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1.
The common intertidal barnacle Tetraclita squamosa occurs in two morphologically and genetically distinct forms in East Asia. The north-western Pacific form (Japan, Okinawa and Taiwan) has green parietes and the tergo-scutal flaps are black without any patterns. The south China form (Xiamen, Hong Kong) also has green parietes but the tergo-scutal flaps are black with two white spots on the tergal and scutal margin. Compared to the NW Pacific form, the south China form has a beaked tergum, a sharper tergal spur and cirrus I lacks serrulate type setae that have four rows of setules. The two forms differ by 15–16% in COI divergence, which is comparable to values for other congeneric barnacle species. The 12S rRNA and ITS1 sequences are also distinct between the two forms. Our results support the conclusion that the two forms are genetically differentiated species. We describe the NW Pacific form as a new species, Tetraclita pacifica . We are treating the other species as Tetraclita squamosa based on the fact that Pilsbry, in 1916, redescribed T. squamosa squamosa using samples collected from south China and the Philippines. Further studies are needed to confirm the identity and geographical distribution of the 'widely distributed' T. squamosa in the Indo-West Pacific.  相似文献   

2.
The tropical barnacle Tetraclita forms a belt on hard substrates in the intertidal zone of the Red Sea. Based on morphological data, three distinct species were suggested to exist, occupying different vertical levels - T. barnesorum, T. rufotincta and T. achituvi. In this study we used molecular (12S mitochondrial ribosomal DNA) and ecological data to examine whether this morphological variability reflects genetic differences, or is a result of environmental factors. Adults and spats, collected from settlement plates, were censused and screened genotypically using single strand conformation polymorphism (SSCP) analysis, and settlement dynamics was recorded. We provide evidence for the existence of only two distinct species, and point out both phenotypic plasticity and convergence within and between the proposed species. Cyprids of T. achituvi settle specifically at the lower part of the Tetraclita belt, and feature one phenotype. In contrast, T. rufotincta, occupying the upper and middle portions of the Tetraclita belt, settles throughout the range, shows phenotypic plasticity (three variants), and presumably undergoes selection at the lower part. Thus, the vertical zonation of Tetraclita is produced by the combination of pre-settlement and post-settlement factors, in T. achituvi and T. rufotincta, respectively. The examined system may offer a model in which to study the mechanisms underlying sympatric speciation.  相似文献   

3.
Five new species of Antillean bees are described and illustrated: Colletes granpiedrensis n. sp. (Cuba) (Colletidae) is characterized as follows: Head and mesosoma black, legs and metasoma brown. Dense brown hairs on head and mesosoma; white on frons and metasomal terga. Clypeus, frons and mesosoma with large punctures, lesser on vertex and metasoma. Malar space more wide than long. Male and female slightly similar, except in the apical margin of clypeus, supraclipeal area, and color of the pubescence on legs and sterna; Osmia (Diceratosmia) stangei n. sp. (Dominican Republic) (Megachilidae) is characterized as follows: Dark metallic green, metasoma black with metallic green reflections. Pubescence light; body with large, closed punctures. Female with violet reflections in tergum III and mandible tridentate; Coelioxys (Cyrtocoelioxys) alayoi n. sp. (Cuba) (Megachilidae) is characterized as follows: Female black, except basal area of mandibles, tegula, legs, lateral area of tergum I and sterna, reddish brown. Posterior margin of scutellum rounded. Apex of tergum VI with spine curved up. Sternum VI fringed with short, closed setae, and the apex with short spine; Coelioxys (Boreocoelioxys) sannicolarensis n. sp. (Cuba) (Megachilidae) is characterized as follows: Black, except antenna and tegula brown; legs and sterna reddish brown. Clypeal margin straight in profile. Gradular grooves on metasomal terga II and III distinct medially. Fovea on metasomal tergum II of male deep and short, and Triepeolus nisibonensis n. sp. (Dominican Republic) (Apidae) is characterized as follows: Dorsal pubescence (short and dense) on mesosoma and metasoma from white to yellow, according to specimen; ventral pubescence white. Tergal bands of hairs interrupted medially; two spots of light pubescence on tergum II. Male metasomal sternum VII with anterior margin V-shaped and basal constriction narrow.  相似文献   

