Among Oriental anopheline mosquitoes (Diptera: Culicidae), several major vectors of forest malaria belong to the group of Anopheles (Cellia) leucosphyrus Dönitz. We have morphologically examined representative material (> 8000 specimens from seven countries) for taxonomic revision of the Leucosphyrus Group. Six new species are here described from adult, pupal and larval stages (with illustrations of immature stages) and formally named as follows: An. latens n. sp. (= An. leucosphyrus species A of Baimai et al., 1988b), An. cracens n. sp., An. scanloni n. sp., An. baimaii n. sp. (formerly An. dirus species B, C, D, respectively), An. mirans n. sp. and An. recens n. sp. Additionally, An. elegans (James) is redescribed and placed in the complex of An. dirus Peyton & Harrison (comprising An. baimaii, An. cracens, An. dirus, An. elegans, An. nemophilous Peyton and Ramalingam, An. scanloni and An. takasagoensis Morishita) of the Leucosphyrus Subgroup, together with An. baisasi Colless and the An. leucosphyrus complex (comprising An. balabacensis Baisas, An. introlatus Baisas, An. latens and An. leucosphyrus). Hence, the former Elegans Subgroup is renamed the Hackeri Subgroup (comprising An. hackeri Edwards, An. pujutensis Colless, An. recens and An. sulawesi Waktoedi). Distribution data and bionomics of the newly defined species are given, based on new material and published records, with discussion of morphological characters for species distinction and implications for ecology and vector roles of such species. Now these and other members of the Leucosphyrus Group are identifiable, it should be possible to clarify the medical importance and distribution of each species. Those already regarded as vectors of human malaria are: An. baimaii[Bangladesh, China (Yunnan), India (Andamans, Assam, Meghalaya, West Bengal), Myanmar, Thailand]; An. latens[Borneo (where it also transmits Bancroftian filariasis), peninsular Malaysia, Thailand]; probably An. cracens (Sumatra, peninsular Malaysia, Thailand); presumably An. scanloni (Thailand); perhaps An. elegans (the Western Ghat form of An. dirus, restricted to peninsular India); but apparently not An. recens (Sumatra) nor An. mirans[Sri Lanka and south-west India (Karnataka, Kerala, Tamil Nadu)], which is a natural vector of simian malarias. Together with typical An. balabacensis, An. dirus and An. leucosphyrus, therefore, the Leucosphyrus Group includes about seven important vectors of forest malaria, plus at least a dozen species of no known medical importance, with differential specific distributions collectively spanning > 5000 km from India to the Philippines.
This study was conducted to clarify the development of free neuromasts with growth of the barramundi, Lates calcarifer. A pair of free neuromasts was observed behind the unpigmented eyes in newly hatched eleutheroembryos with a mean total length of 1.93 mm, and two-hour-old eleuthero-embryos could respond to an approaching pipette. At 2 days after hatching, the egg yolk sac was mostly consumed, the eyes were pigmented, and the larvae commenced feeding on rotifers. Free neuromasts increased in number with growth and commenced developing into canal neuromasts in barramundi 15 days old with a mean total length of 8.07 mm. The average length of the major axis of the trunk free neuromasts attained approximately 12.9-15.5 microm, and the number of sensory cells was 15.4-17.5 at 15-20 days old. Developed cupulae of free neuromasts were observed in 1-day-old eleutheroembryos. The direction of maximum sensitivity of free neuromasts, determined from the polarity of the sensory cells, coincided with the minor axis of the lozenge-shaped outline of the apical surface of the free neuromasts. The polarity of trunk neuromasts was usually oriented along the antero-posterior axis of the fish body, but a few had a dorso-ventral direction. On the head, free neuromasts were oriented on lines tangential to concentric circles around the eye.
