Diversity, distribution and relative abundance of the mosquito fauna (Diptera: Culicidae) of Malakand and Dir Lower, Pakistan

The present study was conducted to evaluate the diversity, distribution (C) and relative abundance (RA) of the mosquito fauna (Diptera: Culicidae) of Malakand and Dir Lower, Pakistan. Collection of specimens (n = 1087) was made during September 2018 to July 2019 at six different habitats including freshwater bodies, rice fields, animal sheds, indoors, drains and sewage waters. Specimens were collected through light traps, pyrethrum spray, aspirators and nets and subsequently killed, preserved and then arranged in entomological boxes for identification. Three genera were identified namely Culex, Anopheles and Aedes. A total of fourteen species were identified namely: Cx. quinquefasciatus (Say, 1823), An. stephensi (Liston, 1901), Cx. tritaeniorhynchus (Giles, 1901), Ae. vittatus (Bigot, 1861), An. maculatus (Theobald, 1901), An. fluviatilis (James, 1902), Cx. vishnui (Theobald, 1901), Ae. aegypti (Linnaeus, 1762) An. subpictus (Grassi, 1899), An. dthali (Patton, 1905), An. culicifascies (Giles, 1901), An. pallidus (Theobald, 1901), Ae. albopictus (Skuse, 1894) and An. annularis (van der Wulp, 1884). Cx. quinquefasciatus was found constantly distributed in the study area with RA = 16.5% and C = 100%. An. annularis was found as a satellite species, sporadically distributed in the study area having RA = 0.9% and C = 17%. Diversity indices of mosquitoes in the studied habitats were found as, Shannon-Wiener Index (2.415), Simpson Index (9.919), Fisher’s Index (2.269) and Margalef’s Index (1.859). A statistically significant difference was recorded in mosquito diversity in the six habitats (Kruskal-Wallis, chi-squared, H = 17.5, df = 5, P = 0.003 at α = 0.05). The present study encompasses mosquito fauna of Malakand, Pakistan with respect to diversity, relative abundance and distribution in diverse habitats and all seasons of the year. This will assist scientists working in various fields related with epidemiology, medical and veterinary entomology, ecology and allied areas of biological sciences.

Community Assembly and Co-occurrence Patterns Underlying the Core and Satellite Bacterial Sub-communities in the Tibetan Lakes

Microbial communities normally comprise a few core species and large numbers of satellite species. These two sub-communities have different ecological and functional roles in natural environments, but knowledge on the assembly processes and co-occurrence patterns of the core and satellite species in Tibetan lakes is still sparse. Here, we investigated the ecological processes and co-occurrence relationships of the core and satellite bacterial sub-communities in the Tibetan lakes via 454 sequencing of 16S rRNA gene. Our studies indicated that the core and satellite bacterial sub-communities have similar dominant phyla (Proteobacteria, Bacteroidetes, and Actinobacteria). But the core sub-communities were less diverse and exhibited a stronger distance-decay relationship than the satellite sub-communities. In addition, topological properties of nodes in the network demonstrated that the core sub-communities had more complex and stable co-occurrence associations and were primarily driven by stochastic processes (58.19%). By contrast, the satellite sub-communities were mainly governed by deterministic processes (62.17%). Overall, this study demonstrated the differences in the core and satellite sub-community assembly and network stability, suggesting the importance of considering species traits to understand the biogeographic distribution of bacterial communities in high-altitude lakes.

Communities of Ditylenchus Destructor Satellite Species of Nematodes in Infected Potato Tubers: Species Composition of Phytonematode Complex and the Structure of their Infracommunities

