Redescription of the tiger beetle Cicindelidia aeneicollis (Bates 1881) (Coleoptera: Cicindelidae) and discovery of new morphological variants from the Pacific Slope of Mexico.

The tiger beetle species, Cicindelidia aeneicollis (Bates 1881) is redescribed, as Bates original description was inadequate and did not accurately capture the character states or variation found within the species. The specific epithet aeneicollis is partially misleading as the proepisternum is mostly aeneous (bronze/copper) with the basal quarter to third being polychromatic, which the description does not convey. Some populations of this species from the western coast of Mexico exhibit significant variation in maculations, with individuals ranging from weakly marked (as in Bates description) to much more extensively marked.

Evaluation of an I-box wind tunnel model for assessment of behavioral responses of blow flies.

The behavioral response of flies to olfactory cues remains the focus of many investigations, and wind tunnels have sometimes been employed for assessment of this variable in the laboratory. In this study, our aim was to design, construct, and operate a new model of I-box wind tunnel with improved efficacy, highlighting the use of a new wind tunnel model to investigate the behavioral response of the medically important blow fly, Chrysomya megacephala (Fabricius). The I-box dual-choice wind tunnel designed for this study consists of seven conjoined compartments that resulted in a linear apparatus with clear glass tunnel of 30 × 30 × 190 cm ended both sides with wooden "fan compartments" which are equipped with adjustable fans as wind source. The clear glass tunnel consisted of two "stimulus compartments" with either presence or absence (control) of bait; two "trap compartments" where flies were attracted and allowed to reside; and one central "release compartment" where flies were introduced. Wind tunnel experiments were carried out in a temperature-controlled room, with a room light as a light source and a room-ventilated fan as odor-remover from tunnel out. Evaluation of testing parameters revealed that the highest attractive index was achieved with the use of 300 g of 1-day tainted pork scrap (pork meat mixed with offal) as bait in wind tunnel settings wind speed of 0.58 m/s, during 1.00-5.00 PM with light intensity of 341.33 lux from vertical light and 135.93 lux from horizontal light for testing a group of 60 flies. In addition, no significant response of well-fed and 24 h staved flies to this bait under these conditions was found. Results of this study supported this new wind tunnel model as a suitable apparatus for investigation of behavioral response of blow flies to bait chemical cues in the laboratory.

Morphological descriptions for the identification of Hypopygiopsis tumrasvini Kurahashi (Diptera: Calliphoridae).

This article presents morphological descriptions of larvae and adults of Hypopygiopsis tumrasvini Kurahashi (Diptera: Calliphoridae), a blow fly species that may be of forensic importance. Both second and third instar larvae are illustrated, with emphasis placed on important characteristic features used for larval identification, such as the cephalopharyngeal skeleton, anterior and posterior spiracles, and dorsal spines between the prothorax and mesothorax. Eight to 11 papillae were found on each anterior spiracle arranged in a single row. The dorsal spines between the prothorax and mesothorax were arranged in sets of posteriorly projecting acuminate spines with darkly pigmented tips. The posterior spiracles each bear three prominent and separated long, slender spiracular slits encircled by a dark, thick peritreme that is complete ventromedially around a button. Prominent inner projection of peritreme is seen between the middle and lower spiracular slits. A previously published key for differentiating third instar larvae of flies of possible forensic importance in Thailand is updated to include this additional species. Some characteristic features of males and females of the species are also provided.

External morphology of Chrysomya pinguis (Walker) (Diptera: Calliphoridae) revealed by scanning electron microscopy.

The external morphology of the adult female blow fly, Chrysomya pinguis (Walker, 1858), was examined using scanning electron microscopy. Ultrastructure of the compound eye, ocellus, antenna, palpus, spiracles and portions of the thorax was highlighted. A great difference was observed in sculpture patterns of the corneal lens surface of the ommatidia of the compound eye and that of the ocelli, with the former being densely pustulate and the latter extremely sinuous. Several sensilla types were observed in this study including: sensilla chaetica, sensilla trichodea, sensilla basiconica and sensilla coeloconica. Their probable functions are discussed with reference to other literature. Morphological information about C. pinguis that was revealed in this study allows us to know such types of structures in much better detail and may eventually provide a basis for understanding some of the biological behavior of this fly species in the future.

Sensilla of the antenna and palp of Hydrotaea chalcogaster (Diptera: Muscidae).

