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1.
Crystal Ball Cave is located in a small outlier of the Snake Range in Snake Valley 1.7 km (1 mile) west of Lake Bonneville at its highest level. Original vertebrate skeletal material (mostly mammalian) has been found in shallow dry dust 61 m (200 feet) inside the cave. Radiocarbon dates show that fossils have been accumulating since at least 23,000 Y.B.P. It appears that wood rats and possibly small carnivores transported the fossils into the cave because only the smallest elements of large mammals are represented. The fossil assemblage represents a much more boreal community than the present local fauna. Fish, Ondatra zibethicus , and Mustela cf. vison , which require perennial water, were recovered, as were Ochotona princeps , Lepus cf. Americana , Microtus cf. pennsylvanicus , Vulpes vulpes , and Martes americana , which have also been extirpated from the Snake Range. Marmota flaviventris , Neotoma cinerea , cf. Cervus elaphus , and Ovis Canadensis were recovered but now occur only at higher elevations in the range. Extinct taxa recovered are Smilodon cf. fatalis , Equus species, Camelops cf. hesternus , Hemiauchenia cf. macrocephala , cf. Symbos cavifrons , and a new species of Brachyprotoma , herein named B. brevimala . This is the first recovery of Brachyprotoma from the western United States.   相似文献   

2.
Polydora websteri belongs to a group of the Spionidae known as the Polydora complex, members of which are known for building tubes within the shells of mussels and for their ability to infest commercially valuable bivalves, which causes serious losses for malacoculture. P. websteri is a species subjected to increasing research due to the global scale at which these infestations occur. In this paper, we describe the larval development of P.cf. websteri associated with the oyster Crassostrea cf. brasiliana in a tropical region of north-east Brazil. The main structures of all stages of development were analysed and compared to other populations of P. websteri. Ovigerous capsules of P.cf. websteri were cultured in the laboratory and the larval stages were analysed until metamorphosis. Ovigerous capsules were present in all sampling intervals, indicating that this population exhibits continuous reproduction. Up to 21 capsules per tube were found, and the number of eggs per capsule varied from 20 to 40. All observed eggs developed into larvae. Larval development from egg to recruitment stage did not exceed 13 days. Metamorphosis occurred when larvae attained 17 chaetigers, at which stage important diagnostic characteristics were revealed, such as the spines on chaetiger 5. The developmental stages of P.cf. websteri larvae, and the morphological features found at each stage, are in accordance with what has been recorded for temperate populations. In our study, the planktonic stage was found to be of shorter duration than elsewhere, which might be associated with the higher temperatures at which larvae were cultured compared to previous studies.  相似文献   

3.
Belgrandiella A. J. Wagner, 1927 is a genus comprising minute snails with conic or turriform shells that are facultative stygobionts, inhabiting subterranean waters and springs. Few specimens or even empty shells of this taxon can be found, so the taxonomy is based mostly on the shell morphology and geographic distribution. Anatomy is known for a few taxa, and its usefulness is restricted. This, coupled with a popular idea that isolation is the first factor shaping divergence and speciation of the spring/cave fauna, resulted in dozens of nominal species of Belgrandiella, known from shells at a given locality. Herein we present shells, anatomy and four molecular markers (nuclear H3, 18S and 28S and mitochondrial cytochrome oxidase subunit I) in Belgrandiella from 16 localities in Slovenia, northern Croatia, and Bosnia and Herzegovina. Five sites are type localities of Boleana umbilicata, Belgrandiella kusceri, Belgrandiella krupensis, Belgrandiella zermanica and Belgrandiella robusta, respectively. Considering the shell and geographic distribution, we have determined B. cf. robusta Belgrandiella cf. croatica, Belgrandiella cf. fontinalis, Belgrandiella cf. kuesteri, Belgrandiella cf. pageti and Belgrandiella cf. koprivnensis The shells of all, as well as penes and female reproductive organs of two putative, species have been illustrated. Molecular analysis indicates four distinct clades, most probably of species rank for B. kusceri, B. cf. kuesteri, B. cf. fontinalis and B. cf. koprivnensis. Four nominal species (B. krupensis, B. robusta, B. umbilicata and B. zermanica) and one genus (Boleana) must be synonymised with Belgrandiella kusceri, and there are no more than four valid, biological species in the studied Belgrandiella. The molecular divergence is completely unmirrored by high morphological variability. Hence the level of endemism is markedly overestimated in these snails.  相似文献   

