Spiracular Plate Research Articles

The Genus Hyalomma: VII. Redescription of all Parasitic Stages of H. (Euhyalomma) dromedarii and H. (E.) schulzei (Acari: Ixodidae)

The ticks, Hyalomma (Euhyalomma) dromedarii and Hyalomma (Euhyalomma) schulzei , are considered to be the species most closely associated with camels. H. dromedarii can behave as a three-, two-, or one-host species, with the two-host life cycle seemingly most common. Camels are the main hosts of the adults, which also parasitize other domestic animals. Nymphs and larvae can use the same hosts, especially camels, as the adults, but can also parasitize rodents, leporids, hedgehogs, and birds. H. dromedarii is widely distributed in North Africa, the northern regions of West, Central, and East Africa, Arabia, Asia Minor, the Middle East, and Central and South Asia. H. schulzei is a two-host species. Camels are the principal hosts of the adults, with some records from cattle and goats, whereas the immature stages infest hares, burrowing rodents, and hedgehogs. H. schulzei has a more limited geographic distribution in Asia and Egypt than H. dromedarii, and with the exception of southeastern Iran, it is a fairly uncommon tick. Among other features that are fairly similar, males of H. dromedarii can be distinguished from those of H. schulzei by a narrow, subtriangular parma, usually very large subanal shields, and a long dorsal prolongation of the spiracular plates. Males of H. schulzei have a broad and rectangular parma, paramedian festoons that protrude posteriorly, smaller subanal shields, and a very short dorsal prolongation of the spiracular plates. The females of H. dromedarii can be distinguished from those of H. schulzei by a narrow V-shaped genital aperture compared with a very wide, deep, U-shaped genital aperture. Here all the parasitic stages of both species are illustrated and redescribed, and characteristics that distinguish the adults from those of other closely related species are supplied. Data on their hosts, geographic distribution and disease relationships are also provided.

The Genus <I>Hyalomma</I>: VII. Redescription of all Parasitic Stages of <I>H</I>. (<I>Euhyalomma</I>) <I>dromedarii</I> and <I>H</I>. (<I>E</I>.) <I>schulzei</I> (Acari: Ixodidae)

The ticks, Hyalomma (Euhyalomma) dromedarii Koch, 1844 and Hyalomma (Euhyalomma) schulzei Olenev, 1931, are considered to be the species most closely associated with camels. H. dromedarii can behave as a three-, two-, or one-host species, with the two-host life cycle seemingly most common. Camels are the main hosts of the adults, which also parasitize other domestic animals. Nymphs and larvae can use the same hosts, especially camels, as the adults, but can also parasitize rodents, leporids, hedgehogs, and birds. H. dromedarii is widely distributed in North Africa, the northern regions of West, Central, and East Africa, Arabia, Asia Minor, the Middle East, and Central and South Asia. H. schulzei is a two-host species. Camels are the principal hosts of the adults, with some records from cattle and goats, whereas the immature stages infest hares, burrowing rodents, and hedgehogs. H. schulzei has a more limited geographic distribution in Asia and Egypt than H. dromedarii, and with the exception of southeastern Iran, it is a fairly uncommon tick. Among other features that are fairly similar, males of H. dromedarii can be distinguished from those of H. schulzei by a narrow, subtriangular parma, usually very large subanal shields, and a long dorsal prolongation of the spiracular plates. Males of H. schulzei have a broad and rectangular parma, paramedian festoons that protrude posteriorly, smaller subanal shields, and a very short dorsal prolongation of the spiracular plates. The females of H. dromedarii can be distinguished from those of H. schulzei by a narrow V-shaped genital aperture compared with a very wide, deep, U-shaped genital aperture. Here all the parasitic stages of both species are illustrated and redescribed, and characteristics that distinguish the adults from those of other closely related species are supplied. Data on their hosts, geographic distribution and disease relationships are also provided.