Within September–April 2016–2017 potato tubers affected by the potato rot nematode Ditylenchus destructor were selected in the potato storage facilities of the Institute of Potato Production of NAAS. 18 species of phytonematodes were identified, including an edificator species of microparasitocenosis and 17 satellite species of this pathogenic phytohelminth, mycohelminths (6 species) and saprobiotic nematodes (11 species). These phytonematodes are representatives of two orders, Rhabditida (11 species from 4 families) and Tylenchida (7 species from 4 families). Nematodes that are part of the group formed by D. destructor and its satellite species are divided into five groups according to quantitative indicators (the prevalence of invasion P and intensity of invasion I). The dominant is one species — D. destructor. Satellite species of D. destructor are divided into four groups, these are subdominants (4 species) and common species (3 species), which together with the dominant species form the core of the group, as well as rare (6) and accidental (4). It was shown that in the course of the disease a regular succession occurs, the species composition of phytonematodes, the grouping structure, the relationship between the number of species of various trophic groups, and the number of certain species change. There are five stages in the course of the disease, from D. destructor colonisation of the tuber, the penetration of the mycohelminths and saprobionts into the focus of the disease, and the disappearance of D. destructor. The maximum number of D. destructor occurs at stage III, mycohelminths — at stage IV, and saprobiotic nematodes — at stage V. Infracommunities consist of from two to seven species. The distribution of all the studied tubers by the number of species in the infracommunity is close to normal, most often 3–4 species of nematodes were found, several species of nematodes of the same genus are extremely rare in a particular infracommunity.

Of Viroids and Prions

In 2017, Hadidi et al. edited a voluminous monograph entitled “Viroids and Satellites”, in which each known viroid and viroid-like satellite species was described in detail from many perspectives by more than 100 experts from 24 countries. In its 700+ pages, the book is a much needed detailed and reliable compendium of a subject, which, undoubtedly, is still little known by many potential readers. Because most users of the book may be expected to be practical plant pathologists, it appears essential that the book contain, in addition to the detailed viroid and satellite descriptions, one chapter, in which the basic molecular biology of viroids and satellites is described.

Composition and structure of the helminth community of Columba livia (Gmelin, 1798) (Aves, Columbidae), in the municipality of Juiz de Fora, Minas Gerais state, Brazil

The objective of the present study was to describe the composition and structure of the helminth community present in domestic pigeons, in the municipality of Juiz de Fora, Minas Gerais, Brazil. The helminthological survey of 35 hosts revealed the presence of two digenetic trematodes, Tanaisia (Paratanaisia) bragai (prevalence 51.42%, mean intensity 288.8 ± 403.86 and mean abundance 148 ± 320.9) and T. inopina (prevalence 2.85% and mean abundance 0.68 ± 4.05); five cestodes, Raillietina allomyodes (prevalence 34.28%, mean intensity 6.66 ± 9.14 and mean abundance 2.28 ± 6.11), Raillietina sp. (prevalence 37.14%, mean intensity 9 ± 10.68 and mean abundance 3.34 ± 7.7), Skrjabinia bonini (prevalence 20%, mean intensity 2.14 ± 1.21 and mean abundance 0.42 ± 1), Skrjabinia sp.( prevalence 5.7%, mean intensity 6 ± 7 and mean abundance 0.34 ± 7) and Fuhrmanneta sp. (prevalence 2.85% and mean abundance 0.028 ± 0.16) and four nematodes, Baruscapillaria obsignata (prevalence 51.42%, mean intensity 29.72 ± 44.2 and mean abundance 15.28 ± 34.7); Ascaridia columbae (prevalence 51.42%, mean intensity 60.55 ± 79.88 and mean abundance 31.14 ± 64.2); Tetrameres fissipina (prevalence 14.28%, mean intensity 346.3 ± 504.4 and mean abundance 49.42 ± 212.1) and Synhimanthus (Dyspharynx) nasuta (prevalence 2.85% and mean abundance 0.028 ± 0.16). Among the examined hosts, 97.2 % were found parasitized by at least one helminth species. In accordance with the prevalence of each species T. bragai, A. columbae and B. obsignata were considered secondary species and T. inopina, T. fissipina, S. nasuta, S. bonini, Skrjabinia sp., R. allomyodes, Raillietina sp. and Fuhrmanneta sp. were considered satellite species. All the species exhibited aggregate distributions, which is the most common distribution pattern in helminth populations.

