Longitudinal Ridges Research Articles

Leioproctus zephyr Prendergast (Hymenoptera, Colletidae, Leioproctus), an oligoletic new bee species with a distinctive clypeus

A new speciesLeioproctus zephyr(Hymenoptera: Colletidae) is described from both sexes.Leioproctus zephyrsp. nov.is remarkable in featuring a large longitudinal ridge on the clypeus. This diagnostic morphological feature present in both sexes, along with various other distinctive characters including the male genitalia, female hind-tibial spur, and glossa morphology, clearly distinguish this species from all otherLeioproctus. Along with these unique traits,L. zephyrcannot be classified into any of the existing subgenera ofLeioproctus, sharing some, but not all, of the characters of the subgeneraCeratocolletes,Charicolletes,ProtomorphaandOdontocolletes. DNA barcoding with the CO1 gene confirmed the sexes belonged to the same species and it did not match any previously barcoded species. This species is restricted to native vegetation remnants in the southwest Western Australian biodiversity hotspot, and is highly specialised, foraging only on a few species in the genusJacksonia(Fabaceae). The unusual clypeus may be an adaptation for foraging on the keeled papilionaceous flowers. The limited number of sites this species has been collected from and its oligolectic diet suggestL. zephyrshould be considered to be a species of conservation concern. Further taxonomic research is required to determine the phylogenetic position of this unusualLeioproctus.

Morphology of larvae and pupae of the genus Autocrates (Coleoptera: Trictenotomidae) and its phylogenetic implications

The trictenotomid genus Autocrates Thomson, 1860 is remarkable for its large and robust adults, but its larval morphology and bionomics have been unknown over the last 160 years. Here, we describe and illustrate in detail the eggs, and also the first and last instar larva and the pupa of Autocrates maqueti Drumont, 2006, based on specimens reared from identified adults collected in South Korea. The first instar larva is very similar to the known trictenotomid larvae of the genus Trictenotoma Gray, 1832, sharing the following features: distinctly flattened and parallel-sided, well-sclerotized head and largely unpigmented postcephalic body, lyre-shaped frontal arms, very short coronal suture, five pairs of stemmata, asymmetrical and tridentate mandibles with mola, simple and apically upturned urogomphi, and absence of longitudinal ridges on the thorax and abdomen. Differences occur in the primary chaetotaxy. The last instar larva is almost identical with Trictenotoma in general appearance, but the longitudinal tergal ridges of Autocrates are much denser and more widely distributed than those of Trictenotoma. Our preliminary assessment of features of immature stages confirms a close relationship of Trictenotomidae with the “salpingid group”, i.e. Salpingidae, Boridae, Pyrochroidae and Pythidae. A sister group relationship with Pythidae is likely. The putative synapomorphy is the subdivision of the ventral element of tergites IX, even though this condition is not visible in the first instars of Autocrates, and quite indistinct (but recognizable) in the last larval stage. The complete mitochondrial genome of A. maqueti is provided. A preliminary phylogenetic analysis of trictenotomid species is presented using two mitochondrial genes (16S and COI). The morphology of eggs and biological information on feeding and oviposition behaviors are also provided with photographs of adults and eggs.

Effect of dietary replacement of fish meal by poultry by-product meal on the growth performance, immunity, and intestinal health of juvenile red swamp crayfish, procambarus clarkia

The present study was conducted to investigate the dietary replacement of fish meal with poultry by-product meal (PBM) on the growth performance, immunity, antioxidant properties, and intestinal health of red swamp crayfish (Procambarus clarkia). A diet containing 20% fish meal (FM) and complex plant ingredients as the main protein resources was set as the FM group (crude protein 32%, crude lipid 6%). Four diets replacing 25%, 50%, 75%, and 100% fish meal of the FM diet with PBM were set as the PBM25, PBM50, PBM75, and PBM100 groups, respectively. Compared to the FM group, the PBM100 diet significantly decreased growth performance and feed utilization of crayfish, while markedly increasing the activity of serum aspartate aminotransferase. The immune response was depressed in crayfish fed the PBM100 diet as the activities of serum lysozyme and phenoloxidase, gene expression of anti-lipopolysaccharide factors (alf), cyclophilin A (cypa), crustin, and hemocyanin-1 (hep-1) in hepatopancreas were remarkably decreased. The activities of antioxidases and expression of antioxidant-relevant genes in the hepatopancreas were not influenced by PBM inclusion. Crayfish fed different diets exhibited no obvious symptoms of enteritis, but the PBM100 diet destructed intestinal morphology by significantly decreasing the average length of longitudinal ridges. The α-diversity and overall community structure were not significantly influenced but variations were found in the relative abundance of some genera by PBM inclusion. In summary, CAP could successfully replace 75% dietary FM in a basal diet containing 20% fish meal, while higher CAP level compromised growth performance, immunity, and intestinal histology of crayfish.