New Reports of Antricola guglielmonei and Antricola delacruzi in Brazil, and a Description of a New Argasid Species (Acari)

Adults of 3 tick species (Acari: Argasidae) identified as Antricola guglielmonei, Antricola delacruzi, and Carios rondoniensis n. sp. were collected on bat guano in a cave in the state of Rondônia, western Amazon, Brazil. Adults of C. rondoniensis possess a unique combination of characters that distinguish them from all described adults in the Argasidae, i.e., a large spiracular plate densely filled with small goblets, a well-developed flap covering the female genital opening, and palpi containing several tufts of long setae on articles 2 and 3. Unlike Ornithodoros or other Carios species, adults of C. rondoniensis have a scooplike hypostome devoid of denticles, as in Antricola spp. Conversely, the presence of a pair of long posthypostomal setae, and a slitlike transverse fissure at the capsule opening of the Haller's organ, are characters of C. rondonensis that are also found in species of Carios and Ornithodoros, but not in Antricola species. Molecular analyses inferred from a portion of the 16S rRNA mitochondrial gene indicate that C. rondoniensis is phylogenetically closest to species of Carios, followed by species of Antricola, and then Ornithodoros. Because the highest bootstrap value linking C. rondoniensis to Carios spp. was 62%, further phylogenetic studies are needed to better evaluate the taxonomic status of the former species.

Cuterebrosis in a Florida Horse: First Equid Record for North America

Larvae of Cuterebra spp. (Diptera: Oestridae) typically infest mice, rats, chipmunks, rabbits, hares, and certain other rodents or lagomorphs native to the Americas (Sabrosky 1986). However, non-native members of these orders, as well as mammals in other orders such as artiodactyls (e.g., deer and pigs), carnivores (raccoons, domes tic cats and dogs, etc.), and primates (humans), can be parasitized by these bot flies (Hall 1925; Sabrosky 1986; Baird et al. 1989; Glass et al. 1998; Harris et al. 2000; Suedmeyer et al. 2000; Safdar et al. 2003; Slansky & Huckabee 2006; Slansky 2007a). Infestation of these atypical or accidental hosts, an affliction termed cuterebrosis or cuterebriasis, occurs when they contact first in stars of Cuterebra spp. newly hatched from eggs oviposited in the habitats of the typical hosts (Catts 1982; Slansky & Kenyon 2003). Published cases of cuterebrosis in perissodac tyls (donkeys, horses, zebras, etc.) are few and mostly unsubstantiated. Knipling & Bruce (1937) reported that a second instar of Cuterebra buc cata (Fabricius), a lagomorph-infesting species, was removed from a mule in South Carolina (16 VII-1935), but they provided no justification for this species assignment. Second instar Cuterebra spp. are very difficult to identify visually to spe cies (even currently) and there were no descrip tions of second instars of other Cuterebra spp. for comparison at the time of Knipling & Bruee's (1937) report. Thus, I consider the assignment of C. buccata for their specimen as unsubstantiated. Dalmat (1942) indicated that asses (donkeys) were atypical hosts o? Cuterebra spp., but no de tails were given. Similarly, Sabrosky (1986) men tioned mules as atypical hosts of these bot flies, but supportive information was not provided. During curation of the immature insect collec tion in the Department of Entomology & Nema tology at the University of Florida, an isopro panol-preserved larva that appeared to belong to a Cuterebra species was encountered. This speci men had been collected from beneath the hide of a horse in Marion Co., Florida (ll-VII-1991). This specimen possesses characteristics typical of a third instar Cuterebra spp., including dark brown cuticular platelets covering its body (Fig. la), 2 pair of sensory tubercles and 2 sharply pointed mouth hooks on its head (Fig. lb) and on its anal segment (Fig. lc), 2 kidney-shaped spiracular plates, each containing 3 wedge-shaped sections with serpentine spiracular slits (Fig. lc inset). The larva is coated with a substantial amount of white material, which most likely is purulent matter from the host, as is often seen when these larvae infest atypical hosts (Slansky 2007b). The species o? Cuterebra that this specimen be longs to is unclear, as there are no taxonomic keys for species identification of larvae in this genus. However, the platelets covering its exterior either are ovoid, have blunt, single tips, or are multi pointed, indicating this is a larva of a rodent-in festing Cuterebra species rather than that of a lagomorph-infesting species, third instars of which lack flattened, multipoint platelets and have many single-pointed, spine-like platelets (Knipling & Brody 1940; Dalmat 1942; Bennett 1955; Haas & Dicke 1958; Baird & Graham 1973; Slansky 2007a). There are three rodent-infesting species of Cuterebra in Florida: C. americana (Fabricius) (its main typical hosts are Neotoma woodrats), C. fontinella (Clark) (Peromyscus mice) and C. emasculator Fitch (Sciurus squirrels) (Slansky 2006). Cuticular platelet patterns are available only for the latter two species (Bennett 1955; Slansky & Huckabee 2006), and of these, this specimen more closely resembles C. fonti nella (F.S., unpublished observations). However, determining the species of this specimen must await a morphological description of the third in star of C. americana, knowledge of intraspecific variation in morphological characteristics of these larvae (see Slansky & Huckabee, 2006), and/or molecular analyses (Otranto et al. 2003; Noel et al. 2004) of the candidate species. This appears to be the first record for Florida of cuterebrosis in a horse or other perissodactyl, and the first such record for a horse in North America. Based on the scarcity of published reports, infes tation of these animals by larvae o? Cuterebra ap pears to be a very rare phenomenon that should pose little concern to horse owners. This contrasts with the common occurrence of larvae oiGastero philus spp. bot flies, which use horses and other perissodactyls as typical hosts and can require treatment to avoid pathological effects (Wall & Shearer 1997; Catts & Mullen 2002). One might expect that these animals would be exposed to Cuterebra spp. larvae both while grazing, espe cially lagomorph-infesting species that likely ovi posit in grassy areas (e.g., Suedmeyer et al. 2000), and in their stalls, especially rodent-infesting species that may inhabit barns (F. S., unpublished observations). Thus, the rarity of published re ports of cuterebrosis in perissodactyls may indi cate that these atypical hosts exhibit resistance to

