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1.
ABSTRACT

In South America, Megalobulimus includes a number of threatened species, as well the largest land snails on the continent. The activity patterns and reproductive aspects of this group have not been documented. This work describes the daily and seasonal activity patterns and reproduction of M. paranaguensis. We maintained specimens in the laboratory for one year, and we quantified their behaviour for one hour at four different times of the day (0 h, 6 h, 12 h and 18 h) during three days in four months (August, September, April and May). The number of postures, hatching rate, time of hatching since oviposition and mortality rate among juveniles for each month were also quantified. Megalobulimus paranaguensis was more active in August, and had a egg laying peak one month after. Fifty-one eggs were laid by 12 captive individuals throughout the year, with a mean value of 4.25 eggs per individual. The hatching rate was 80.39%, and the time of hatching since oviposition was 56.7 ± 4.3 days. In two eggs, we observed the presence of twins. The mortality rate among juveniles was low (9.30%) indicating that rearing land snails in captivity has the potential to be an important and viable tool for the management and conservation of these organisms.  相似文献   
2.
The role of breeding birds as indicators of sustainable management in olive groves was investigated. The data revealed significantly higher alpha diversity in organic and abandoned olive groves and maquis than in conventional ones. The highest beta diversity was found between the following pairs: organic olive groves–maquis, and abandoned olive groves–maquis. Breeding bird diversity, Heteroptera, Hymenoptera, Hemiptera and Coleoptera densities positively influenced bird species richness in organic olive groves and maquis, and additionally, manure application positively influenced bird species richness in organic ones. Bird species richness was negatively influenced by pesticide and inorganic fertilizer application in conventional ones. Moreover, isopod density was unimportant in explaining breeding bird richness in organic olive groves. Finally, our study suggests a difference in bird communities of various olive groves as a result of different management and practices, and concludes that birds might serve as indicators of overall olive grove health. Furthermore, these findings could be used as a tool for prediction of breeding bird species richness probability in different olive grove management systems and maquis. Finally, the results of the present study may contribute to highlighting some aspects of the effect of different farming practices on the dynamics of Mediterranean bird communities.  相似文献   
3.
Parasites of the grey mullet Mugil cephalus collected from Lower K?z?l?rmak Delta in Turkey were investigated. Trichodina puytoraci, Trichodina lepsii, Ligophorus mediterraneus, Ligophorus cephali, Gyrodactylus sp., Microcotyle mugilis, Ascocotyle (Phagicola) longa, Haplosplanchnus pachysomus, Diplostomum spathaceum, Tylodelphys clavata, Posthodiplostomum sp., Neoechinorhyncus agilis and Ergasilus lizae were identified. Overall infection prevalence (%), mean intensity and mean abundance values were 99.61%, 458.10 ± 75.72 and 456.30 ± 75.44, respectively. Infection indices of parasite species in relation to season, lakes/lagoons and some physicochemical parameters of water such as temperature, salinity, dissolved oxygen and nitrate are determined and discussed. Posthodiplostomum sp. is a new parasite record for mugilids and Diplostomum spathaceum is the first record in M. cephalus, in the present study. Moreover, Ligophorus mediterraneus, Ligophorus cephali and Ergasilus lizae are new records for Turkish parasite fauna of fish and Mugil cephalus is a new host record for Neoechinorhyncus agilis in Turkey.  相似文献   
4.
《Journal of Natural History》2012,46(8):1289-1302
Most soil fauna in tropical rainforests require a pre-existing shelter for at least part of their life cycles. Among termites and ants, the most frequently encountered taxa, the availability of appropriate nesting sites is a major factor controlling the multiplication of colonies. Work carried out in five forests in southern Cameroon indicates that termitaries of Cubitermes subarquatus, whether active or abandoned, provide shelter for large numbers of invasive invertebrates, particularly ants and other termite species, and may be a determining factor in the patchy distribution of many taxa. Dissections of 90 termitaries (65 active, 25 abandoned) produced a great diversity of invasive fauna, including 354 ant colonies representing 75 species in 31 genera. Ants occurred in all abandoned termitaries but 6·1% of active termitaries had no ants present. Nevertheless, in total active termitaries sheltered more ant colonies (273) than did abandoned ones (81). Every termitary examined also sheltered founding pairs or incipient colonies of alien termites, but active C. subarquatus termitaries yielded fewer mature colonies of alien termites (56·9%) than did abandoned ones (84%).  相似文献   
5.
