MyMedR

Displaying publications 21 - 30 of 30 in total

Abstract:

Sort:

Morphology of immature stages of Megaselia spiracularis Schmitz (Diptera: Phoridae)

Dian-Xing F, Guang-Chun L

Microsc Res Tech, 2012 Sep;75(9):1297-303.
PMID: 22522698 DOI: 10.1002/jemt.22064

In addition to causing myiasis in humans, Megaselia spiracularis Schmitz has also been reported as a forensically important fly. In this study, we presented the morphology of all larval instars and puparium of M. spiracularis using scanning electron microscopy. The first instar larva was composed of 12 segments. Antennae and maxillary palp complex were visible. Two spiracular slits could be seen at the posterior spiracle. The branch of posterior spiracular hairs was approximately equal to the palm-formed base in length. Second and third larval instars were very similar to first instar, except for the presence of anterior spiracle. The labium of the second instar larva was triangular and ventrally curved, whereas it was a bilobed structure and the tip forked in the first instar. The bubble membrance comprised of ≈40 globules presented at the third instar larvae. Puparia showed a retracted cephalic region and a pair of pupal respiratory horns on the dorsum. A comparison of the morphological features between immature stages of M. spiracularis and M. scalaris, a forensically important fly indoors in Germany, Malaysia, and China, was discussed.

Matched MeSH terms: Pupa/growth & development
Fulltext Bacterial Larvicide, Bacillus thuringiensis israelensis Strain AM 65-52 Water Dispersible Granule Formulation Impacts Both Dengue Vector, Aedes aegypti (L.) Population Density and Disease Transmission in Cambodia

Setha T, Chantha N, Benjamin S, Socheat D

PLoS Negl Trop Dis, 2016 09;10(9):e0004973.
PMID: 27627758 DOI: 10.1371/journal.pntd.0004973

A multi-phased study was conducted in Cambodia from 2005-2011 to measure the impact of larviciding with the bacterial larvicide, Bacillus thuringiensis israelensis (Bti), a water dispersible granule (WG) formulation on the vector, Aedes aegypti (L.) and the epidemiology. In our studies, all in-use containers were treated at 8 g/1000 L, including smaller containers and animal feeders which were found to contribute 23% of Ae aegypti pupae. The treated waters were subjected to routine water exchange activities. Pupal production was suppressed by an average 91% for 8 weeks. Pupal numbers continued to remain significantly lower than the untreated commune (UTC) for 13 weeks post treatment in the peak dengue vector season (p<0.05). Suppression of pupal production was supported by very low adult numbers in the treated commune. An average 70% of the household harbored 0-5 Ae aegypti mosquitoes per home for 8 weeks post treatment, but in the same period of time >50% of the household in the UTC harbored ≥11 mosquitoes per home. The adult population continued to remain at significantly much lower numbers in the Bti treated commune than in the UTC for 10-12 weeks post treatment (p<0.05). In 2011, a pilot operational program was evaluated in Kandal Province, a temephos resistant site. It was concluded that 2 cycles of Bti treatment in the 6 months monsoon season with complete coverage of the target districts achieved an overall dengue case reduction of 48% in the 6 treated districts compared to the previous year, 2010. Five untreated districts in the same province had an overwhelming increase of 352% of dengue cases during the same period of time. The larvicide efficacy, treatment of all in-use containers at the start of the monsoon season, together with treatment coverage of entire districts interrupted disease transmission in the temephos resistant province.

Matched MeSH terms: Pupa/growth & development
Fulltext Distribution pattern of black fly (Diptera: Simuliidae) assemblages along an altitudinal gradient in Peninsular Malaysia

Ya'cob Z, Takaoka H, Pramual P, Low VL, Sofian-Azirun M

Parasit Vectors, 2016 Apr 19;9:219.
PMID: 27094088 DOI: 10.1186/s13071-016-1492-7