Three new species of Antricola (Acari: Argasidae) from Brazil, with a key to the known species in the genus.

Three new species of Antricola (Acari: Argasidae) are described from adult specimens collected on bat guano in different caves in Brazil. The female of Antricola guglielmonei n. sp. is easily determined by the presence of 2 smooth, depressed areas lacking setae in the posterolateral portions of the dorsum of the idiosoma, together with the partial fusion of the tubercles in the anteromedian portion of the idiosoma. The male of this species has a small spiracular plate surrounded by a pattern of tubercles disposed concentrically in its dorsal portion. Both sexes have cervical grooves very slightly marked. Antricola delacruzi n. sp. represents the only Antricola species with the dorsum of the idiosoma devoid of tubercles in both sexes and with scarce and minute setae placed over the smooth cuticle. The female of A. inexpectata n. sp. is known only from a few specimens. In this species, lines of smooth cuticle lacking setae separate the tubercles of the dorsum. In addition, there are 3 clumps of plumose setae close to the spiracular plate, in the ventrolateral portions of the idiosoma, in 3 well-delimited regions over cuticular thickenings. These 3 species share the peculiarity of a Haller's organ with the anterior pit bearing only 7 + 2 setae. The collection of these new species in Brazilian caves greatly expands the known range of the genus. A key to the adults of all known species of the genus is provided.

Scanning electron microscopic study of third-instar warbles in yak in China

Scanning electron microscopic observations were performed to compare the structures of third-instar of three species of warbles ( Hypoderma bovis, H. lineatum and H. sinense) that infest yak in China. The heads of the warbles consisted of mouths and opercular sutures with spinal bands between them. We could not detect any morphological differences in the shape of the warble’s heads among these three species. The spiracular plate of H. bovis was strongly concaved and had numerous spines at the spiracular opening rims. The H. lineatum had flat spiracular plates and no spines on the spiracular plates. In the case of H. sinense the spiracular plate was as flat as that of H. lineatum but had small sized and fewer spines on the spiracular plates. At the ventral side on the tenth segment of the warble body of H. bovis the spinal band was absent. Although H. lineatum had only one band at the posterior border on the tenth ventral segment, H. sinense had two bands of spines at the anterior and posterior border on the tenth segment.

Species identification of Hypoderma affecting domestic and wild ruminants by morphological and molecular characterization.

