forests. Today three species (Geonemertes rodericana Gulliver, 1879, Pantinonemertes agricola Willemoes-Suhm, 1874 and Antiponemertes allisonae Moore, 1973) are feared to be extinct, and none of the extant species seem to be as abundant as they once were. Behavioural changes in Antiponemertes pantini (Southgate, 1954) under arid conditions may be associated with heavy gregarine infestations.  相似文献   

5.
Three species of marine nemerteans described and illustrated from Queensland and the Great Barrier Reef, Australia, include one new genus and two new species: these are the monostiliferous hoplonemerteans Thallasionemertes leucocephala gen. et sp. nov. and Correanemertes polyophthalma sp. nov. A new colour variety of the heteronemertean Micrura callima is also reported, this species previously only being known from Rottnest Island, Western Australia. A key for the field identification of the marine nemerteans recorded from coastal Queensland and the Great Barrier Reef is provided.  相似文献   

6.
Seven new species of Paramunnidae from the Magellan Strait are described, two of which are placed in new genera: Paramunna magellanensis sp. nov., P. menziesi sp. nov., P. parasimplex sp. nov., P. patagoniensis sp. nov., Allorostrata ovalis gen. et sp. nov., Austrosignum dentatum sp. nov., and Magellianira serrata gen. et. sp. nov. Four known paramunnid species from the same location are redescribed: Parammunna integra, P. simplex, P. subtriangulata and Munnogonium tillerae . While investigating the genus Paramunna , two species of this group, Acutomunna foliacea (Chardy, 1975) gen. nov. and Paramunna foresti Carvacho , 1977 were removed, which involved the erection of a new genus. The allocation of P. foresti remains uncertain. Some diagnostic characters of the Paramunnidae and a key to the Magellanic species of Paramunna are presented.  相似文献   

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8.
Two new lineid heteronemerteans, Kirsteueria abocellus gen. et sp nov. and Parborlasia hutchingsi sp. nov., from Sydney, New South Wales, are described and illustrated. The systematic relationships of these nemerteans are discussed and a key is provided to the known species of Parborlasia.  相似文献   

9.
The diatom family Rhaphoneidaceae is characterized by high generic diversity and low species diversity with most genera known to have long stratigraphic ranges. The genera within this family are neritic marine, and mostly epipsammic. A new modern and epipsammic genus, Meloneis gen. nov., is described herein and is compared to all genera within Rhaphoneidaceae and especially to Rhaphoneis Ehrenberg s.l. Within Meloneis three new species and one variety are distinguished and described herein: M. mimallis sp. nov., M. mimallis var. zephyria var. nov., M. akytos sp. nov., and M. gorgis sp. nov.  相似文献   

10.
The discovery of new species, a study of the type material of already described species and an analysis of the literature data call for an extensive rearrangement of the Family Tethyidae, whose last revision dates from Burton (1924). The rearrangement proposed here attributes to the Family eight genera: Tethya Lam. (type genus), Burtonitethya gen nov. , Columnitis Schmidt, Halicomeies Topsent, Stellitethya gen. nov., Tectnitethya gen. nov., Tethycometes gen. nov . and Xenospongia Gray. The genus Aaptos is excluded from the Tethyidae. Three of the new genera have been established for species previously attributed to the genus Tethya and two are new: Burtonitethya gemmiformis (Burton & Rao) and Tethycometes sibogae sp. nov . Five species, previously attributed to Tethya , are considered 'incertae sedis'. An analytical key and discussion of the evolution of the family are included.  相似文献   

11.
Freshwater nemerteans   总被引:3,自引:0,他引:3  
The freshwater hoplonemertean genus Prostoma is critically reviewed and revised and a new species Prostoma kolasai sp. nov., is described. All the freshwater nemerteans of the world are compared and contrasted, with reference to those common morphological characters which may be related to the colonization of freshwater habitats. A key to the world freshwater nemerteans is provided.  相似文献   

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13.
Shichun  Sun  Jingrang  Lu 《Hydrobiologia》1998,367(1-3):175-187
A new genus and species of heteronemertean, Yinia pratensis gen. nov. and sp. nov., collected from low salinity waters (salinity 0.2–0.4 ‰) at Changjiang River Estuary, is described and illustrated. The species possesses a proboscis with an outer circular and an inner longitudinal muscle layer, and is placed in family Lineidae sensu Gibson. The following combination of morphological features distinguishes the new species from any other genera in this family: proboscis with two muscle crosses; dermis without connective tissue layer between gland cells and body wall outer longitudinal muscle layer; rhynchocoel wall circular muscles not interweaving with adjacent body wall longitudinal muscles; foregut with circular somatic muscles and subepithelial gland cell layer; neurochord cells present in central nervous system; caudal cirrus missing; blood system developed into alimentary plexus extending almost the full length of the body. Another significant character is that the lobular excretory cells are extremely well developed which may represent adaptation to water of low salinity. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