Hydrotaea chalcogaster is a fly species of medical and forensic importance in many parts of the world. In this study, we investigated the sensilla of the antenna and palp of the adult female fly using scanning electron microscopy. The antennal scape has one type of sensillum, the sharp-tipped sensillum trichodeum; whereas, the antennal pedicel also possessed this type of sensillum in addition to an unidentified type. Three types of sensilla were found on the flagellum: (1) sensilla basiconica, with both large and small sensilla basiconica showing wall pores, (2) sensilla coeloconica, with a smooth surface, and (3) sensory pits, with wall pores of pegs. The arista is located dorso-laterally on the flagellum and has three segments. Short microtrichia are located around the distal end of its second segment and on the proximal half of the third segment. Both large sharp-tipped sensilla chaetica and small sensilla basiconica with wall pores were observed on the palps. Results of this study contribute to our overall understanding of the ultrastructural morphology of sensilla on the antenna and palp of H. chalcogaster.

Morphological Characteristics of Terminalia of the Wasp-Mimicking Fly, Stomorhina discolor (Fabricius).

Stomorhina discolor (Fabricius), a species of blow fly that mimics wasps, is distributed worldwide, but detailed information about characteristics of its adult terminalia is incomplete. To help fill this gap in the information, the morphology of adult stages of S. discolor was investigated using light microscopy and scanning electron microscopy. Observations using the light microscope revealed unique characteristics of the male genitalia that are markedly different from other blow fly species. More morphological detail, including observation of several sensilla (e.g., sensilla trichoid and sensilla basiconica) along the male terminalia and female ovipositor, was seen under the scanning electron microscope. These details can be taxonomically valuable for identifying males and females of S. discolor and may help address matters concerning copulation in this species.

Ultrastructure of eggs of Paracapillaria (Crossicapillaria) philippinensis and evidence related to its life cycle.

The varied ultrastructure of the eggshell of Paracapillaria (Crossicapillaria) philippinensis, collected from a human sample, is reported from a scanning electron microscopy study. Two distinct egg shapes were identified: typical peanut-shaped and swollen peanut-shaped. Both thick and thin eggshells were detected. Thick eggshells are either fairly smooth or bear a beam-like network in relation to the pillars in their surface ultrastructure. Thin eggshells are transparent allowing visibility of the coiled larva within. Presence of the thin shell provides supportive evidence of autoinfection involved in the life cycle of this medically important parasite.

Ultramorphology of eggshell of flesh fly Liosarcophaga dux (Diptera: Sarcophagidae).

Eggs of Liosarcophaga dux (Thomson) (Diptera: Sarcophagidae) are elongated and slightly bean-shaped, measuring approximately 1.5 mm in length. Each is covered externally by an eggshell comprised of polygonal patterns. In this study, scanning and transmission electron microscopy were used to examine the eggshell of this species of flesh fly for the first time. No plastron region or median area was detected. Ultrathin sectioning of the eggshell revealed multiple layers in the shell that could be observed using transmission electron microscopy.

Larval morphology of Chrysomya nigripes (Diptera: Calliphoridae), a fly species of forensic importance.

The morphology of all instars of Chrysomya nigripes Aubertin, a blow fly species of forensic importance, is presented with the aid of both light microscopy and scanning electron microscopy (SEM). Morphological features of the cephalopharyngeal skeleton, anterior spiracle, posterior spiracle, and dorsal spines between the prothorax and mesothorax are highlighted. No consistent features were found, even using SEM, for distinguishing the first instar of C. nigripes from that of Chrysomya megacephala (F.) or Chrysomya rufifacies (Macquart), two other commonly associated blow fly species in corpses in Thailand. Several features observed in second and third instars proved to be valuable characteristics for separating these species.

Ultrastructure of the ommatrichia in Megaselia scalaris (Loew) (Diptera: Phoridae).

Using both scanning electron microscopy (SEM) and transmission electron microscopy (TEM), the ommatrichia, or hair-like processes that are located between the facets of the compound eye, were examined on an adult male Megaselia scalaris (Loew) fly. Each ommatrichium was observed to be a tapering structure bearing a longitudinally grooved cuticle and are anchored tightly in flexible sockets. Ultrathin sectioning and TEM revealed a thick wall in the ommatrichia, and their function was proposed to be mechanoreception based on characteristics from both SEM and TEM observations.

Evaluation of habitat management strategies for the reduction of malaria vectors in northern Belize.