4.
The microstructure and chemical composition of the calcite shell of the sea barnacle Tetraclita rufotincta (Pilsbry, 1916) were investigated using microscopic and analytical methods. The barnacle shell was separated mechanically into its three substructural units: outer, interior, and inner layers. The organic matrices of these structural parts were further separated into soluble and insoluble constituents and their characteristic functional groups were studied by FTIR. Investigation of the mechanical properties of the interior mass of the shell reveals remarkable viscoelastic behavior. In general, the mechanical behavior of the shell is a function of its geometry as well as of the material, of which it is constructed. In the case of T. rufotincta, as calcite is a brittle material, the elastic behavior of the shell is apparently related to its micro- and macroarchitecture. The latter enables the shell to fulfill its primary function which is to protect the organism from a hostile environment and enables its survival. Our detailed identification of the similarities and differences between the various structural components of the shell in regard to the composition and properties of the organic component will hopefully throw light on the role of organic matrices in biomineralization processes.  相似文献   

5.
Weifang Shi  Xiaoli Tong 《ZooKeys》2015,(478):129-137
A new species of Baetidae, Gratia baibungensis sp. n., is described and illustrated based on nymphal stage collected from the southeastern Tibet (Xizang) and the genus is reported for the first time from China. This new species can be readily differentiated from its congeners by the absence of a protuberance on the posterior margin of the abdominal tergum X, glabrate simple submarginal setae on the labrum, and the posterior margin of sterna VI–IX having much longer spatulate setae.  相似文献   

6.
This study about the faluns of Touraine modifies our knowledge on the distribution of the Middle Miocene Cirripedes. So, the occurrence of Megabalanus tulipiformis in these faluns is confirmed and that of Balanus amphitrite is refuted. The discovery of representative members of Tesseropora allows the reevaluation of the palaeobiogeography of this genus. A new species of Balaninae, Fistulobalanus ligeriensis is described, which possesses: parietes of the wall plates with secondary inner lamina and primary tubes transversally septed; sheath vesicular; radii medium to broad; tergum with no deeply excavated basal margin on carinal side of spur, spur width greater than spur length and greater than distance from spur to basiscutal angle, spur furrow open. Besides, the occurrence of Megabalanus dollfusi in the Red Crag of England (Plio-Pleistocene) is established.  相似文献   

7.
Exposure to wave action and other environmental factors can alter the morphology of intertidal barnacles. We tested several hypotheses on the causes of morphological variation in the cirri and penises of the barnacle Tetraclita stalactifera at sites differing in wave exposure, at different heights in the intertidal zone, and at different levels of population density. Unlike many other acorn barnacle species, cirrus and penis characteristics did not correspond to differences in wave exposure or crowding. However, barnacles from higher tidal elevations had thicker cirri and thicker penises than those from lower elevations. Because of reduced time submerged at higher elevations, increased thickness may be a means of compensating for reduced feeding and mating opportunity by allowing for continued feeding and mating attempts during periods of greater wave action. Our observations of differences in cirrus and penis morphology suggest that phenotypic plasticity in penis and cirrus characteristics are adaptations shared by the species T. stalactifera and other acorn barnacles, but that T. stalactifera responds differently to environmental stimuli than do other species.  相似文献   

8.
A new species, Ctenophthalmus (Euctenophthalmus) parthicus sp. n., is described from social vole (Microtus socialis Pallas) from four localities of the West Kopetdag Mountains of Turkmenia. The new species is close to C.(E.) secundus Wagner and C.(E.) congener nadimi Farhang-Azad. It differs from males of the other known species by the following characters. The movable process has an infra-acetabular process whose length is the same as the height of its supra-acetabular portion. The movable process has the straight front margin, right anterior apical angle. The anterior part of the dorsal margin of the movable process is elevated, the hind part is slightly concave. The posterior apical angle of the movable process is cut. The hind margin of the movable process is convex. The apex of the distal arm of sternum IX is straight, not oblique. The female differs by the following peculiarities. Sternum VII has a well developed dorsal lobe below which there is a smaller rounded lobe and a distinct small ventral process. Unciform sclerotization of tergum VIII (or the place of connection between tergum VIII and its internal lobe) resembles an arc. The front margin of the internal lobe of tergum VIII is not sclerotized. The bursa copulatrix is as long as the dorsal spines of pronotum.  相似文献   