Cuticular structures and the sequence of the cytochrome oxidase I gene were compared for Hypoderma bovis (Linnaeus), Hypoderma lineatum (De Villers), Hypoderma actaeon Brauer, Hypoderma diana Brauer and Hypoderma tarandi (Linnaeus) (Diptera, Oestridae). Third-stage larvae of each species were examined by scanning electron microscopy revealing differences among species in the pattern and morphology of spines on the cephalic and thoracic segments, by spine patterns on the tenth abdominal segment, and by morphology of the spiracular plates. The morphological approach was supported by the molecular characterization of the most variable region of the cytochrome oxidase I (COI) gene of these species, which was amplified by polymerase chain reaction and analysed. Amplicons were digested with the unique restriction enzyme, BfaI, providing diagnostic profiles able to simultaneously differentiate all Hypoderma species examined. These findings confirm the utility of morphological characters for differentiating the most common Hypoderma larvae and reconfirm the power of the COI gene for studying insect identification and systematics.

Taxonomic status of Ixodes didelphidis (Acari: Ixodidae).

Ixodes didelphilis Fonseca & Aragão was described in Brazil in 1952 as a new tick species that differed from Ixodes loricatus Neumann by the spiracular plate pattern. We have reared four tick colonies from different geographic areas in the laboratory that were started from single engorged females originally identified as I. didelphidis (BMG, colony ) and I. Iocicatus (CSP, PSP, and TRJ colonies). We analyzed the spiracular plate morphology of F1 adult ticks from each tick colony, compared their biological 11th, and performed a molecular analysis of the second internal transcribed rDNA spacer (ITS2) to test the validity of the species I. didelphidis. The spiracular plate analysis of laboratory F1 adult ticks yielded single females from the four colonies showed variations that invalidate morphological parameters for differentiation of loricatus and I. didelphidis. Biological data of the BMC, CSP, and TRJ colonies were similar. The biology ofthe PSP colony was not evaluated. The ITS2 sequence variations observed between the tick colonies ranged from 1.3 to 4.9%, and the similarity tree constructed by the neighbor-joining method with nucleotide distances showerl that the distances between the samples were similar to what is expected for intraspecific variations found in other ticks species. The morphological and biological results, in conjunction with the ITS2 analysis, supported the conspecificity I. loricatus and I. didelphidis.

Abnormal development of Rhipicephalus sanguineus (Ixodidae).

Three malformed Rhipicephalus sanguineus specimens were noticed in a tick laboratory colony. These specimens had different degrees of twining, from an almost fused individual (with two anal pores) to a partially fused adult male, with four spiracular plates. One female was a heart-shaped specimen. with both body halves fused along a longitudinal axes, with four spiracular plates and two anal pores.

Scanning electron microscopy of the second-instar larva of Gasterophilus nasalis.

The second-instar larva of the bot fly Gasterophilus nasalis (L.) (Diptera: Gasterophilidae) is described for the first time, based on scanning electron microscope (SEM) studies. On the pseudocephalum the larva bears an antenomaxillary sensory complex formed by the antenna (coeloconic sensilla) and the maxillary palp with a set of six coeloconic sensilla and four basiconica sensilla. The oral opening is latero-posteriorly limited by small spines, and exhibits strongly ornamented maxillae and mandibles. The thoracic and abdominal segments are circled by two bands, each with two rows (except the last segment that has one row) of backwardly pointed spines, and have cuticular depressions. Trichoid and campaniform sensilla surround the larval segments. The anterior spiracular opening is a small aperture. The terminal end of the eighth abdominal segment shows a spiracular cavity, lateral tubercles, eight basiconic and two trichoid sensilla. Each spiracular plate has two slightly curved slits, each with a serrated rima. There is a probable ecdysial scar. The findings of this ultrastructural study are compared with those other of larval flies.

Morphology of the second- and third-instar larvae of Dermatobia hominis by scanning electron microscopy.

Larvae of Dermatobia hominis 10-27 days old were collected from experimentally infected rats and their morphology was studied by scanning electron microscopy. The moult from the second to third instar occurs at 18 days, with emergence from the host at 30 days post-infection. The second-instar larvae bear on the pseudocephalon, antennae (coeloconic sensilla), and coeloconic and basicoconic sensilla on the maxillary sensory complex. The thoracic segments bear small backwardly-directed spines anteriorly and ventral trichoid and campaniform sensilla. The first four abdominal segments have small and large backwardly-directed spines that are absent on segments five and six. The seventh and eighth abdominal segments have medium-sized forwardly-directed spines. Abdominal segments are encircled by campaniform sensilla. The terminal end of the eighth abdominal segment bears the anus, prominent anal lobes and two spiracular openings on each spiracular plate. Spiracular plates show a radial sun ray pattern. The rear abdomen also bears an ecdysal aperture, several pores and eight coeloconic sensilla. Although there are slight morphological differences, the spines (predominantly flat and thorn-like) and sensilla (campaniform and coeloconic) of the third-instar larvae show a similar arrangement to that of second-instar larvae. Thoracic trichoid sensilla are not seen in third-instar larvae. A perispiracular gland aperture is situated above each posterior spiracular opening. These morphological features are compared with those of other cuterebrid larvae.