4.
《Journal of Natural History》2012,46(13):1711-1722
Physalaemus cf. fuscomaculatus is a foam-nesting frog of seasonally dry environments of south-eastern Brazil. We report on the reproduction and other natural history features of this species. Population parameters were based on trapped specimens. The advertisement call is described. The calling and spawning season is coincident with the rainy period. Calling and spawning were performed in ponds. Most of the adults were trapped in October and the juveniles during wetter months and the beginning of the dry season. At the end of the reproductive season, the median size of adults lowered. Egg clutches averaged 2350 eggs, each egg being about 1.4?mm in diameter. Males were more abundant than females in traps. Communal foam nests were frequent, involving up to 40 individual nests. Tadpoles entered the water within about 40?h. Maggots (Diptera) infested egg clutches; water bugs and mammals preyed upon adults. In this region, the dry/cold season may be so difficult for survival that early maturation at small size would be advantageous. The male-biased sample may be related to the greater motility of males. The rapid abandonment of the foam by the tadpoles and communal nesting may help to reduce predation by maggots. Skin toxins were not effective in deterring predation upon adults. The call of P. cf. fuscomaculatus differs from that of other species in the biligonigerus group and can help to define the specific status of the studied population.  相似文献   

5.
The structure and composition of the test wall in seven species of Bathysiphon, a genus of large, tubular agglutinated foraminifers (Astrorhizacacea), have been studied using high-resolution SEM. In all cases the wall is composed mainly of quartz grains and varying proportions of sponge spicules which, in some species, show a characteristic orientation within the wall. Three species, B. capillare, B. flavidus and B. rufus, have a well-defined, but very thin (1 μm) outer layer consisting of flat-lying or imbricated plate-like mineral grains. Bathysiphon stictus has a less well-defined surface veneer of tiny mineral grains while in B. major the surface layer is composed of dark-grey or dark-brown particles of an indeterminate nature. The test fabric is rather open and, in all species, the intergranular spaces are partly occupied by an organic cement which forms either a meshwork of fine, branching and anastomozing fibres or shorter, column-like strands. All species also have an inner organic test lining. Thus, the basic structure and composition of the test wall is fairly uniform, but some features show interspecific variability. Some incidental observations on the organization of the protoplasmic body are also reported.  相似文献   

6.
Five new species of bariliin cyprinid fishes are described from West Africa. Three belong to the genus Leptocypris and two to Raiamas. One species of each genus is from Guinea (Konkoure river) and from Sierra Leone (Taia and Little Scarcies rivers), the other, a Leptocypris, is from Cameroon (Cross River). A taxon of indeterminate generic identity from Guinea is also described. The phylogenetic relationships of the bariliins are hypothesized and in this light their geographical distribution is compared with that of other cladistically analysed African freshwater fish groups. The significance to West African fish distribution of the Togo-Benin (Dahomey) Gap is discussed.  相似文献   

7.
Phylogenetic relationships of the Aegean Helix cincta and Helix nucula with congeneric species found in Greece were inferred using mitochondrial DNA sequence data. Twenty-three specimens from mainland Greece, Aegean Islands, Cyprus and North Africa were analysed, revealing that (1) H. nucula is monophyletic, (2) H. cincta from Greece and Cyprus is paraphyletic, and so questions arise regarding the taxonomy of this species, and (3) H. cf. cincta from Tunisia might be considered as a distinct evolutionary lineage. Moreover Helix valentini, an endemic species of Kalymnos Island group, is clustered within the lineage of H. c. anatolica, so supporting the synonymy of the two ‘species’, and the elevation of H. c. anatolica to species level. Hence, our results stress the need for a taxonomic reconsideration of H. cincta in the Aegean Sea, indicating that sequence data can prove useful in overcoming taxonomic issues at both species and subspecies level.  相似文献   

8.
ABSTRACT

Two species of bopyrid isopods of the Bopyrinae subfamily are recorded from new localities and hosts in northeastern Brazil. Parabopyrella lata (Nierstrasz and Brender à Brandis, 1929) was recorded from the state of Ceará, found for the first time parasitising the caridean shrimp Alpheus packardii Kingsley, 1880. In addition, Probopyrus cf. pandalicola (Packard, 1879) is recorded from the state of Bahia, parasitising the palaemonid shrimp Palaemon northropi (Rankin, 1898). Taxonomic comments are provided for each species.  相似文献   