9.
记述革板螨属3新种和派伦螨属1新种:井冈山革板螨Gamasholaspis jinggangshanensis sp.nov.,何氏革板螨Gamasholaspis hochyicheni sp.nov.,新阿革板螨Gamasholaspis novakimotoi sp.nov.和沙县派伦螨Parholaspulus shaxianensis sp.nov.  相似文献   

10.
The invertebrate collection of the Australian Museum revealed the existence of three new species of the genus Uromunna (family Munnidae) from New South Wales, Australia. Uromunna tenagoika sp. nov. from Batemans Bay has the head anterior margin concave, without simple setae; eyes with few ommatidia, eye lobes with both margins parallel, in male posterior margin directed forward; pereonite 7 as wide as pereonite 6, subequal to pleotelson width; pleotelson distal margin pointed, suburopodal shelf present; mandible palp absent; pereopod I propodus robust setae absent; pereopods relatively short; pleopod IV exopod distal tip with one pappose seta. Uromunna rhamnda sp. nov. from Batemans Bay has a head anterior margin concave, without simple setae; eye lobes with both margins parallel, in male posterior margin parallel to frontal margin; pleotelson distal margin pointed, suburopodal shelf absent; mandible palp present; pereopod I propodus robust setae absent; pleopod IV exopod distal tip with one pappose seta. Uromunna eora sp. nov. was found at Southern Creek, located north of Sydney and is the first species of the genus described from a fully freshwater environment with no marine water input. It has a relatively elongate body (length 3.4× width), anterior margin concave, eye lobes with both margins converging distally, in male posterior margin directed forward; pereonite 7 as wide as pereonite 6, wider than pleotelson width; pleotelson distal margin truncate, suburopodal shelf present; mandible palp present; pereopod I propodus robust setae present; pleopod IV exopod distal tip with two pappose setae. This work raises the number of Uromunna species found in Australia to a total of six.

http://zoobank.org/urn:lsid:zoobank.org:pub:D877FC47-BC6E-4827-BA89-3A75AFDE1124  相似文献   


11.
马立名 《蛛形学报》2012,21(1):12-16
记述寄螨属1新种:棒毛寄螨Parasitus clavasetosus sp.nov.和新革螨属1新种:丛枝新革螨Neogamasus fasciculus sp.nov.  相似文献   

12.
Marine phytoplankton samples containing diatoms of the Chaetoceros socialis group were collected from Thailand, China, Denmark, and Greenland, and cells were isolated into culture for light and electron microscopy and DNA sequencing of D1–D3 of the LSU rDNA. Species of this lineage are characterized by three short and one long setae extending from each cell, the long setae from several cells joining into a common center to form large colonies, which are sometimes visible with the naked eye. Phylogenetic analyses including sequences from other parts of the world revealed segregation into three groups. Most sequences fell into two large clades, one comprising material from cold waters, whereas the other contained material from warmer waters. Strain CCMP 172 from the Strait of Georgia, Washington State, USA, formed a separate group. The warm‐water species included Chinese and Thai material and therefore probably also material from the type locality of C. socialis, Hong Kong. It is characterized by all setae being covered by spines and the setae extending from the valve at some distance from the margin. In the resting spores, both valves are ornamented with spines. The cold‐water material is characterized by three spiny and one mostly smooth long setae, and the setae extend from the valve near the margin. Both valves of the resting spore are smooth. This material is described as C. gelidus sp. nov. C. radians, described from the Baltic in 1894, is considered a synonym of C. socialis. CCMP172 is in many ways intermediate and probably constitutes a separate species. The published evidence on this globally distributed and sometimes bloom‐forming group of species indicates higher species diversity than presently thought.  相似文献   