14.
A new genus Amblomma gen. nov. of fossil beetles is erected and can be assignedto the family Ommatidae because its two procoxal cavities are contiguous and the articulations of the abdominal ventrites are abutting. The new genus is similar to Zygadenia Handlirsch, 1906 (=Notocupes Ponomarenko, 1964), Tetraphalerus Waterhouse, 1901,Rhobdocupes Ponomarenko, 1966 and Sinocupes Lin, 1976, but can be distinguished from other genera according to the following characters: the second segment of antennae is shorterthan the third one in length; the posterior tarsi with the basal segment is obviously shorter than the three following taken together in length; the antennae reach the posterior ridge of prothroax in length, and the sides of the prothroax with serrulate margin. Four new species of the new genus are described and figured: Amblomma psilata gen. et sp. nov., Amblomma rudis gen. et sp. nov., Amblomma epicharis gen. et sp. nov., and Amblomma stabilis gen. etsp. nov. A key to species within this new genus is provided. All the specimens are collected from the Late Jurassic Yixian Formation of western Liaoning and are now housed in the College of Life Science, Capital Normal University, Beijing, China.  相似文献   

15.
Small gastropods from the Jurassic deposits of the European Russia, united into the lower Heterobranchia or Allogastropoda, are described. The families of Ampezzanildidae, Cimidae, Cornirostridae, Ebalidae, and Stuoraxidae are distinguished, and a set of taxa is given without reference to a definite family. The family Ampezzanildidae from the Jurassic deposits is described for the first time on the basis of the mass material, ascribed to the new genus Zizipupa gen. nov. with the sole species of Z. costata sp. nov. The family Cimidae includes the genera of Cristalloella, Rotfanella, Urlocella, and Unzhispira gen. nov. with species C. spiralocostata (Gründel, 1998), R. gerasimovi sp. nov., R. reticulata sp. nov., Urlocella undulata sp. nov., and Unzhispira minuta sp. nov. The genus Heteronatica gen. nov. is included into the family Cornirostridae. This genus is the first siphonostomatous representative of the given family including the sole long-living species H. globosa sp. nov., which is subdivided into subspecies H. globosa globosa and H. globosapromota subsp. nov. The family Ebalidae is represented by the genus Ebala, shells of which are distributed from the Middle Oxfordian to the Middle Volgian. The family Stuoraxidae is described based on two genera Stuoraxis and Aneudaronia gen. nov., including species of S. crassa sp. nov. and A. elegans sp. nov. The genus Doggerostra, which fits into different families of Heterobranchia in terms of shell morphology is represented by the species D. riedeli Gründel, 1998, which was previously known from the Bathonian and Callowian deposits in Poland and Germany, as well as form the Upper Jurassic interval in the Russian Plate. The Middle Volgian subspecies D. riedeli affinis subsp. nov. is distinguished in the composition of this species. In addition, the genus Masaevia gen. nov. with the sole species of M. sinistra sp. nov. is described. Due to so specific shell morphology of this genus, its position in the Heterobranchia system is unclear. It is not improbable that we deal with small planktonic gastropods of protoconchs of unknown group of planktonic or benthic gastropods.  相似文献   

16.
In this paper, five new pollen genera and twenty new pollen species of angiospermae from the Late Cretaceous of a certain basin in central China are described. Four new organ genera and their species include: Morinoipollenites normalis gen. et sp. nov., Morinoipollenites minor gen. et sp. nov., Morinoipollenites polyprojectus gen. et sp. nov., Morinoipollenites rhombiformis gen. et sp. nov., Jianghanpollis ringens gen. et sp. nov., Jianghanpollis, mikros gen. et sp. nov., Jianghanpollis radiatus gen. et sp. nov., Jianghanpollis sayangensis gen. et sp. nov., Jianghanpollis arciformis gen. et sp. nov., Myoporumpollonites variabilis gen. et sp. nov., Myoporumpollenites striatus gen. et sp. nov., Lythraites giganteus Yu, Guo et Mao gen. et sp. nov. Lythraites clavatus sp. nov., Lythraites dilutus sp. nov., Lythraites magnus sp. nov., Lythraites varrustriatus sp. nov., Lythraites pachyrrhachis sp. nov.; the new-form genus and its species are: Crassimarginpollenites reticulatus gen. et sp. nov., Crassimerginpollenites mirus gen. et sp. nov., Crassimarginpollenites psilatus gen. et sp. nov. The new pollen genera and their species described herein have been compared in some details with recent pollens and considered their affinity with such recent families as Dipsacaceae, Myoporaceae, Apocynaceae and Lythraceae. According to the age of the pollen-bearing strata, a preliminary discussion is made regarding to the taxonomy of the recent plants families with which our new described pollens are related. Hence, this study may provide some mieropalaeobotanical information for deciphering 'the phylogeny of these plants.  相似文献   