This study was conducted to analyze variation in Strombus canarium larvae development, growth and survivals when cultured during wet (main reproductive period) and dry seasons. Larvae were reared at 200 larvae L(-1) in filtered seawater (0.22 microm) and fed with Isochrysis galbana at 1000 cells mL(-1) ad libitum. The culture environment was maintained at 29 +/- 1 degrees C, salinity of 30 +/- 1 PSU and photoperiod of 12:12 light dark cycle. Growth of the larvae was described on a length-at-age basis using the modified Gompertz regression. There was high correlation in shell length-at-age relationship for both wet season (R2 = 0.99) and dry season (R2 = 0.98) culture experiments. The maximal growth rate (M) and survival rate (S) were higher for larvae cultured during wet season (M = 62.44 microm day(-1), S = 14.36-2.31%), compared with dry season (M = 43.05 microm day(-1), S = 5 +/- 1.15%). The maximal attainable larval size (a) was however lower during wet season (950.19 +/- 66.93 microm shell length) compared with dry season (1343.05 +/- 586.51 microm shell length), which might be due to significantly low larvae density in the latter. Further studies are needed to investigate variation in bio-chemical composition of the egg mass, which was suggested as the main reason for the differences.
Hypopygiopsis violacea, a species of fly of forensic importance, was recovered from a corpse and described for the first time. The morphological structures of the second and third instar larvae of four specimens were examined using light microscope. Observations were focused on three main morphological characters: cephalopharyngeal skeleton, anterior and posterior spiracles. Cephalopharyngeal skeleton of second instar larva is darkly pigmented and without accessory sclerite below the mouth hook. The anterior spiracles of second and third instar larvae have 8-9 papillae each, arranged in a single row. The posterior spiracle of second instar larva has two spiracular slits with no thickening of peritreme. This differentiates it from the third instar, whereby the latter has three slits for each posterior spiracle. Cephalopharyngeal skeleton of third instar larva is heavily pigmented. An accessory sclerite is found below the hook part of third instar larva but is absent in second instar. Peritreme of the posterior spiracle of third instar larva is thick almost complete encircling a button. The intersegmental spines of the cuticular surface are dome-shaped and unicuspid. Third instar larva of this species is large with size approximately 15 mm long. These findings provide important identification features of immature stages of Hy. violacea which could be useful in forensic entomology.
Simulium (Gomphostilbia) sofiani sp. nov. is described on the basis of reared adult female, male, pupal and larval specimens collected from Cameron Highlands, Pahang state, Malaysia. This new species is placed in the ceylonicum species-group within the subgenus Gomphostilbia and is easily distinguished from all the related known species by the combination of the following characteristics: an elongate sensory vesicle and yellow hair tuft on the stem vein of the wing in the female, the greater number of large upper-eye facets (15 or 16 vertical columns and 15 or 16 horizontal rows) and almost entirely darkened hind basitarsus in the male, and the gill bearing a long common basal stalk and 8 filaments arranged as [(1+2)+(1+2)] +2 filaments from dorsal to ventral in the pupa.
Two new species of black flies, Simulium (Comphostilbia) terengganuense sp. nov. and Simulium (Gomphostilbia) aziruni sp. nov. (Diptera: Simuliidae), are described on the basis of reared adult, pupal, and larval specimens collected from Peninsular Malaysia. Both species are placed in the batoense species-group within the subgenus Gomphostilbia, one of two dominant subgenera of the genus Simulium in Peninsular Malaysia as well as in the Oriental Region. Strikingly, three morphological characteristics that rarely occur in the subgenus Gomphostilbia are found in these two new species: the very narrow female frons and the mushroom-like pupal terminal hooks in S. (G.) terengganuense sp. nov. and the pupal gill composed of an inflated horn-like structure and eight slender filaments in S. (G.) aziruni sp. nov.