Spatial Variation in Soil Physico-Chemical Properties along Slope Position in a Small Agricultural Watershed Scale

Both cropland management and slop erosion are important factors influencing soil properties, but there are relatively few studies on their combined effects. Studies at the agricultural watershed scale can satisfy both of these conditions, and to reduce the effects of soil heterogeneity due to differences in spatial scale, it is better to select different slopes in the same small watershed. To understand how soil properties will respond to the variation of slope position and cropland management at an agricultural watershed, we present the distribution of soil bulk density (BD), saturated hydraulic conductivity (Ks), water-stable aggregates, soil organic carbon (OC), nitrogen (N), and phosphorus (P) at four slope positions in two cropland management systems of a small agricultural watershed in the black soil region of northeast China. The selected four slope positions include upper slope, middle slope, lower slope, and footslope positions. The two cropland management systems consist of a sustainable cropland system (i.e., contour ridge tillage at upper slope position, longitudinal ridge tillage at middle slope and lower slope positions, and grassland at footslope position) and a conventional cropland system (i.e., contour ridge tillage at upper slope position, longitudinal ridge tillage at middle slope, lower slope positions, and footslope positions). The results showed that soil bulk density and microaggregates decreased but the concentration of OC and nutrients, Ks, and small-macroaggregate increased from the upper slope position to the lower slope position in both the conventional and sustainable croplands, which was due to the interaction effect of cultivation with erosion. In comparison with conventional cropland, sustainable cropland has greater Ks, large-macroaggregate, small-macroaggregate, microaggregate, and concentrations and stocks of OC, N, and P, but showed lower bulk density and silt + clay fraction. However, the prominent differences in both croplands were presented in the footslope position, which is ascribed to the interaction of cultivation, erosion, and cropland management. These results highlighted that sustainable cropland management practice has the potential to improve soil structure and prevent soil and nutrient loss.

Clitopilus chichawatniensis sp. nov. (Entolomataceae, Agaricales) from Pakistan

A novel mushroom species occurring on loamy soil under Bombax cieba was collected from Chichawatni forest, Punjab, Pakistan. Phylogenetic analyses of the nrDNA ITS and nuLSU regions revealed that it clusters within the genus Clitopilus. Further morpho-anatomical analyses confirmed its uniqueness, which is referred as a new species under the name Clitopilus chichawatniensis. The distinguishing characteristics of this novel taxon are large whitish to light pale, eccentric pleurotoid pileus 50–65 mm wide with lobed and involuted margins, large ovoid to ellipsoid basidiospores 6.2–8.4 × 4.8–6.4 µm with 3–5 longitudinal ridges, absence of cheilocystidia and pleurocystidia. A detailed description of this taxon and a key to all existing species of the genus Clitopilus in Pakistan is provided.

A new species of the grenadier genus Coelorinchus (Gadiformes: Macrouridae) from the western Indian Ocean

A new species, Coelorinchus tricristiger sp. nov., is described from the western Indian Ocean off Socotra and Somalia. It belongs to the Coelorinchus hubbsi group of the subgenus Quincuncia. The modified scales on top of the postorbital portion of head forming a prolonged longitudinal ridge, in combination with its distinctive body markings and the absence of a ventral projection of subopercle, make the new species easily distinguishable from congeners. This is the second representative of the C. hubbsi group in the western Indian Ocean in addition to the previously known C. melanosagmatus.