17.
A new genus, Asiaontsira gen. nov., and two new species, A. cucphuongi sp. nov. (type species) and A. cantonica sp. nov., are described from tropical and subtropical areas of South‐East China and North Vietnam. This genus is compared to the closely related Australian Ontsirospathius Belokobylskij, Iqbal and Austin, 2004 as well as the similar and almost cosmopolitan genus Ontsira Cameron, 1900. A key to both species of Asiaontsira gen. nov. is provided.  相似文献   

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20.
中国食蚜蝇科一新属二新种记述(双翅目,食蚜蝇科)   总被引:1,自引:1,他引:0  
作者于2002年在秦岭山区进行食蚜蝇科昆虫调查时,发现食蚜蝇科昆虫1新属2新种,记述如下.新种模式标本保存于陕西理工学院陕西省资源生物重点实验室标本馆.平背食蚜蝇属,新属Lamellidorsum gen.nov.复眼裸,颜面及额黄色,面中突小而钝圆.触角黄色,第3节近圆形.胸部背面黑色,具青铜色光泽,两侧暗黄色.小盾片黄色,至少两侧前角被黄毛,中胸上前侧片前低平部缺直立长毛,腹侧片上、下毛斑全长宽的分开.后胸腹板裸,后足基节后腹端角缺毛簇.翅面被微毛,无裸区,翅后缘具一列间隔均匀的骨化黑色小点.腹部狭长,两侧近平行,第3、4背板前部具宽黄带.雄性背针突侧面观近三角形,舌状突顶端尖,与侧臂等长.上叶呈半月形.阳茎端背面平且向两侧扩展呈方形,两侧近端部收缩.阳茎基的腹侧侧扁,后端下部向两侧略扩展.模式种:黄毛平背食蚜蝇,新种Lamellidorsum piliflavum sp.nov.新属近似于狭腹食蚜蝇属Meliscaeva Frey及美蓝食蚜蝇属Melangyna Verrall.与前者的区别是中胸上前侧片前低平部无直立长毛,与后者的区别是翅后缘具一列间隔均匀的骨化黑色小点,腹部第3~4背板前部具宽黄带.雄性尾器不同.黄毛平背食蚜蝇,新种Lamellidorsum piliflavum sp.nov.(图1~7)雄性头部半球形.头顶黑色,被暗黄色毛,单眼三角被黑毛.额暗黄色,基部覆黄粉,被黑毛,中部被黄毛,额角约50°.颜面暗黄色,覆黄粉及黄毛,面中突小而圆,裸.颊部暗褐色,被黄毛.触角暗黄色,第3节长约等于其高,端部宽圆,触角芒棕黄色裸,基部1/3较粗,被微毛,端部约2/3细.中胸背板黑色,具青铜色光泽,两侧暗黄色,被棕黄色毛,小盾片黄色,被黄毛,盾下缨密,棕黄色.胸部侧板黑色,中域覆灰粉,被暗黄色毛.中胸上前侧片前低平部缺直立长毛,腹侧片上、下毛斑全长宽的分离.后胸腹板裸,后足基节后腹端角缺毛簇.足主要棕黄色,被黄毛.翅面被微毛,痣棕黄色,翅后缘具一列间隔均匀的骨化黑色小点.腹部两侧平行,黑色.第2背板两侧具长三角状黄斑.第3背板基部具宽黄带,长大于背板长的2/3.第4背板基部黄带约为背板长的1/2,背板后缘具黄边.第5背板黄色.露尾节黑色.第1背板被棕黄色毛,第2、3背板被毛同底色,第4背板及其后部各节被黑毛,第4背板黄带两侧被黄毛.雄性尾器,暗黑色.尾须黄色,被黄毛.第9背板暗黑 色.背针突暗黑色,被灰白色毛,角钝圆,腹侧缘及内侧表面端部被短刺毛,外侧表面中央略下陷,外表面的内侧部平,呈半月形.第9腹板舌状突发达.上叶半月形,背侧及后侧黑色,外表面顶端有狭缝.阳茎端背面平且向两侧扩展呈长方形,两侧近端部收缩.阳茎基的腹侧侧扁,后端下部向两侧略扩展.阳茎表皮内突左右侧扁.雌性 未知.♂体长9.5mm,翅长8.0mm.正模♂,2002-09-01,陕西眉县(红河谷,海拔1000 m),霍科科采.黑毛平背食蚜蝇,新种Lamellidorsum pilinigrum sp.nov.(图8~11)雄性 未知.♀体9.5mm,翅长8.0mm.正模♀,2002-09-01,陕西眉县(红河谷,海拔1000m),霍科科采.新种与黄毛平背食蚜蝇近似,但其小盾片被黑毛,第2背板具黄带,黄带中央具三角形黑斑,后端不达黄带后缘,后足腿节及胫节中部黑褐色.  相似文献   

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