Abundance and distribution of endoparasitic helminths in Anabas testudineus (Bloch, 1792) from a polluted beel of Bangladesh

Abundance and distribution of the endoparasitic helminths in Anabas testudineus (collected from a polluted water body) was analyzed. Out of 50 fish observed, 42 (84%) were parasitized by at least one species. Five metazoan endoparasites, one trematode (Neopecoelina saharanpuriensis) and four nematodes (Ascaridida sp., Contracaecum sp., Camallanus anabantis and C. pearsei) were recorded. Prevalence was higher in female (90%) hosts than males (75%). A significant positive correlation was observed between the standard length of the host and the abundance for parasites except Ascaridida sp. Nematodes were the more prevalent group (72%) than trematodes (48%). No parasitic species was observed as central species category; three parasites (N. saharanpuriensis, Ascaridida sp. and Contracaecum sp.) were considered as secondary and Camallanus spp. as satellite species. All nematode parasites showed aggregated distribution pattern and the trematode showed random distribution pattern. Interspecies association between two species of parasite was low.Bangladesh J. Zool. 42(1): 1-10, 2014

The occurrence of acanthocephalans in teleost fish from the Bizerte lagoon, Tunisia

Seven species of acanthocephalans were identified for the first time in teleost fish from the Bizerte lagoon, Tunisia, including Neoechinorhynchus (Hebesoma) agilis (Rudolphi, 1819) Van Cleave, 1916; N. (Neoechinorhynchus) rutili Müller, 1780 (Neoechinorhynchidae); Acanthocephaloide propinquus (Dujardin, 1845) Meyer, 1932; A. incrassatus (Molin, 1858) Meyer, 1932 (Arhythmacanthidae); Longicollum pagrosomi Yamaguti, 1935 (Pomphorhynchidae); Rhadinorhynchus cadenati (Golvan et Houin, 1964) Golvan, 1969 (Rhadinorhynchidae); and Telosentis exiguus (von Linstow, 1901) Van Cleave, 1923 (Illiosentidae). Acanthocephaloide propinquus, N. (N.) rutili, L. pagrosomi and R. cadenati were restricted to the rectum and the posterior intestine, whereas the other species (A. incrassatus, T. exiguus and N. (H.) agilis) colonized two or three parts of the intestine. The most diverse acanthocephalan fauna was recorded in Lithognathus mormyrus, with three species; two species were reported from Trachurus trachurus; and a single species was recorded in Liza aurata and in Atherina boyeri. Neoechinorhynchus (N.) rutili, L. pagrosomi and R. cadenati attained the lowest prevalences of less than 6% and were considered as to be rare species. Acanthocephaloide incrassatus, A. propinquus, T. exiguus and N. (H.) agilis were satellite species. The diversity of the acanthocephalan fauna in the fish from the Bizerte lagoon is compared with previous studies from other localities. The report of A. incrassatus, A. propinquus and N. (N.) rutili in L. mormyrus presents new host records in Mediterranean waters.

Community structure analysis of endoparasitic helminths of Anabas testudineus (Bloch, 1792) from a fresh water body of Bangladesh

Community structure of the parasites of Anabas testudineus was analyzed collected from a fresh water body, Turag River at Diabari, Mirpur point of Dhaka, Bangladesh. Out of 50 A. testudineus fish observed, 36 (72%) were parasitized by at least one species of helminth endoparasites. Six metazoan endoparasites were recorded: two trematodes (Allocreadium minutum, Neopecoelina saharanpuriensis) and four nematodes (Ascaridida sp., Gnathostoma spinigerum, Contracaecum sp., Paragendria wallagonia). Prevalence was higher in female (81.25%) hosts than male (55.56%). Nematode was more prevalent group (70%) than trematode (62%). All parasite species were accounted as secondary species category; no central or satellite species accounted in the sample. A significant positive correlation was observed between the standard length of the host with the prevalence and abundance of all parasites in this sample fishes. Two parasites (A. minutum and Ascaridida sp.) showed typical over-dispersed distribution pattern and other four parasites (N. saharanpuriensis, G. spinigerum, Contracaecum sp. and P. wallagonia) showed random distribution pattern. Interspecies association between two species of parasite was moderately strong. The host’s sex did not affect the parasite diversity and abundance.J. Asiat. Soc. Bangladesh, Sci. 40(1): 67-77, June 2014