Mowing and burning of emergent vegetation were evaluated as potential management strategies for the control of the malaria vector, Anopheles vestitipennis, in northern Belize, Central America. The primary aim was reduction of tall dense macrophytes (dominated by Typha domingensis) as preferred larval habitat for An. vestitipennis. Nine experimental plots were established in a Typha marsh in Orange Walk District, Belize. Three plots were burned, three were treated by subaquatic mowing, and three were unaltered controls. After treatment, Typha height was most dramatically affected by the mow treatment. Plant heights at 21 and 95 days post-treatment reflected an 89% and 48% decrease, respectively, compared to pretreatment conditions. The Typha height in the burn plots was not as severely affected. Heights at 21 days post-treatment were 39% lower than those of pre-treatment vegetation, with a return to near pre-test heights by 95 days post-treatment. Both treatments resulted in a significant reduction in the number of An. vestitipennis larvae collected as compared to control plots. Conversely, the treatments resulted in increased larval densities of several other vector and pest mosquito species. Larval population densities ofAn. albimanus, Ochlerotatus taeniorhynchus, and Culex coronator were significantly higher in burn plots. In mow plots, there were significant increases in An. albimanus and Oc. taeniorhynchus larval populations. Non-target invertebrate species affected by the treatments were adult Tropisternus collaris, larval Corythrella, and adult Parapleapuella.

Surface ultrastructure of Chrysomya rufifacies (Macquart) larvae (Diptera: Calliphoridae).

The surface ultrastructure of all larval instars of Chrysomya rufifacies (Macquart) is described by means of scanning electron microscopy (SEM). Morphological changes were greatest from the first to the second instar, but less from the second to the third instar. Most of these changes involved the structure of the anterior spiracle, posterior spiracle, integument of the body, and mouthhooks. Modification of the mouthhooks, especially in the third instar, are helpful in explaining the ferocious feeding ability of the older maggots. The common name of "hairy-maggot" for C. rufifacies is only appropriate for the second and third instars because of their elongated tubercles along the body, whereas this name is not descriptive of the first instar that lack tubercles.

Mouthparts of Megaselia scalaris (Loew) (Diptera: Phoridae).

Mouthparts of adult Megaselia scalaris (Loew), a fly species of medical importance, were examined using scanning electron microscopy. Sexual dimorphism of the labellum was observed in the mouthpart structures of this species. The labella of males were clothed with a dense covering of microtrichia, but these were found to be entirely absent from the labella of females. Aside from this difference, trichoid and conical sensilla that are most likely used as taste or contact chemoreceptors appear on the labellum and labrum of both sexes. In addition, five pairs of sharply pointed teeth at the ventral surface of the labellum is another feature that is shared by the two sexes. A plausible feeding mechanism for this fly is also advanced.

Larval ultrastructure of Parasarcophaga dux (Thomson) (Diptera: Sarcophagidae).

Ultrastructure of all larval instars of Parasarcophaga dux (Thomson), a common flesh fly species in Thailand, is presented using scanning electron microscopy. Special attention is given to the structure of anterior and posterior spiracles since these are important features used to differentiate between other sarcophagids. Each anterior spiracle in second and third instars has a single row of papillae varying in number from 14 to 17. The posterior spiracular discs have incomplete peritremes, with a prominent inner arc. Three long, narrow spiracular slits are oriented more or less vertically in each spiracular disc of third instar. Posterior spiracular hairs lack extensive branching and emanate approximately midway down the length of each slit. Microscopic morphology of the mouthhooks markedly differs between the first and second instars. The structure of these mouthhooks supports this fly species as being necrophagous or capable of producing myiasis.

Prestomal teeth of some flies of medical importance.

Comparison of prestomal teeth of adult Chrysomya megacephala, Chrysomya rufifacies, Chrysomya nigripes, Lucilia cuprina, Parasarcophaga dux and Musca domestica was accomplished by use of scanning electron microscopy. The prestomal teeth of C. megacephala, C. rufifacies, L. cuprina and P. dux are all similar in appearance in having various degrees of bifurcation at their tips. In contrast, the tips of the prestomal teeth in C. nigripes are very shallowly serrated, but are comparatively more deeply serrated in M. domestica. These features may help account for the roles these flies may play in matters of medical or veterinary importance, such as causing physical irritation or acting as vectors of disease agents.

Antennal sensilla of some forensically important flies in families Calliphoridae, Sarcophagidae and Muscidae.

Antennal sensilla of some forensically important fly species in the families Calliphoridae (Chrysomya megacephala, Chrysomya rufifacies, Chrysomya nigripes and Lucilia cuprina), Sarcophagidae (Parasarcophaga dux) and Muscidae (Musca domestica) were studied using scanning electron microscopy. Five types of sensilla were observed: trichoid, basiconic, coeloconic, styloconic and sensory pit. Only trichoid sensilla are found on the scape of the antenna, while both trichoid and styloconic sensilla are located on the antennal pedicels of all species studied. Basiconic sensilla are the most numerous of the sensilla found on the antennae of both sexes of all fly species studied and are comprised of two subtypes: large and small basiconic sensilla. Coeloconic sensilla are characterized by short pegs, with either grooved or smooth surfaces, that are sunken into deep depressions. No marked difference was observed in the number, morphological structure or distributional pattern of any of the sensilla among the species studied, with the exception of there being more numerous sensory pits detected in female P. dux compared to the other species. The suggested function of each antennal sensillum was based on comparison with results of other investigations on similar sensilla.