13.
Two new species of Tubificoides are described from the west coast of Florida. Both species have large lateral openings of the penis sheaths with proximal flap-like projections. Tubificoides pollex sp.n. is characterized by (1) papillate body wall in postclitellar segments; (2) possession of hair and bifid setae anteriorly, and only bifid setae in pcstclitellar segments; and (3) conical penis sheaths with a lateral opening and a flap-like projection on the proximal margin. The setal distribution of the new species is similar to that of T. bakeri Brinkhurst, 1986, which is redescribed on the basis of new material. Tubificoides lunatus sp.n. is similar to T. pollex except that the flap-like projections of the penis sheaths are crescent shaped, all the somatic setae are bifid, and body wall papillae are absent. Records of Tubificoides brownae Brinkhurst & Baker, 1979, and T. imajimai Brinkhurst, 1986, from the Gulf of Mexico and Caribbean, respectively, are also presented. The latter species was previously known only from subtropical regions of Japan and the People's Republic of China.  相似文献   

14.
15.
Pandher MS  Saini MS 《ZooKeys》2011,(152):71-86
The genus Kisaura Ross, 1956 (Trichoptera, Philopotamidae, Philopotaminae) is reported from India the first time. Six new species are described and illustrated: Kisaura elongatasp. n., Kisaura eloctsp. n., Kisaura clavatasp. n., Kisaura gangtokensissp. n., Kisaura truncatasp. n., all from Gangtok (Sikkim) and Kisaura himachalicasp. n. from Barot (Himachal Pradesh). Male genitalia of this genus are distinguishable from those of other genera of the family by the pair of long lateral processes of tergum X, the well-developed mesoventral plates between two segments of the inferior appendages, and by the brush-like row of dark setae on the inner surfaces of the terminal segments (harpago) of the inferior appendages.  相似文献   

16.
17.
记述派伦螨属1新种:遵义派伦螨Parholaspulus zunyiensis sp.nov.和革板螨属1新种:江西革板螨Gamasholaspis jiangxiensissp.nov.,并描述都匀革板螨Gamasholaspis duyunensis Chen,Guo et Gu,1994雄螨.  相似文献   

18.
记述采自中国陕西佛龙的瘤(虫责)属Tyloperla 1新种:双凹瘤(虫责)Tyloperla bihypodroma Du, sp. nov.,该种与尖突瘤(虫责)Tyloperla attenuata很相近,但前者第8背板近后缘形成1个隆起脊、其中部有1凹陷,后者则在背板中部形成1近圆形的隆起、其上的锥状感觉器比前者多;前者第9背板中央微凹、其前缘骨化明显、极小的锥状感觉器稀少,后者中部有1丛明显的锥状感觉器;前者翅透明,后者翅微烟褐色.新种的模式标本保存在扬州大学昆虫标本馆.  相似文献   

19.
Four new species of Cyclopoida from deep-sea waters are described and placed in two new genera: Giselina gen. n. and Sensogiselina gen. n. The new genera and species belong to a new monophyletic group within the cyclopinid cyclopoids. A new name, Giselinidae, is proposed for this monophylum. The new family is characterised by the combination of the following characters: (1) tergite of leg 1 fused to cephalosome dorsally, but incompletely fused laterally, (2) absence of aesthetascs on ancestral antennulary segments XVI, XXI and XXV, (3) absence of antennary exopodal setae, (4) presence of only three spines on distal exopodal segment of leg 1, (5) absence of inner setae on first endopodal segments of legs 1–4, (6) outer terminal and distal inner elements of distal endopodal segment of leg 4 transformed into spines, (7) distal outer element of leg 5 exopod transformed into a spine, (8) leg 6 with only one seta, and (9) furcal setae I and III located on dorsal margin. Received in revised form: 16 June 2000 Electronic Publication  相似文献   

20.
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