Comparative scanning electron microscopy of third-instar Hypoderma spp. (Diptera: Oestridae).

Scanning electron microscope study of third-instar larvae of four species of Hypoderma revealed differences among species in the pattern of spination, spine morphology and morphology of the spiracular plates. These observations identify characters that enable the differentiation of Hypoderma actaeon and H. diana, parasitizing red deer (Cervus elaphus) in Europe, and provide additional characters for differentiating H. bovis and H. lineatum parasitizing cattle.

Morphological study of the larval spiracular system in eight Lutzomyia species (Diptera: Psychodidae).

The morphology of the spiracles of fourth instar larva in eight sandfly species were examined by light and scanning electron microscopy. Species studied were: Lutzomyia longipalpis (Lutz & Neiva), L. ovallesi (Ortiz), L. youngi Feliciangeli & Murillo, L. evansi (Nuñez-Tovar), L. trinidadensis (Newstead), L. migonei (França), L. absonodonta Feliciangeli, and L. venezuelensis (Floch & Abonnenc). In larvae of all eight species both thoracic and abdominal spiracles are located at the top of a globular bulge. Their structure consists of a spiracular plate with a sclerotized central portion and a rose-like peripheral portion. The latter has circularly arranged papillae, separated from each other by elongated septa. Each papilla is longitudinally crossed by a fine cleft dividing it into two identical parts. The taxonomic and adaptative value of spiracular morphology is discussed.

The question of fluctuating asymmetry in the blacklegged tick Ixodes scapularis (Acari: Ixodidae).

An analysis of fluctuating asymmetry was conducted on populations of the blacklegged tick Ixodes scapularis. The eight groups used in this study consisted of larvae and nymphs and males and females from the states of Minnesota, Massachusetts, Maryland, Missouri, North Carolina and Georgia and the F1 progenies of reciprocal crosses between ticks from Massachusetts and Georgia. Measurements included 16 larval, 19 nymphal, ten female and 12 male bilateral characters. Only five differences between the right and left bilateral characters had normal distributions with means of zero and differences in variances between the groups. These five characters included three setal lengths of the larvae, the spiracular plate length of females and the coxa I internal spur widths of males. Bivariate plots of character size ((R + L)/2) and asymmetry (R-L) showed no correlation. In the spiracular plate lengths of females and one of the setal lengths, ticks from Massachusetts had significantly less within-group variance than all the other groups. The only character in which fluctuating asymmetry was observed was the coxa I internal spur width of males, in which ticks from Minnesota, Missouri and North Carolina had significantly greater variance than the remaining groups; fluctuating asymmetry in this character may be explained by sexual selection. The cross progeny did not demonstrate any fluctuating asymmetry, as would be expected if the northern and southern forms of I. scapularis were true species. The virtual lack of fluctuating asymmetry in the characters used in this study further supports the conclusions of other studies which concluded that I. scapularis is a species with clinical variation and a broad geographic distribution.

Scanning electron microscopy studies on the first-instar larva of Dermatobia hominis.

First-instar larvae of Dermatobia hominis collected 1, 4 and 7 days after having penetrated experimentally infected rats, were studied by scanning electron microscope (SEM) observation. On the pseudocephalon there are basiconic and trichoid sensilla (antennal sensory complex), and basiconic, coeloconic and campaniform sensilla (maxillary sensory complex). The thoracic segments bear several rows of small, backwardly pointed, spines, and trichoid, campaniform, coeloconic and pit sensilla. The anterior spiracle is a minute opening. Both small and large spines directed posteriorly are on the first to fourth abdominal segments, which also bear coeloconic and companiform sensilla. These sensilla are present on the unarmed (fifth and sixth) and armed (seventh) abdominal segments. The seventh and the last (eight) abdominal segments have forwardly directed spines. Each spiracular plate has two spiracular openings and four spatulate-like structures called sun rays. The anus and the coeloconic sensilla are proeminent on the last segment. The results are compared with other parasitic dipteran larvae, and emphasize that the multiple types of sensilla on D.hominis larva may have importance in establishing the parasitic phase of the life cycle of this insect.

