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1.
Here we present morphometrical evaluation, biogeographical distribution patterns and ecological information for five coccolithophore taxa (Calcidiscus leptoporus, C. leptoporus small, C. quadriperforatus, Umbilicosphaera foliosa and U. sibogae). This information is based on data obtained from surface sediments from the South Atlantic. The three Calcidiscus taxa can easily been distinguished by a combination of size and qualitative characters of their distal shields. Mostly encountered in the temperate to sub-polar regions C. leptoporus is the most abundant taxon and exhibits a negative correlation to temperature and salinity. Both, C. leptoporus small and C. quadriperforatus reach their maximum abundances also at higher latitudes and in the SW-African upwelling area. Their distributions therefore suggest preference for nutrient-enriched waters, which is also indicated by CCA. The two circular Umbilicosphaera species exhibit significant differences in coccolith morphology and show little overlap in size. Highest abundances are encountered in sub-tropical latitudes and are mainly derived from U. sibogae. In contrast, U. foliosa is present in very low abundances. Both species exhibit a preference for warm and oligotrophic conditions. However, U. foliosa increases in relative proportion to U. sibogae at the southernmost locations and in the Benguela upwelling. This could be interpreted as an affinity for slightly cooler and nutrient-enriched environments.  相似文献   

2.
The nudibranch Phestilla sibogae feeds only on corals of the genus Porites. The nudibranch's minute (∼ 200 μm) larvae are specifically induced to settle and metamorphose by a chemical cue released by the coral, causing the larvae to recruit to reefs composed predominantly of Porites compressa. In this study, we investigated temporal and spatial patterns of recruitment of P. sibogae into coral reefs in Kane?ohe Bay, HI. We collected heads of P. compressa at 3-week intervals for 3 years, brought them to the laboratory and maintained them in aquaria fed with filtered seawater for 2 weeks, and then examined them for the presence of juvenile P. sibogae that had grown large enough to be seen. We found that P. sibogae recruits to the Porites reefs of Kane?ohe Bay sporadically and unpredictably throughout the year. Although most coral samples contained no or very few P. sibogae, three periods of intense recruitment (90-450 juvenile P. sibogae kg− 1 of coral) were recorded, all in different seasons. Size-frequency analysis of recruits on the coral revealed high rates of post-settlement mortality in the field, most likely due to predation. Given the short pre-competent larval period of P. sibogae, the low rate of flushing of Kane?ohe Bay and the patterns of recruitment observed, we conclude that this population of P. sibogae is essentially a self-recruiting one. Two of the sampled reefs were characterized by unidirectional flow, allowing us to test a model of transport of larvae of P. sibogae responding to dissolved coral cue in turbulent, wavy flow. The model predicts that more larvae will be transported into upstream portions of a reef than into downstream portions, a prediction confirmed by analysis of the field-recruitment data. Furthermore, field releases of larval mimic particles also showed that most mimics landed in the upstream areas of reefs and down among the bases of coral branches, rather than at their tips.  相似文献   

3.
The Oligocene Malembo locality, Cabinda exclave, Angola, has yielded a rich vertebrate fauna represented by fragmentary remains. This fossiliferous locality is the only definite occurrence of Oligocene terrestrial mammals in sub-Saharan West Africa. The hyracoids from Malembo have only been very succinctly described and compared thus far, so that their systematic attribution is not consensual among specialists. A revision now allows the identification of three (or four) medium to large-sized species represented by Geniohyus dartevellei, Pachyhyrax cf. crassidentatus, and two undetermined taxa. The species G. dartevellei is revived for the holotype of Palaeochoerus dartevellei Hooijer, 1963; this species is unique to Malembo but appears close to Geniohyus mirus, a species only known from the early Oligocene of the Fayum, Egypt. Other species of Geniohyus and Pachyhyrax crassidentatus are also only known from the early Oligocene of the Fayum. The presence of Geniohyus and Pachyhyrax cf. crassidentatus at Malembo thus supports an early Oligocene age for the fauna.  相似文献   