Observations on first and second-instar larvae of Megaselia scalaris (Loew) (Diptera: Phoridae).

The ultrastructure of the first and second-instar larvae of Megaselia scalaris (Loew) was studied using scanning electron microscopy (SEM). Significant changes in morphological features were observed in the anterior and posterior spiracles, but only minimal changes in the labium and mouthhooks were seen. The ultrastructure of M. scalaris larvae not only provides chronological transformation of their larval instars, but it can also be used to explain their feeding behavior and mode of respiration. In addition, morphological structures useful for specific identification of first or second-instar larvae collected from human corpses may be used in forensic investigations.

Larval morphology of Chrysomya megacephala (Fabricius) (Diptera: Calliphoridae) using scanning electron microscopy.

The larval morphology of Chrysomya megacephala (Fabricius) is presented using scanning electron microscopy (SEM). Extreme similarity of this species to Chrysomya rufifacies (Macquart), a species usually found concurrently inhabiting decomposing human corpses in Thailand, is seen only in the first-instar larvae. The relative thickness of the branches of the posterior spiracular hairs in these species could be used to differentiate them in this developmental stage. In contrast, the "hairy" appearance of C. rufifacies allows second- and third-instar larvae to be easily distinguished. Results of this study should help in future endeavors to differentiate C. megacephala from other larvae found in decomposing human corpses in Thailand.

Alimentary Canal of the Adult Blow Fly, Chrysomya megacephala (F.) (Diptera: Calliphoridae)-Part I: Ultrastructure of Salivary Glands.

The salivary gland ultrastructure of the adult male blow fly, Chrysomya megacephala (F.) (Diptera: Calliphoridae), was investigated at the ultrastructural level using light microscopy (LM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The salivary glands are paired structures composed of a single median deferent duct bifurcated into two long, narrow efferent ducts connected to the coiled tubular glands. The SEM image of the gland surface revealed that the basal lamina is relatively smooth in general, but the whole surface appeared as a trace of rough swollen insertion by intense tracheal ramification. Ultrastructurally, the salivary gland is enclosed within the basal lamina, and interdigitation cytoplasmic extensions were apparent between the adjacent gland cells. The basement membrane appeared infoldings that is similar to the complex of the labyrinth channel. The cytoplasm characteristic of the gland revealed high activity, based on the abundance of noticeable secretory granules, either singly or in an aggregated reservoir. In addition, mitochondria were found to intersperse among rich parallel of arrays rough endoplasmic reticulum. Thick cuticle, which was well-delineated and electron dense, apically lined the gland compartments, with discontinuity of the double-layer cuticle revealing a trace of secretion discharged into the lumen. Gross anatomy of the adult salivary gland was markedly different from that of the third instar of the same species, and structural dissimilarity is discussed briefly.

Alimentary canal of the blow fly Chrysomya megacephala (F.) (Diptera: Calliphoridae): an emphasis on dissection and morphometry.

The alimentary canal is a major organ system that is often involved in the transmission of pathogens to humans from insects that serve as vectors of disease. In this study, we investigated the alimentary canal of the blow fly, Chrysomya megacephala (F.) (Diptera: Calliphoridae), highlighting the description for dissection and morphometric analysis of each organ. Dissection was performed in a phosphate buffer solution (pH=7.4) on 3(rd) instar larvae (three to four days old) and on both male and female adults (seven days old). Larval dissection was accomplished using two fine forceps to open the specimens from the posterior end and proceed anteriorly toward the cephalic segment. Meticulous dissection of the anterior end was vital for observation of the delicate salivary ducts, crop duct, and esophagus. Overall length of the 3(rd) instar alimentary canal measured 89.15 mm (range 81.40-99.70 mm). The midgut comprised the longest portion, measuring 46.35 mm (range 40.00-52.00 mm; n = 30) of the entire canal. Adult dissection was also performed from abdomen to head. Morphometric analyses revealed that the alimentary canal of males and females were relatively similar. No statistical differences were found between the entire length of the alimentary canal from mouth to anus (excluding all branches of the salivary glands, crop, and Malpighian tubules) of males and females. The alimentary canals of males measured 36.23 mm (range 32.60-41.20 mm) in length; whereas, those of females measured 37.23 mm (range 32.70-42.15 mm). Two-thirds of the entire canal length was comprised of midgut in each sex.