Spiracular Plate of Nymphal and Adult Hard Ticks (Acarina: Ixodidae): Morphology and Cuticular Ultrastructure

Morphology and ultrastructure of the nymphal and adult spiracular plate of five species of hard ticks (Ixodidae) are described using scanning scanning and transmission electron microscopy. Both the surface area and the number of aeropyles increase significantly between the nymphal and adult stages and are greater in females than in males. The spiracular plate is divided into four regions: an outer cuticle with aeropyles, a labyrinth composed of cuticular pedicels and chambers, a thick basal plate, and a cellular layer. The pedicels that separate the chambers of the spiracular plate have a large central channel, surrounded by smaller secondary channels. These channels are found throughout the basal plate cuticle and contain a granular substance, probably secreted by the epidermal cells. The basal plate gland is enclosed by the cuticle of the basal plate and is dispersed randomly in the basal plate. This gland has duct and secretory cells, and the duct has a valve-like portion at its apical end where the gland opens at the base of a chamber. The basal plate gland cells and epidermal cells beneath the basal plate contain many free ribosomes, lipid droplets, rough endoplasmic reticulum, and mitochondria. The glands may be involved in the regulation of water loss and air diffusion. Additional key words: water regulation, gas exchange, glandular cells Ticks are generally rather impervious to desiccation because of their thick cuticle and very few sites from which water may be lost to the external environment, such as the mouth, anus, genital opening, and spiracles (Knulle & Rudolph 1982; Sauer & Hair 1986). The spiracles regulate gas exchange and limit water loss from the respiratory system into surrounding environment (Pugh et al. 1988, 1990). Spiracles of Ixodida are located near coxa IV in all three families, i.e., postero-laterad to coxa IV in Nuttalliellidae (Roshdy et al. 1983), ventro-laterad in Argasidae (Roshdy et al. 1989; Pugh et al. 1991), and posterior to coxa IV in Ixodidae (Pugh et al. 1988, 1990). The spiracle consists of a spiracular plate, an ostium, an atrial cavity, and atrial muscles (Roshdy & Hefnawy 1973; Sonenshine 1991). The surface of the spiracular plate is covered with pores called aeropyles and has a macular region that forms the first part of the ostial region of the spiracle. Internally the spiracular plate is composed of cuticular pedicels that create a complex series of chambers. These pedicels and chambers lie on a thickened cuticular base that overlies the epidermal cells. Most of our information on the morphology of tick spiracular plates is from light microscopy of thick histological sections and scanning electron microscopy (Sixl et al. 1971; Woolley 1972; Roshdy 1974; Roshdy et al. 1983, 1989; Pugh et al. 1988, 1990, 1991; Schol et al. 1995). The only study using transmission electron microscopy is by Sixl & Sixl-Voight (1974) on Haemaphysalis inermis BIRULA 1895. The present study examines the morphology and ultrastructure of the nymphal and adult spiracular plate of Amblyomma americanum (LINNAEUS 1758) and compares it to that of several other species of hard ticks, Boophilus annulatus (SAY 1821), Demacentor variabilis (SAY 1821), Haemaphysalis leporispalustris (PACKARD 1869), and Rhipicephalus sanguineus (LATREILLE 1806).

Warble stage development of third instars of Hypoderma lineatum (Diptera: Oestridae).