Numerical simulation of forced convection heat transfer mechanism and comprehensive performance on hydrophobic structure surface

The numerical simulation of the hydrophobic structured surfaces is conducted in this work to investigate the confined effects of heat transfer performance and forced convection resistance. A new heat transfer model of air cavities is established based on the cavitation heat transfer process. Four structures (i.e., longitudinal ridges, square posts, square holes and transverse ridges) are constructed to study the effect of air cavities and slip-velocity on heat transfer. The goodness factor φ is utilized to evaluate the overall performance of the hydrophobic structured surfaces with different geometries. The results show that the existence of air cavities produces a negative effect of heat transfer, and the slip-velocity can enhance heat transfer performance. However, the coupling effect of air cavities and slip-velocity is related to surface structure rather than linear superposition. In addition, the heat transfer performance and frictional resistance, as well as goodness factor are dependent on the structure and contact angle of hydrophobic surface. Compared with the smooth surface, the hydrophobic surfaces for all structures exhibit a better goodness factor, and the maximum φ/φ0 of 1.105 can be achieved on the square posts structure.

A transient apical extracellular matrix relays cytoskeletal patterns to shape permanent acellular ridges on the surface of adult C. elegans.

Epithelial cells secrete apical extracellular matrices to form protruding structures such as denticles, ridges, scales, or teeth. The mechanisms that shape these structures remain poorly understood. Here, we show how the actin cytoskeleton and a provisional matrix work together to sculpt acellular longitudinal alae ridges in the cuticle of adult C. elegans. Transient assembly of longitudinal actomyosin filaments in the underlying lateral epidermis accompanies deposition of the provisional matrix at the earliest stages of alae formation. Actin is required to pattern the provisional matrix into longitudinal bands that are initially offset from the pattern of longitudinal actin filaments. These bands appear ultrastructurally as alternating regions of adhesion and separation within laminated provisional matrix layers. The provisional matrix is required to establish these demarcated zones of adhesion and separation, which ultimately give rise to alae ridges and their intervening valleys, respectively. Provisional matrix proteins shape the alae ridges and valleys but are not present within the final structure. We propose a morphogenetic mechanism wherein cortical actin patterns are relayed to the laminated provisional matrix to set up distinct zones of matrix layer separation and accretion that shape a permanent and acellular matrix structure.

Ichthyoliths of the Corumbataí Formation: new occurrences and interpretations for São Paulo state, Brazil (northeastern Paraná basin)

The Permian ichthyofauna of the Passa Dois Group is well known for the ubiquitous presence of disarticulated elements of a variety of fish taxa that remains largely understudied. Lower actinopterygians (Palaeonisciformes) are the most abundant, together with isolated teeth of Xenacanthiformes chondrichthians. This study brings new information on the external micro-ornamentations of actinopterygian teeth and rhomboid scales of the Corumbataí Formation collected for the first time in Santa Rosa de Viterbo region in the State of São Paulo, as well as a new proposition to approach this remains by using cluster analysis. These fossils were found in distal storm deposits (tempestite) and were separated from the rock matrix for analysis. Six distinct actinopterygian tooth morphotypes were identified. Curved forms are dominant in the assemblage, with ornamentations varying from smooth to ribbed shafts and others with grooves and tubercles. The scales are very fragmented showing surface micro-punctuations and longitudinal ridges. The Xenacanthiformes tricuspid teeth were very scarce in the assemblage and no complete specimen was recovered. Nonetheless, it was possible to identify them by their subtriangular shape and drop-shaped basal tubercle. Both ichthyodonts and scales show characteristics similar to at least other 26 occurrences, spread over more than 1000 km, and already described in the literature stratigraphically positioned above and below the Corumbataí Formation, attesting the wide temporal and spatial distribution of these fossils.

First record of biofluorescence in lumpfish (Cyclopterus lumpus), a commercially farmed cleaner fish.

This study is the first known observation of biofluorescence in the lumpfish (Cyclopterus lumpus). Individual lumpfish were illuminated with blue excitation lighting for photography with both hyperspectral and filtered multispectral cameras. All photographed juvenile lumpfish (n=11) exhibited green biofluorescence. Light emissions were characterised with two peaks observed at 545 and 613 nm, with the greatest intensity along the tubercles of the high crest and the three longitudinal ridges. Further research on the dynamics of biofluorescence through the lifecycle of this species is required.