9.
《Journal of Natural History》2012,46(16):1887-1986
Fifty-one species are recognized in the genus Paurocephala, with an additional 14 species which remain unnamed. Thirty-five species are described as new, and five species are synonymized: P. pumilae and P. zhejiangensis with P. chonchaiensis, P. debregeasiae with P. sauteri, and P. guangxiensis and P. tremae with P. trematos. Two varieties, P. psylloptera maculipennis and P. psylloptera setifera, are raised to species level. P. bifasciata is reinstated from former synonymy with P. chonchaiensis, and Anomoterga kleinhofiae is transferred back to Paurocephala. Lectotypes are designated for P. brevicephala, P. chonchaiensis, P. psylloptera, P. sauteri, P. setifera and P. wilderi. The four New World species of Paurocephala are not considered to be congeneric with the Old World species and will be transferred to Diclidophlebia. Two South African species, P. bicarinata and P. hottentotti, are removed from Paurocephala and have to be accommodated in a new genus in the Diaphorininae. Thus Paurocephala is an Old World genus with nine Afrotropical and 42 Indo-Australian described species. Keys for the identification of adults and fifth instar larvae are provided. All 51 named species are diagnosed and illustrated, and information is given on distribution and host plants. Based on two cladistic analyses, one using adult characters only, and one using both adult and larval characters, four monophyletic species groups are recognized. In both analyses a basal group of 10 species, the brevicephala -group, forms the sister group to all other Paurocephala spp. The Afrotropical species are monophyletic and, together with one Oriental species constitute the gossypii group. In the analysis with adult characters only, the gossypii -group is the sister taxon of the kleinhofiae -group and, both together, are the sister group of the psylloptera -group, the largest species group with 27 species. In the analysis of adult and larval characters, the relationships between the last three species groups are not resolved. The result of the phylogenetic analysis confirms the synonymy of the subgenus Thoracocorna with Paurocephala. Known host plants of Paurocephala spp. belong to the Malviflorae with the exception of the Afrotropical P. insolita which develops on Theiflorae (Theales, Clusiaceae). The brevicephala -, kleinhofiae - and gossypii -groups are associated with hosts of the order Malvales (Malvaceae and Sterculiaceae), whereas the psylloptera -group is with Urticales (Urticaceae, Moraceae and Ulmaceae).  相似文献   

10.
《Journal of Natural History》2012,46(15):1969-1997
Sympatric reed frog species were studied in Gabon (Monts Cristal: Hyperolius mosaicus, H. pardalis, H. tuberculatus) and Kenya (Kakamega Forest: Hyperolius acuticeps, H. cf. cinnamomeoventris, H. kivuensis, H. lateralis, H. viridiflavus). For each taxon, a standardized diagnosis covering 11 aspects of adult and in part tadpole morphology as well as the sequence of a 560 bp fragment of mitochondrial DNA of the 16S ribosomal gene are provided. In addition, behavioural data are given for each species including measurable parameters of advertisement calls. The Monts Cristal Hyperolius species clearly differ in their spatial arrangement through the choice of breeding site. Hyperolius species at the Kakamega Forest share the same breeding sites but in part differ in their activity pattern throughout the year. Advertisement calls of sympatric species in both regions mainly differ in temporal parameters.  相似文献   

11.
Members of the algal class Phaeophyceae (brown algae) are almost entirely marine species. A few genera have been described from freshwater habitats, but their distribution and ecological requirements, especially in North America, are very poorly known. The 1st specimens of a freshwater species of brown algae from Oregon, Heribaudiella fluviatilis , were discovered in 3 localities of the McKenzie River, near McKenzie Bridge and Belknap Springs (44°22′N, 122°00′-15′W). This is the 4th extant population of this species known from the United States. The alga forms distinctive, macroscopic, dark brown patches on rocks in rapidly flowing water. In the McKenzie River it co-occurs, apparently year-round, with several other macrophytic algal species, including Prasiola Mexicana , Zygnema sp. (sterile), Nostoc parmelioides , N. vemlcossum , and Phormidium cf. autumnale . In cooler months the macroalgal species Ulothrix zonata and Hydrurus foetidus are also present with Heribaudiella . Photographs and ecological information are provided. We report a 380-km range extension south for the species, and thus far the most southerly population known from North America. This new record suggests that the alga may be more widespread than previously recognized and that other localities may be discovered with further study.  相似文献   