4.
Pentanchus profundicolus is an enigmatic shark, characterized by a single dorsal fin. The holotype, which was collected in 1909 from the Philippines, had remained the only known example of the species for 90 years. A second specimen, collected from the same waters, is re-described. The presence of a single dorsal fin remains equivocal in so far as it represents the normal condition for the species. Aspects of the species' relationship with the species ofApristurus are discussed.  相似文献   

5.
Peziza emileia Cooke and P. howsei Roze & Boud. are compared here; they are morphologically very similar, but the internal transcribed spacer (ITS) sequence is unique for each of the two species. Furthermore, since the holotype of P. emileia deposited in Kew (K) contains an unidentified fungus and the holotype of P. howsei in Paris (PC) no longer exists, we provide lectotypification and epitypification for both taxa.  相似文献   

6.
A new species of the pyralid moth, Pediasia sinevi Shodotova et Bolshakov, sp. n., is described from Central Yakutia (locus typicus—Bestyakh). This species is very similar to P. jucundella (Herrich-Schäffer, 1847) in color and pattern of the wings and also similar to P. truncatella (Zetterstedt, 1839) in the structure of the male genitalia. The holotype and paratype are deposited at the Zoological Institute, Russian Academy of Sciences (St. Petersburg).  相似文献   

7.
The holotype of the species Dolichopus sublimbatus Becker, 1917 is redescribed. Illustrations of the hypopygium of this species are given for the first time. A new species, Dolichopus kuznetsovi sp. n., is described from Primorskii Territory. A key to the species of the Dolichopus sublimbatus group is given.  相似文献   

8.
Cryptaulax? bittneri, also known asPromathildia bittneri, is frequently reported to be present in Late Triassic biotas and is cited as a species with almost cosmopolitan distribution (S-Alps, S-America, Iran, Karakorum). Re-examination of the holotype of the species shows that nearly all reports are based on misidentifications. This species is known only from the holotype and thus it is known only from its type locality, the Cassian Formation (S-Alps, Italy). Frequent misidentifications show thatCryptaulax bittneri is poorly known and therefore the holotype is figured and redescribed. It is one of the earliest cerithioid gastropods that has a complex teleoconch ornament typical of many modern Cerithioidea. This complex ornament of axial ribs and spiral cords with knobby intersections could represent an early aspect of the Mesozoic marine revolution. A complex teleoconch ornament and a carinated larval shell could represent apomorphies of the Mesozoic Procerithiidae, since these characters are absent in the known Palaeozoic Cerithimorpha. The Recent genusArgyropeza is so similar to the procerithiid genusCryptaulax thatArgyropeza can be considered to represent a living fossil.Xystrella inaequelineata Nützel &; Senowbari-Daryan 1999 from the Late Triassic Nayband Formation of central Iran is transferred toCryptaulax.  相似文献   

9.
A longitudinal section cut in the holotype of Michelinia compressaMichelin shows that this species belongs to the genus YavorskiaFomitchev.  相似文献   

10.
Information is presented about a finding of two specimens of a rare sea snake Leioselasma czeblukovi, which was known until now only from the holotype and a paratype, and also about the taxonomical position of the genus Leioselasma within the group of genera Hydrophis sensu lato and the species composition of the latter. An identification key for species is presented.  相似文献   

11.
Wm. Wayt Thomas 《Brittonia》1985,37(2):190-191
Thomas, Wm. Wayt (New York Botanical Garden, Bronz, NY 10458-9980). Simaba orinocensis, an earlier name for Simaba multiflora (Simaroubaceae). Brittonia 37: 190–191. 1985. Simaba orinocensis has been maintained as a species separate from S. multiflora because Kunth’s illustration showed the flowers to be very different from those of S. multiflora. Examination of the holotype reveals that its flowers do not resemble those illustrated by Kunth but are very similar to those of S. multiflora. Therefore, the two names are considered taxonomic synonyms with S. orinocensis having priority. A complete synonymy is given.  相似文献   