Hypoderma lineatum (Villers), the common cattle grub, is an insect parasite that resides in a warble in the subcutaneous tissues of the backs of cattle during a portion of their life cycle. Inside the warble, the larva undergoes 2 molts to the 3rd instar. In this study, the development of the posterior spiracular plates of the 3rd instar of H. lineatum was observed in situ. Larvae were observed to molt to the 3rd-instar phase 1 stage of development 28.6 +/- 3.9 d (+/- SD) after digesting a breathing hole in the backs of previously uninfested calves. Development of the spiracular plates through each of the various recognizable stages occurred on a 5-6-d interval. It took 54.2 +/- 5.1 d in the back for larvae to develop to the phase 3 stage, the stage reached before larvae exit the host. The average elapsed time from the 3rd-instar phase 3 stage to exit from the host was 5.5 +/- 2.9 d. Of 22 larvae that were followed from arrival in the back to pupariation, the elapsed time was 59.4 +/- 6.1 d. Most larval mortality occurred in the back during the 1st and 2nd instar. Of larvae surviving to the 3rd instar, 86.7% successfully exited from the host. Of 3rd instars surviving to the phase 2 goldplate or phase 3 stage, 93.3% exited successfully from the host.

岡山県におけるマダニ類の人体刺咬 2 症例

Two tick bite cases (a 81-year-old woman and a 6-month-old boy) from Okayama Prefecture were additionally reported. The ticks were identified as an adult female of Haemaphysalis longicornis Neumann, 1901 (Case 1) and a nymph of H. flava Neumann, 1897 (Case 2) based on morphology of scutum, capitulum, internal spurs, spiracular plates and genital aperture. The tick bite seemed to have happened in a garden of her house in Case 1,while the place of bite was not clear in Case 2. The present report constitutes the 20th and 21st cases of hard tick infestation in Okayama Prefecture, Japan.

Life History and Description of Immature Stages of Euaresta stigmatica (Diptera: Tephritidae) on Ambrosia spp. (Asteraceae) in Southern California

Euaresta stigmatica Coquillett is bivoltine and nearly monophagous on four native ragweeds, Ambrosia spp. (Asteraceae), in the southwestern United States. In southern California, larvae of the spring (F 1 ) generation develop singly in and feed on one or both ovules of young fruiting involucres of Ambrosia ilicifolia (Gray) Payne, with a small proportion infesting the staminate involucres. Adults emerge after 1 mo, with their reproductive organs immature. The F 2 generation develops in the involucres of fall-blooming Ambrosia acanthicarpa Hooker. The egg is described and illustrated for the first time for any species of Euaresta. First, second, and third instars and the puparium are described and illustrated for the first time for E. stigmatica. The posterior spiracular plates of all three instars bear only three interspiracular processes, whereas the larvae and puparia of all other nonfrugivorous tephritids described to date bear four such processes. Adult behaviors described from field and laboratory studies include courtship, copulation, and territoriality. Male courtship displays include three behaviors previously undescribed for Tephritidae: a side-to-side dance, rapid side stepping, and n middle leg abduction. Hymenopterous parasitoids of E. stigmatica include two solitary, primary larval-pupal, endoparasitoids, Eurytoma sp. (Eurytomidae) and Pteromalus sp. (Pteromalidae). Potential use of E. stigmatica as a biological control agent for ragweeds in Eurasia is discussed

Morphology and structural organization of spiracles in female Argas (Persicargas) walkerae (Acari: Argasidae).

Scanning electron microscopical investigations of fractures and corrosion casts of the spiracles from female A. walkerae ticks revealed a four-part structure, consisting of spiracular plate, ostium and macula forming the external closure, followed by the subostial space and the vestibulum of regulable volume, as well as the atrial chamber as the innermost part from which the main tracheal trunks originate. On the average, the spiracular plate was 158 microns long and 188 microns at the broadest width. It consisted of a thin, highly perforated external and a thick internal layer, which enclosed the interpedicellar space with numerous stout pedicels. In its posterior region, the spiracular plate was covered by the macula, which was up to 80 microns in length and 110 microns in width. The interpedicellar cavity opened into the subostial space measuring 95.5 microns in length and 159.6 microns in width, which proceeded into the 112-microns long vestibulum. The roof of the vestibulum was flexible and could be everted and inverted. Inverted, the roof formed a quadratic bulge with numerous deep cuticular folds, which confined the lumen of the vestibulum either partially or completely. In corrosion casts, the roof was everted to a length of up to 89.3 microns. In the posterior part of the vestibulum, as well as in the initial fourth of the atrial chamber, numerous anvil-, cone- or drop-like cuticular projections were arranged in wedge-like fashion. The atrial chamber was almost spherical with a diameter of 138.4 microns. Five main tracheal trunks of different luminal diameter as well as numerous channels opened into the atrial chamber.