Early development of the human embryonic testis

Human gonadal development culminating in testicular differentiation is described through analysis of histologic sections derived from 33-day to 20-week human embryos/fetuses, focusing on early development (4–8 weeks of gestation). Our study updates the comprehensive studies of Felix (1912), van Wagenen and Simpson (1965), and Juric-Lekic et al. (2013), which were published in books and thus are unsearchable via PubMed. Human gonads develop from the germinal ridge, a thickening of coelomic epithelium on the medial side of the urogenital ridge. The bilateral urogenital ridges contain elements of the mesonephric kidney, namely the mesonephric duct, mesonephric tubules, and mesonephric glomeruli. The germinal ridge, into which primordial germ cells migrate, is initially recognized as a thickening of coelomic epithelium on the urogenital ridge late in the 4th week of gestation. Subsequently, in the 5th week of gestation, a dense mesenchyme develops sub-adjacent to the epithelium of the germinal ridge, and together these elements bulge into the coelomic cavity forming bilateral longitudinal ridges attached to the urogenital ridges. During development, primordial cells migrate into the germinal ridge and subsequently into testicular cords that form within the featureless dense mesenchyme of the germinal ridge at 6–8 weeks of gestation. The initial low density of testicular cords seen at 8 weeks remodels into a dense array of testicular cords surrounded by α-actin-positive myoid cells during the second trimester. Human testicular development shares many features with that of mice being derived from 4 elements: coelomic epithelium, sub-adjacent mesenchyme, primordial germ cells, and the mesonephros.

Morphological ontogeny of Platynothrus coulsoni sp. nov. (Acari, Oribatida, Camisiidae) from Spitsbergen (Norway)

The morphological ontogeny of Platynothrus coulsoni sp. nov. is described and illustrated. This species is the most similar to P. quadristriatus Hammer, 1958 as adult, but differs from it mainly by having more longitudinal ridges on the notogaster and fewer genital setae. Most prodorsal and gastronotal setae of the larva of P. coulsoni are of medium size and smooth, except for barbed h1, and in the nymphs these setae are relatively short. In all instars, one pair of hypostomal setae m is present, and palp femur has one seta. The setation of leg setae of P. coulsoni is generally similar to that of P. punctatus (L. Koch, 1879), but differs from it mainly by having more setae on tarsi I–III of deutonymph and tritonymph, and all tarsi of adult.

Study on the Characteristics of Soil Erosion in the Black Soil Area of Northeast China under Natural Rainfall Conditions: The Case of Sunjiagou Small Watershed

In the black soil area, where soil erosion is severe and the soil is in urgent need of ecological restoration, providing reasonable and practical measures to prevent soil erosion and restore the soil is an urgent issue at present. In this study, nine runoff plots were deployed in Bin County, the core area of soil erosion control, to monitor runoff and soil loss long-term, simulated by the erosion potential method (EPM) for comparison. Studies have shown that soil erosion is strongly influenced by soil conservation measures, land use, and vegetation cover. In contrast, slope, pre-soil moisture content, and soil crusting due to rainfall can affect erosion in a single rainfall event. The most severe soil erosion was in bare land, up to 1093.58 t km−2 a−1, followed by longitudinal ridge tillage land (751.88 t km−2 a−1) and cross ridge tillage land (31.58 t km−2 a−1). The shrublands and mixed forests planted for ecological restoration experienced almost no erosion. The soil loss rate of the cross ridge tillage and ecological restoration plots was much lower than the allowable soil loss rate (200 t km−2 a−1). Under erosive storms, longitudinal ridge tillage can produce soil loss rates that far exceed those of bare ground. The change from longitudinal ridge tillage to cross ridge tillage on gentle slopes can effectively prevent soil erosion in the study area. The vegetation restoration measures of planting shrubs such as Amorpha fruticosa Linn. are incredibly effective in the ecological restoration of wastelands in black soil areas. For the black soil area after the retreat, the vertical structure of vegetation can be improved by planting shrubs at the bottom, thus achieving a good restoration effect.

An enigmatic large mawsoniid coelacanth (Sarcopterygii, Actinistia) from the Upper Jurassic Kimmeridge Clay Formation of England