Simulium (Simulium) kisapense sp. nov. is described on the basis of reared adult, pupal, and larval specimens collected from Langkawi Island, Peninsular Malaysia, and placed in the multi-striatum species-group in the subgenus Simulium. This new species is characterized by the bare basal section of the female radial vein, the male ventral plate with setae, the eight pupal gill filaments divergent at an angle of >90 degrees, and the shoe-shaped cocoon with small lateral window(s). Taxonomic notes are given to separate this new species from S. (S.) hirtinervis Edwards and S. (S.) malayense Takaoka and Davies, both from Peninsular Malaysia, and several other known species from Bhutan, India, Nepal, and Thailand.
Simulium (Asiosimulium) furvum sp. nov. (Diptera: Simuliidae) is described from female, male, pupal, and larval specimens collected from Maewa National Park, Lampang Province, Thailand. This new species represents the fourth member of the subgenus Asiosimulium Takaoka & Chochoote, one of two small black fly subgenera endemic in the Oriental Region. It is characterized by a pear-shaped spermatheca in the female; a ventral plate in the male with a laterally compressed median keel directed ventrally and with a deep notch posteromedially, and aedeagal membrane with stout spines; and by 22 gill filaments in the pupa. Taxonomic notes are provided to separate this new species from three known species, Simulium (Asiosimulium) oblongum Takaoka & Choochote and Simulium (Asiosimulium) wanchaii Takaoka & Choochote, both from Thailand, and Simulium (Asiosimulium) suchitrae Takaoka from Nepal.
ABSTRACT A new black fly species, Simulium (Comphostilbia) langkawiense, is described based on adult female, adult male, pupal, and larval specimens collected from Langkawi Island, Malaysia. This new species is similar in the configuration of the pupal gill to Simulium (Comphostilbia) gombakense Takaoka & Davies, 1995, originally described from Peninsular Malaysia, but differs from the latter species by the female genital fork with an anterolaterally angulated plate on each arm, the female tarsal claw tooth shorter than one half of the claw, the small number of male upper-eye large facets, the ventral plate with its ventral margin nearly flat in the middle when viewed posteriorly, and the inflated structure of the pupal gill with a less produced middle portion (width of middle inflated portion: length of inflated structure = 0.24). Taxonomic notes are also given to separate this new species from two other related species from Nepal and India. This represents another example of a unique species of black fly on one of the continental islands of Peninsular Malaysia.
Simulium (Comphostilbia) izuae sp. nov. is described from female, male, pupal, and larval specimens collected from Cameron's Highlands, Peninsular Malaysia. This new species is placed in the asakoae species-group of the subgenus Gomphostilbia. The pupa of this new species is characterized by the gill with eight long filaments arranged as (3 + 3) + 2 filaments, of which the ventral pair of filaments is borne on a stalk that is always shorter than the common basal stalk. Taxonomic notes to distinguish this new species from five other Malaysian species and 12 other species of the asakoae species-group from other countries are given. Keys to identify all 18 species of the asakoae species-group are also provided for females, males, pupae, and mature larvae.
Hard ticks taken from the Japanese serow, Capricornis crispus, in Yamagata Prefecture, Honshu, harboured infective larvae of onchocercid filariae after incubation from the 22nd to the 158th day. Haemaphysalis flava and H. japonica contained one to eight filarial larvae; females, males and a nymph of the ticks were infected. The 44 infective larvae recovered were 612-1,370 μm long, and 11 of them, 930-1,340 μm long, were studied in detail. The larvae possessed the morphologic characteristics of the larvae of the genus Cercopithifilaria, namely an oesophagus with a posterior glandular part, no buccal capsule and a long tail with three terminal lappets. Five types (A to E) of infective larvae were identified based on the morphologic characteristics. While to date five species of Cercopithifilaria have been described from the Japanese serow, a specific identification of the larvae found in this study was generally not possible. Only type E larvae could be tentatively assigned to Cercopithifilaria tumidicervicata, as they had a cervical swelling similar to that of the adults of this species. A key for the identification of the five larval types is presented. The study presents circumstantial evidences indicating that H. flava and H. japonica may transmit Cercopithifilaria spp. to Japanese serows. It also suggests the possibility that such filarial larvae will be found in hard ticks anywhere, because Cercopithifilaria is distributed worldwide, though this genus generally goes unnoticed, as its microfilariae occur in the skin, not in the blood, of host animals.