12.
13.
《Journal of Natural History》2012,46(6):1131-1161
This paper deals with a study of demosponge fauna inhabiting the red coral facies on the circalitoral bottoms surrounding the Alboran Island (Western Mediterranean, Alboran Sea). A total of 58 species were recognized, after examining a total of 107 sponges. Two of these species are new to science (Plakinastrella mixta sp. nov. and Leptolabis megachela sp. nov.) and another one (Rhaphidectyon spinosum Topsent) is recorded for the first time in the Mediterranean. Some other specimens collected belonging to poorly known species, such as Erylus papulifer Pulitzer-Finali, Isops anceps (Vosmaer), Spongosorites flavens Pulitzer-Finali and Timea cumana Pulitzer-Finali, are described briefly. Two controversial specimens, assigned to Microciona spinarcus and Plocamilla cf. novizelanica, are also described and discussed. A high degree of epibiosis and abundance of rare species were the major features characterizing the material studied.  相似文献   

14.
《Journal of Natural History》2012,46(47):4031-4065
The first records on the genus Platypalpus Macquart from Thailand are presented including 10 species new to science: P. fai sp. nov., P. gaemluang sp. nov., P. hualuang sp. nov., P. isaanensis sp. nov., P. nuadkhao sp. nov., P. phomyaaw sp. nov., P. seedam sp. nov., P. seeluang sp. nov., P. siamensis sp. nov., and P. thaicus sp. nov.. A key to these species is provided. All species of Platypalpus known from the Oriental Region (totally 54) are arranged into the species groups currently established for the genus. Eight species groups are recognized from the Oriental Realm and the distribution of each group is briefly discussed. The P. albiseta‐group is most diverse in the Orient with 16 species recorded. Two species of this group possess a modified structure and vestiture of certain abdominal segments that is the first record of this phenomenon in Platypalpus. Also, within the P. albiseta‐group a complex of closely related species sharing an apomorphous condition of the hypoproct has been recognized. In these species the structure of the hypoproct is likely to deal with clasping during copulation instead of the cerci and epandrial lamellae.  相似文献   

15.
Twenty‐six marine benthic ciliates including seven new species were isolated from King George Island, Antarctic. The morphology and taxonomy of 19 of them are described in the present paper: Aegyriana paroliva, Amphileptus sp., Amphisiella antarctica nov. spec., Condylostoma cf. magnum, Dysteria parovalis nov. spec., Folliculina ? sp., Hartmannula cf. angustipilosa, Hemigastrostyla szaboi nov. spec., Heterostentor coeruleus, Holosticha sp., Intranstylum antarcticum nov. spec., Metaurostylopsis rubra, Orthodonella shenae, Philasterides cf. armatalis, Pithites pelagicus nov. spec., Pleuronema coronatum, Strombidium apolatum nov. spec., Telotrochidium sp., and Thigmokeronopsis magna nov. spec. Based on the new observations, an improved diagnosis for the genus Aegyriana is suggested: dorsoventrally flattened Dysteriidae with tail‐shaped podite, which is positioned subcaudally in a glabrous region within somatic kineties; oral structure in two parts: ca three close‐set fragments on right and one preoral kinety on left; left postoral kineties shortened posteriorly and continuous with right ones, leaving no median gap or suture; cytopharyngeal rods dominant. According to the new understanding and information obtained, a refined diagnosis of the genus Hemigastrostyla is also suggested: hypotrich with Oxytricha‐like cirral pattern; eight to ten frontal (including one buccal) and five to seven ventral cirri; five transverse and three caudal cirri; no right‐lateral anlagen of dorsal kineties occurring and the old adoral zone will be partly replaced by newly formed structure during morphogenesis; dorsal cilia located in small pits, fibre system highly developed; marine habitat.  相似文献   