A new genus and species of the family Parabathynellidae, Sabahbathynella wongi, is described. It has been discovered in the interstitial of coarse sand filling the spaces between big stones of the bank along a stream in Sabah on Borneo. The new genus of the family Parabathynellidae exhibits some unusual features which make it impossible to assess its phylogenetic position. There are some convergencies with the genus Thermobathynella.  相似文献   
6.
《Journal of Natural History》2012,46(5):1177-1193
Seventeen species of Psocoptera are recorded from Bermuda, increasing the known number from three. Four new species are described: Echmepteryx atlantica n. sp., Caecilius bermudensis n. sp., Indiopsocus hilburni n. sp., and I. nebulosus n. sp. The latter two species appear to be closely related and two alternative hypotheses are proposed for their origin. Ectopsocus spilotus Thornton and Wong is recorded outside the central Pacific area for the first time. The species are assigned to four categories according to probable duration of time on Bermuda and probable source of original invaders: (1) endemics (four species); (2) species with wide distributions in the tropics and subtropics, not restricted to islands and sea coasts (four species); (3) species largely restricted to sea coasts and islands, not necessarily tropical (three species); (4) species widely distributed in southeastern United States, not restricted to the sea coast or the subtropical region (five species).  相似文献   
7.
《Journal of Natural History》2012,46(5-6):309-321
Montanabathynella salish gen. nov. sp. nov., of the family Parabathynellidae, from Montana, USA, is described. The new species displays several exclusive characters: distal endite of the maxillule with nine claws and a very large and distinctive male thoracopod 8 with four lobes in the basal penial region and a long recurved exopod without setation. It also presents a unique combination of characters: antennule seven‐segmented; antenna six‐segmented; labrum with 18 teeth; exopod of thoracopods three‐ to six‐segmented, endopod with one dorsal seta on the first and second segments and epipod only present on thoracopods 4 to 7; pleopods absent; endopod of thoracopod 8 male with two setae and exopod without setae; female thoracopod 8 having two segments, first segment with two groups of denticles and the second one with three long barbed setae; 15 spines on sympod, four spines and spinous process on endopod and 12 setae on exopod of uropod.  相似文献   
8.
9.
《Journal of Natural History》2012,46(17):1407-1429
Four new freshwater gobies of the genus Rhinogobius Gill, were collected from the river running into the Gulf of Tonkin in northern Vietnam. They are Rhinogobius boa new species, Rhinogobius variolatus new species, Rhinogobius virgigena new species and Rhinogobius sulcatus new species. These four new species can be distinguished from other congeneric species by a combination of characters such as the meristic features, shape of body, shape of first dorsal fin and coloration pattern.  相似文献   
10.
《Journal of Natural History》2012,46(21-22):1549-1563
That the ties between any obligate subterranean species and the hypogean environment depend on the interplay of a species' own physiological characteristics and all of the ecological characteristics of the adjacent epigean habitat(s), including biotic factors, has been emphasized. The reasons why troglomorphy cannot be included within criteria for classifying cave dwellers have been demonstrated. After a review of historic classifications, standardized definitions of the most widely used terms are proposed. The most easily recognized are four categories which are terminological approximations of the classic Schiner‐Racovitza terminology: (1) troglobiont is a species or population, strictly bound to a hypogean habitat; (2) eutroglophile is an essentially epigean species, but able to maintain a permanent subterranean population; (3) subtroglophile is inclined perpetually or temporarily to inhabit a subterranean habitat but is bound to the surface for some biological functions (e.g. feeding); (4) trogloxene is a species only occurring sporadically underground.  相似文献   
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