12.
A new species, Mosiera nipensis (Myrtaceae), from the crest of the Sierra de Nipe, Cuba, is described and illustrated. This species is readily distinguished from all other species of Mosiera by two diagnostic characters: four-angled, slightly four-winged young twigs, and calyx lobes that are valvate in the bud. We suspect that this species grows on a serpentine substrate. It is known only from the holotype, a collection made in 1941. An assessment of its conservation status is urgently needed.  相似文献   

13.
Hemiclepsis quadrata, which is the only representative of the genus so far reported in Africa, is redescribed. Illustrations showing the diagnostic features of the taxon are provided for the first time. A thorough study of the holotype and one of the paratypes, as well as additional specimens, revealed that Moore overlooked certain important taxonomic features when he described the leech as a Batracobdella species. The transfer of this species to the genus Hemiclepsis is based on the following features exhibited by this leech: dilated head region, three pairs of eyes, central proboscis pore, ten pairs of crop caeca and small genital atria.  相似文献   

14.
The status of Mastodon angustidens pygmaeus Depéret, 1897 is discussed on the basis of an examination of the holotype (a broken lower molar) with tomography using X-rays, and on a review of the previous taxonomic hypotheses. The conclusion is that the holotype is a possible supernumerary post-m3 molar that may be that of a tetralophodont gomphothere. “Mangustidens pygmaeus” is then a nomen dubium that should only be used in relation to the holotype.  相似文献   

15.
Acetes orientalis, a new species of sergestid shrimp belonging to the genus Acetes H. Milne-Edwards collected from the Mandovi estuary, Goa, Central West Coast of India has affinities to most of the Indo-Pacific species. The petasma of the male has resemblance in shape to. A. sibogae, A. vulgaris, A. sibogalis, A. australis, A. erythraeus and Acetes sp. and very much alike in structure to that of A. sibogae. The female genital area has a pair of protuberance as in A. vulgaris and A. indicus. These combinations in characters along with several other important features which justify the creation of this new species are discussed in comparison with those of the other Indo-Pacific species having closet affinities.  相似文献   

16.
The enigmatic, cleptoparasitic bee genera Brachymelecta Linsley and Sinomelecta Baker (Apinae: Melectini) are redescribed, each represented by a single species which has not been reencountered since capture of the type series ca. 1878 and 1900, respectively. Both genera are the only melectines to possess two submarginal cells in the forewing but are otherwise wholly dissimilar. Brachymelecta mucida (Cresson), a species known only from the male holotype collected in “Nevada”, is newly described and figured, including the first account of the hidden sterna and genitalia. Sinomelecta oreina Baker is similarly described and figured based on the holotype male and paratype female, apparently collected from the eastern Tibetan Plateau. Both genera are valid and from the available data do not appear to represent merely autapomorphic forms of Melecta Latreille. Indeed, the terminalia of Sinomelecta oreina are in some respects more similar to those of species of Thyreus Panzer.  相似文献   

17.
The lichenized basidiomycete Lepidostroma vilgalysii from Mexico is described based on morphological analyses. The species is only the second representative of the family Lepidostromataceae documented from the New World, and is one of the few described lichens with an inverted morphology, with the algae in a layer at the base of the thallus. Molecular sequence data from the nuclear ribosomal LSU locus are used to confirm the placement of the holotype in Lepidostroma and to evaluate the molecular distinctiveness of the species from all other described species in the family and genus.  相似文献   

18.
19.
A species of xanthopygine rove beetles is described and figured here as Darwinilus sedarisi gen. n. and sp. n. The holotype was collected by Charles Darwin in Bahía Blanca, Argentina on the Beagle’s voyage. The contributions of Charles Darwin to rove beetle systematics are summarized briefly.  相似文献   

20.
Apristurus platyrhynchus and four related species were reviewed taxonomically.A. sibogae from Indonesia andA. micropterygeus from the South China Sea were valid species.A. verweyi from the Philippines andA. acanutus from the South China Sea were junior synonyms ofA. platyrhynchus. A. platyrhynchus was re-described, and its new biological information was provided.  相似文献   

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