16.
17.
Three new aorid amphipod species from Tasmanian kelp holdfasts are described: Microdeutopus varietensis sp. nov., Lembos clematis sp. nov. and L. verrucularum sp. nov. Strong sub-ocular regression of the head is a usual feature of the genus Microdeutopus and is shown by M. varietensis. It is not, however, typical of the other known Australian/NewZealand Microdeutopus species (M. haswelli and M. apopo). The Tasmanian Lembos species (L. chiltoni, L. clematis and L. verrucularum) are not known from New Zealand, where the genus is represented by L. pertinax, L. acherontis and L. hippocrenes. The Tasmanian Lembos species display the condition of the mandibular palp that typifies the genus, that is, article 3 longer than article 2 (cf. the New Zealand species which display the reverse, unusual, condition).  相似文献   

18.
《Journal of Natural History》2012,46(5):1077-1173
The Cassidininae of Australia are revised. The status of the subfamily is assessed and it is concluded that, as presently constituted, the Cassidininae is an artificial taxon. It is maintained here as a taxon of convenience (sensu lato) until the other sphaeromatid subfamilies can be reassessed, but a new diagnosis (sensu stricto) is given. The genus Cassidina is redescribed. Three new genera are established: Agostodina gen. nov. (type species: A. munta sp. nov.), Apemosphaera gen. nov. (type species: A. naranagi sp. nov.) and Discidina gen. nov. (type species: D. banawarra sp. nov.). New diagnoses are provided for the genera Cassidina Milne Edwards, Chitonopsis Whitelegge, Cassidinidea Hansen, Paracassidina Baker, Syncassidina Baker and Platysphaera Holdich and Harrison. The genus Dies is placed in synonymy with Cassidinidea and an annotated list is given of all species of the genus. The following new species (excluding the new type species) are described: Chitonopsis booyoolie, Agostodina munta, Paracassidina anasilla, P. bakeri, P. bamarook, P. bilbie, P. cervina, P. dama, P. fuscina, P. incompta, P. kutyo, P. munna, P. petala, P. prolata, P. wurrook and Cassidinidea korpie. Keys to the Australian genera and species are given.  相似文献   

19.
Three hosts from Indo-west Pacific including Kiribati, Guam Island and Australia were examined, and found to be infested by three species of the subfamily Argeiinae. We describe Paraeragia kiribatiensis gen. nov., sp. nov. from Kiribati infesting Synalpheus gracilirostris. The new genus is most related to Eragia and it can be distinguished by female with triangular pleon, lateral plates extend posteriorly, paired uropods, widely opened brood pouch. Argeiopsis guamensis sp. nov. from Guam Island infesting Synalpheus cf. stimpsoni. The new species is most similar to Argeiopsis inhacae but differs in female with curved posterior margin of first oostegite, partly fused pleomeres, and male with head separated from first pereomere, pleon as wide as seventh pereomere. We also record Stegoalpheon kempi from Australia for the first time, infesting Alpheus cf. perplexus. Keys to the nine genera of Argeiinae, and to three species of Argeiopsis are provided. A table for all 13 species of Argeiinae with localities and host records is also provided. A table comparing the distribution of lateral plates and morphology of pleopods and uropods among argeiine genera is presented.

http://www.zoobank/urn:lsid:zoobank.org:pub:284AB32C-6AE5-45BC-9C5D-01B3030D6DE6  相似文献   


20.
We addressed the following question: Do conifers within aspen stands (conifer invasion) increase bird species diversity in western landscapes? We tested the hypotheses that bird species diversity, measured as species richness or with the Shannon-Weiner diversity index, responds to aspen-conifer ratios (from 0% to 100% conifer) in a quadratic manner with a maximum occurring at an intermediate ratio of aspen and conifer. Extra sum-of-squares F tests comparing quadratic with linear models suggested that migratory bird diversity was inversely linearly related to the extent of conifer invasion. These linear responses were moderate (species richness: R 2 ≥ 0.34, P 2 ≥ 0.34, P 2 ≤ 0.13, P ≥ 0.09) and was marginal for the Shannon- Weiner diversity index (R 2 ≤ 0.27, P ≤ 0.01). We concluded that mixed aspen-conifer stands do not have higher bird species diversity than pure aspen stands and that management activities should focus on heavily conifer-invaded stands to increase bird diversity in western landscapes and help reverse the decline of aspen habitat due to conifer invasion.  相似文献   

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