BACKGROUND: Preimaginal black flies (Diptera: Simuliidae) are important components of the stream ecosystem. However, there has been limited research undertaken on the vertical distribution of preimaginal black flies and their associated ecological factors. Stream conditions are generally variable along the altitudinal gradient. Therefore, we conducted an in-depth entomological survey to investigate the simuliid distribution pattern along an altitudinal gradient in Peninsular Malaysia.
METHODS: A total of 432 collections were performed in this study (24 samplings at each of 18 fixed-streams at monthly intervals) from February 2012 to January 2014. Larvae and pupae attached on aquatic substrates such as grasses, leaves and stems, twigs, plant roots and rocks were collected by hand using fine forceps. Stream depth (m), width (m), velocity (m/s), water temperature (°C), acidity (pH), conductivity (mS/cm) and dissolved oxygen (mg/L) were measured at the time of each collection.
RESULTS: A total of 35 black fly species were recorded in the present study. The most frequently collected species were Simulium tani (31.7%) and S. whartoni (21.5%), while the relatively common species were Simulium sp. (nr. feuerborni) (16.2%), S. decuplum (15.5%), S. angulistylum (14.8%), S. bishopi (13.2%) and S. izuae (11.8%). Total estimated species richness ranged between 39.8 and 41.3, which yielded more than 80% of sampling efficiency. Six simuliid species were distributed below 500 m, whereas eight species were distributed above 1400 m. Simulium sp. (nr. feuerborni) and S. asakoae were found from middle to high altitudes (711-1813 m). Simulium whartoni, S. brevipar and S. bishopi were distributed widely from low to high altitudes (159-1813 m). Regression analysis between species richness and PCs revealed that the species richness was significantly associated with wider, deeper and faster streams at low altitude, normal water temperature (23-25 °C), low conductivity, higher discharge, more canopy cover and riparian vegetation and with larger streambed particles (F = 20.8, df = 1, 422, P

Matched MeSH terms: Pupa/growth & development
Developmental rate, size, and sexual dimorphism of Megaselia scalaris (Loew) (Diptera: Phoridae): its possible implications in forensic entomology

Zuha RM, Omar B

Parasitol Res, 2014 Jun;113(6):2285-94.
PMID: 24728523 DOI: 10.1007/s00436-014-3883-z

Cosmopolitan scuttle fly, Megaselia scalaris (Loew) (Diptera: Phoridae) is one of the commonest forensic species recorded colonizing human corpse indoors and in concealed environment. The occurrence of this species in such environments provides a higher evidential value to assist estimation of postmortem interval (PMI) compared to other forensically important dipterans. However, developmental and size data of M. scalaris are still lacking and they are derived from a limited range of thermal values. The objective of this study is to develop the growth model of M. scalaris by emphasizing the size range of larvae and puparia at different constant temperatures. This species was reared in six replicates at eight varying constant temperatures ranging from 23 to 36 °C and cow's liver was provided as food source. Larvae and puparia were sampled at set time intervals and measured by their length and weight. Because interpretation of forensic entomological evidence is subject to application of different techniques, development of M. scalaris is expressed herein by using developmental table, length/morphological stage diagrams and linear/nonlinear estimation methods. From the findings, it is very important to highlight that sexual dimorphism of M. scalaris during post feeding larva and pupa stage could be observed based on size and developmental periods. Mean length and weight ratios of male to female puparia are approximately 0.8 and 0.3-0.5, respectively, indicating sexual dimorphism of this species. Developmental period in female are 4.0-11.4 h (post feeding larval stage), 3.7-24.0 h (pupal stage), and 3.0-20.1 h (total developmental period) longer in male. Due to this dimorphism, PMI estimation using M. scalaris post feeding larva or puparium specimens must be carried out carefully by to avoid inaccuracy and misinterpretation.

Matched MeSH terms: Pupa/growth & development
Sexually anomalous individuals of the black fly Simulium trangense (Diptera: Simuliidae) infected with mermithid parasites (Nematoda: Mermithidae)

Ya'cob Z, Low VL, Tan TK, Noor-Izwan A, Lourdes EY, Ramli R, et al.

Parasitol Res, 2021 May;120(5):1555-1561.
PMID: 33655351 DOI: 10.1007/s00436-021-07087-x

Sexually anomalous individuals, typically intersexes or gynandromorphs, bear a mixture of male and female traits. Twelve sexually anomalous individuals of the black fly Simulium (Gomphostilbia) trangense Jitklang, Kuvangkadilok, Baimai, Takaoka & Adler were discovered among 49 adults reared from pupae. All 12 sexually anomalous adults were parasitized by mermithid nematodes, although five additional parasitized adults had no overt external anomalies. Sequence analysis of the 18S rRNA gene revealed that the mermithids, possibly representing a new species, are related to Mesomermis spp., with genetic distances of 5.09-6.87%. All 12 anomalous individuals had female phenotypical traits on the head, thorax, forelegs, midlegs, and claws, but male features on the left and right hind basitarsi. One individual had mixed male and female genitalia. The findings are in accord with the trend that mermithid infections are associated with sexually anomalous adult black flies.

Matched MeSH terms: Pupa/growth & development
Larval growth of Liosarcophaga dux Thompson (Diptera: Sarcophagidae) under uncontrolled indoor temperatures in Malaysia

Kumara TK, Hassan AA, Salmah MR, Bhupinder S

Southeast Asian J. Trop. Med. Public Health, 2013 Mar;44(2):182-7.
PMID: 23691627

The larval growth of Liosarcophaga dux Thompson (Diptera: Sarcophagidae) was studied under varying indoor room temperatures in Malaysia. Five replicates were established. The immature growth of this species from first instar until adult emergence was 307.0+/-3.0 hours. The mean larval length measured for second instar, third instar, post-feeding stage and puparia were 6.5+/-0.5 mm (n=10), 11.8+/-3.7 mm (n=31), 12.7+/-0.8 mm (n=16), and 9.5+/-0.5 mm (n=15), respectively.