ABSTRACT A large mawsoniid coelacanth from the lower part of the marine Kimmeridge Clay Formation of England (Kimmeridgian, Upper Jurassic) is studied here. The material is constituted by a group of bones from the head and shoulder girdle of a considerably large individual (estimated length ca. 1.5 m), including the left angular, left dentary, left prearticular, left palatoquadrate complex, both ceratohyals and right cleithrum. Characters such as the coarse external ornamentation of the angular, and the robustness of the quadrate and the cleithrum allow classification of the individual as a member of the Mawsoniidae; whereas the configuration of external bones of the lower jaw (ornamentation of the angular constituted mainly by longitudinal ridges, the presence of a lateral swelling in the dentary) indicates stronger Gondwanan affinities than previously expected (i.e., with the genus Mawsonia, up to now only recorded in South America by the end of the Jurassic). Considering the above, two alternative evolutionary, paleobiogeographic, and taxonomic scenarios are discussed: (1) the new individual can be referred to the European mawsoniid genus Trachymetopon (Lower–Middle Jurassic), in which case it should be assumed this genus reached the Upper Jurassic, and with a morphological variability higher than previously suspected (including some characters previously assumed as diagnostic for Mawsonia). Or (2) an unknown Mawsonia-like form was present in the Upper Jurassic of Europe. The last scenario puts the identification of isolated elements of European Jurassic giant mawsoniids in a new complex taxonomic and paleobiogeographic context, which will deserve further research.

Two New Species-Groups Defined in Lycocerus Gorham (Coleoptera: Cantharidae), with a Preliminary Investigation on Their Phylogenetic Positions

Two new species-groups of Lycocerus Gorham are defined, L. kuatunensis group and L. continuatus group, which could be differentiated from all others except L. canthariformis (Ishida, 1986) by the aedeagus with conjoint dorsal plates of parameres. The L. kuatunensis group is composed of five species, including L. kuatunensis (Wittmer, 1995), L. svihlai (Wittmer, 1995) comb. nov., L. nigroapicis Y. Yang et X. Yang, 2013, L. bifurcatus Y. Yang et X. Yang, 2013, and L. nigrigenus Y. Yang et X. Yang, 2013, and the L. continuatus group consists of two species, L. continuatus sp. nov. and L. parameratus Y. Yang et X. Yang, 2013. These two groups differ from each other in the aedeagus possessing longitudinal ridges on inner surface of conjoint dorsal plates of parameres or not, laterophyses compressed or slender, accessory gland uniformly thin or slightly enlarged apically. A morphological phylogenetic analysis shows that the two new groups are closer to the L. canthariformis subgroup of the L. vitellinus group due to the similarity in their aedeagi. The above species are provided with habitus photos, aedeagi, reproductive systems and abdominal sternites VIII of female. A key to the species and a distribution map are provided.

Linearised Reynolds-averaged predictions of secondary currents in turbulent channels with topographic heterogeneity

A rapid predictive tool based on the linearised Reynolds-averaged Navier–Stokes equations is proposed in this work to investigate secondary currents generated by streamwise-independent surface topography modulations in turbulent channel flow. The tool is derived by coupling the Reynolds-averaged momentum equation to the Spalart–Allmaras transport equation for the turbulent eddy viscosity, using a nonlinear constitutive relation for the Reynolds stresses to capture correctly secondary motions. Linearised equations, describing the steady flow response to arbitrary surface modulations, are derived by assuming that surface modulations are shallow. Since the equations are linear, the superposition principle holds and the flow response induced by an arbitrary modulation can be obtained by combining appropriately the elementary responses obtained over sinusoidal modulations at multiple spanwise length scales. The tool permits a rapid exploration of large parameter spaces characterising structured surface topographies previously examined in the literature. Here, channels with sinusoidal walls and with longitudinal rectangular ridges are considered. For sinusoidal walls, a large response is observed at two spanwise wavelengths scaling in inner and outer units respectively, mirroring the amplification mechanisms in turbulent shear flows observed from transient growth analysis. For longitudinal rectangular ridges, the model suggests that the analysis of the response and the interpretation of the topology of secondary structures is facilitated when the ridge width and the gap between ridges are used instead of other combinations proposed in the literature.

Two new freshwater species of Surirella (Bacillariophyta) from the Wuling Mountains, China.

Two sympatric Surirella species found at the same specific locality in the Wuling Mountains of China are documented with light and scanning electron microscope. Both species are new to science and named S.wufluminensis sp. nov. and S.suiningensis sp. nov. Surirellawufluminensis has large frustules that are either clockwise or counterclockwise twisted when viewed with the light microscope, and possesses distinctive fibulae, mound-like outgrowths on the valve surface throughout, raised longitudinal ridges on both sides of the raphe, and two helictoglossa-like processes at one apex internally. Surirellasuiningensis has narrowly ovate valve outline, distinctive fibulae, troughs alternating with crests from pole to pole, and two helictoglossa-like processes at one apex internally. These two species do not produce costae on the valve surface in contrast to many species in Surirella. This study provides a further two examples of the wide range of morphological diversity in the genus Surirella.