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.
Two new blackfly species, Simulium (Gomphostilbia) azhari and Simulium (Gomphostilbia) johorense, are described based on adult females, males, pupae, and larvae collected from Peninsular Malaysia, and assigned to the parahiyangum subgroup and the duolongum subgroup of the batoense species group of the subgenus Comphostilbia, respectively. S. (G.) azhari sp. nov. is characterized in the female by the narrow frons, and in the male by the broad style and the ventral plate moderately produced ventrally. S. (G.) johorense sp. nov. is also remarkable in having the female subcosta lacking hairs or bearing a reduced number of hairs ranging from one to five. The pupae of both new species share a similar arrangement of the eight gill filaments (i.e., stalks of dorsal and middle triplets and ventral pair arising at the same level from the short common basal stalk), although relative lengths of filaments of the ventral pair to those of the dorsal and middle triplets are different between the two new species. Taxonomic notes are given to distinguish these new species from other related species. Keys to identify all 10 species of the batoense species group in Peninsular Malaysia are provided for adult females, males, pupae, and mature larvae.
Simulium (Gomphostilbia) leparense sp. nov. is described from females, males, and pupae collected from Peninsular Malaysia. This new species is assigned to the ceylonicum species-group of the subgenus Gomphostilbia, and is characterized by the female and male scuta covered with dark-brown short hairs, smaller number of male upper-eye facets, presence of shiny paired spots on the male abdominal segments 2-8, and absence of grapnel-shaped hooklets on the pupal abdominal segment 9. The male and pupa of S. capillatum Takaoka, which was originally described from larvae collected from Sarawak and Sabah, are described for the first time. Keys to identify all 32 species of the Simulium ceylonicum species-group including 27 species from other countries are provided for females, males, pupae, and mature larvae.
Simulium (Simulium) lomkaoense sp. nov. is described from females, males, pupae, and larvae in Thailand. This new species is assigned to the Simulium malyschevi Dorogostaisky, Rubtsov & Vlasenko species-group of the subgenus Simulium, and appears to be closely related to Simulium baimaii Kuvangkadilok & Takaoka from Thailand in having a similar shape of the female and male genitalia, pupal gill with two inflated filaments, and simple wall-pocket-shaped cocoon. This new species is compared taxonomically with S. baimaii and other related species. It represents the third species of the S. malyschevi species-group known from Thailand.
Preservation of larvae retrieved from cadavers is important in ensuring the quality and integrity of entomological specimens used for the estimation of post-mortem interval (PMI). The process of killing and preserving larvae could distort the larvae leading to inaccurate estimation of PMI. In this study, the effects of killing Chrysomya megacephala larvae with hot water at different temperatures and subsequent maintenance in various preservatives were determined. Larvae not killed by hot water but preserved directly were used as control. The types of preservative used were 10% formalin, 70% ethanol and Kahle's solution. The morphological features examined were length, turgidity, curvature and coloration of larvae. Larvae killed in 80ºC hot water have shorter mean length (12.47 ± 2.86 mm) compared to those in 60ºC hot water (12.95 ± 2.69 mm). Increasing the duration of preservation in all types of preservative caused elongations of larvae treated or untreated with hot water. There were no significant changes in larval turgidity preserved in Kahle's solution compared to other two preservatives and were unaffected by the duration of storage. Larvae preserved in Kahle's solution experienced the least changes in coloration and shape compared to other preserved larvae in 70% ethanol or 10% formalin. Larvae directly immersed alive in 70% ethanol experienced the most changes in curvature, coloration and turgidity. This study suggested that killing larvae with hot water at 80ºC and preservation in Kahle's solution is the optimum method resulting in least changes in morphological features of Ch. megacephala larvae.