Matched MeSH terms: Pupa/growth & development
The inheritance of autogeny in Aedes (Finlaya) togoi (Theobald) from Malaysia and some aspects of its biology

Thomas V, Leng YP

Southeast Asian J. Trop. Med. Public Health, 1972 Jun;3(2):163-74.
PMID: 5082846
Matched MeSH terms: Pupa/growth & development
New species and records of black flies (Diptera: Simuliidae) from Vinh Phuc Province, Vietnam

Takaoka H, Sofian-Azirun M, Ya'cob Z, Chen CD, Lau KW, Pham HT

Zootaxa, 2014;3838(3):347-66.
PMID: 25081781 DOI: 10.11646/zootaxa.3838.3.6

Four new species of black flies are described, and three others are reported as newly recorded, based on adults reared from pupae, pupae and larvae collected in and near Tam Dao National Park, Vinh Phuc Province, Vietnam. New species include Simulium (Gomphostilbia) hongthaii sp. nov., S. (G.) tamdaoense sp. nov. (both species placed in the asakoae species-group), S. (Simulium) taythienense sp. nov. and S. (S.) xuandai sp. nov. (the two latter species placed in the striatum species-group). Newly recorded species are S. (G.) brinchangense Takaoka, Sofian-Azirun & Hashim, S. (Nevermannia) aureohirtum Brunetti and S. (S.) brevipar Takaoka & Davies. These discoveries increase the number of species of black flies known in Vietnam from 21 to 28.

Matched MeSH terms: Pupa/growth & development
Simulium (Nevermannia) khunklangense, a new species of black fly (Diptera: Simuliidae) from Chiang Mai, Thailand

Takaoka H, Srisuka W, Saeung A, Otsuka Y, Choochote W

Zootaxa, 2013;3694:280-8.
PMID: 26312290

Simulium (Nevermannia) khunklangense sp. nov. is described from females, males, pupae and larvae collected in Doi Inthanon National Park, Chiang Mai, Thailand. This new species is placed in the vernum species-group of the subgenus Nevermannia and is similar to S. (N.) chomthongense Takaoka & Srisuka described from Doi Inthanon National Park, Thailand, but is distinguished in the male by the number of enlarged upper-eye facets and the relative width of the hind basitarsus against the hind tibia and femur, and in the pupa by the short common basal stalk of the gill and the cocoon with an anterodorsal bulge or a short anterodorsal projection. Taxonomic notes are provided to separate this new species from five other known species of the vernum species-group, which share an accessory sclerite on the larval abdomen, a rare characteristics in this species-group.

Matched MeSH terms: Pupa/growth & development
Conochironomus (Diptera: Chironomidae) in Asia: new and redescribed species and vouchering issues

Cranston PS

Zootaxa, 2016 May 09;4109(3):315-31.
PMID: 27394867 DOI: 10.11646/zootaxa.4109.3.3

The presence of the Afro-Australian genus Conochironomus Freeman, 1961 (Diptera: Chironomidae) in Asia has been recognised only informally. An unpublished thesis included Conochironomus from Singapore, and the genus has been keyed from Malaysia without named species. Here, the Sumatran Conochironomus tobaterdecimus (Kikuchi & Sasa, 1980) comb. n. is recorded from Singapore and Thailand. The species is transferred from Sumatendipes Kikuchi & Sasa, 1980, rendering the latter a junior synonym (syn. n.) of Conochironomus Freeman. Conochironomus nuengthai sp. n. and Conochironomus sawngthai sp. n. are described as new to science, based on adult males from Chiang Mai, Thailand. All species conform to existing generic diagnoses for all life stages, with features from male and female genitalia, pupal cephalic tubercles and posterolateral 'spurs' of tergite VIII providing evidence for species distinction. Some larvae are linked to C. tobaterdecimus through molecular barcoding. Variation in other larvae, which clearly belong to Conochironomus and are common throughout Thailand, means that they cannot be segregated to species. Larval habitats include pools in river beds, urban storage reservoirs, drains with moderately high nutrient loadings, and peat swamps. Endochironomus effusus Dutta, 1994 from north-eastern India may be a congener but may differ in adult morphology, thereby precluding formal new combination until discrepancies can be reconciled. Many problems with vouchering taxonomic and molecular material are identified that need to be rectified in the future.

Matched MeSH terms: Pupa/growth & development