The morphology and sedimentology of the Walai rock avalanche in southern China, with implications for confined rock avalanches

The Walai rock avalanche (H/L ratio = 0.32), which was laterally and frontally confined occurred in the high mountainous areas of the eastern Tibetan Plateau. According to the field investigation and optically stimulated dating, the initial rock slope failure was determined to be a wedge failure controlled by bedding and two joint sets at approximately 38 ka ago. Based on the topography reconstruction, the deposited volume of this rock avalanche was estimated at 5.2 × 107m3, which was 1.24 times the mass detached from the source area. We observed and mapped trimlines, longitudinal ridges, arched ridges, and lateral ridges associated with the rock avalanche. We also observed well-developed sedimentary features, including carapace facies, body facies, stratified structures, jigsaw fractures, directional arrangements, shear-damaged rock clasts, and interior folds. Measured grain size distributions indicated that the Walai rock avalanche fragmented within a relatively short travel distance after detachment from the source area, with no progressive reduction of grain sizes during the subsequent movement. Based on the morphological and sedimentary features, the emplacement process of the Walai rock avalanche was determined to be controlled by the local terrain and could be divided into four stages: an initiation stage (detachment), an accelerating stage (fragmentation), a longitudinal compression stage (momentum transfer), and a spreading stage (shearing).

A new Leptobrachella species (Anura, Megophryidae) from South China, with comments on the taxonomic status of L. chishuiensis and L. purpurus

A new species of Leaf Litter Toad,Leptobrachella shimentainasp. nov., is described from the Shimentai and Luokeng nature reserves of northern Guangdong Province, southern China. The new taxon can be distinguished from all recognized congeners by a combination of discrete morphological character state differences relating to its small body size (SVL 26.4–28.9 mm in six adult males, 30.1 and 30.7 mm in two adult females); a number of apparently fixed color pattern character differences (including eye coloration and color pattern features from dorsal, ventral, and dorsolateral surfaces of its head, body, limbs, and ventrum); the morphological and discrete characteristics of the external phenotype (the skin texture of dorsum and ventrum, the presence of supra-axillary and ventrolateral glands, the wide dermal fringes and rudimentary webbing on toes, and the uninterrupted longitudinal ridges under toes). Two samples of this new species previously were proposed as representing a new, unnamed species. We now substantiate this claim by providing diagnostic comparisons of discrete character differences. In addition, we also discuss taxonomic uncertainty surrounding the identity of two congeners,L. chishuiensisandL. purpurus, which we interpret as indicative of taxonomic inflation in the species-rich subfamily Megophryidae.

Fecundity and morphological description of the eggs of Psorophora cyanescens (Coquillett, 1902) (Diptera: Culicidae) by scanning electron microscopy

Taxonomic studies on mosquitoes are based on the morphological description of larvae and adults. However, few studies have focused on the morphological description of eggs despite their taxonomic value. The description of mosquito eggs by scanning electron microscopy (SEM) allows more detailed descriptions of the ornamentation of the egg, which can provide diagnostic characters of the species. The objective of the work was to describe the eggs of Psorophora cyanescens by SEM and provide fecundity data for the species. In general, Ps. cyanescens eggs are elliptical and very wide. The exochorion is characterized by polygon pattern, where each polygon consists of longitudinal ridges joined by cross-ridges defining regular "hexagonal" areas. Each longitudinal ridge consisting by a small tubercle. The small tubercles are irregular, rectangular, rounded, or tubular. The ornamentation of the exochorion also has long and conical tubercles throughout the egg region. The micropylar apparatus located in the anterior region of the egg has a prominent, continuous and thickness collar. Psorophora cyanescens laid mature eggs at 2.5 days post-feeding. The mean number of eggs per female was 82.20 (± 13.31). This is the first study that describes the ultrastructure of the morphology of the eggs of Ps. cyanescens by SEM. With the contribution of the present work, there are five species of the genus Psorophora whose eggs morphology is described by SEM: Ps. albigenu, Ps. albipes, Ps. columbiae, Ps. cyanescens, and Ps. ferox.