Setae Of Larvae Research Articles

Human exposure to larvae of processionary moths in France: study of symptomatic cases registered by the French poison control centres between 2012 and 2019

Context Contact with the setae of larvae (caterpillars) of pine or oak processionary moths could induce urticarial or allergic reactions in humans. These species are present in France and presently expanding towards highly populated areas due to climate change and/or human-mediated translocations. We aimed to describe the symptomatic cases of exposure to processionary larvae in France. Methods We conducted a retrospective study of symptomatic cases of exposure to processionary larvae registered by the French poison control centres between 1 January 2012 and 31 July 2019. We reviewed all medical records coded with the agent “larvae”. Results Of the 1274 included cases, 59% and 27% corresponded to pine and oak processionary larvae, respectively; the 14% remaining cases concerned unspecified processionary larvae. While the annual number of cases due to pine processionary larvae fluctuated during the study period, cases associated with oak processionary larvae increased steadily. Most of the annual cases occurred between January and May for pine processionary larvae, and April and August for oak processionary larvae (with a peak in March or June, respectively). Among the 1022 cases for which information was available, the sex ratio was 1.2 and the median age was 11 years old. Skin symptoms were reported by 96,3% of the cases, such as pruritus or urticaria. The severity was mild in 96.3% of cases, moderate in 3.5%, and severe in 0.2% (two cases). Ocular or oral exposures led more frequently to severe symptoms than dermal ones (respectively 31% and 18% vs. 2% of cases, p < 10−3). Conclusion Since processionary moth larvae exposure is a growing health concern, which can cause severe injuries particularly after ocular or oral exposures, the population, and the professionals should be informed of existing recommendations to avoid exposure and measures to be taken after being exposed.

Morphological changes in Neoseiulus californicus (Acari: Phytoseiidae).

This paper deals with the detailed morphological observation of larva, protonymph and deutonymph, as well as female and male adults of Neoseiulus californicus (McGregor) based on laboratory reared specimens. The main changes are as follows: larva with one dorsal shield, while protonymph with two, which fused into a holodorsal shield in deutonymph; 9 pairs of dorsal setae in larvae, 14 pairs in protonymph, and 19 pairs in deutonymph and adult; the immature stages without discernible ventrianal shield, though hypoplastic shield, a weakly sclerotized small plate around the anal pore, present in the protonymph and deutonymph. larva and protonymph each with seven pairs of ventral setae, while deutonymph and adult each with 12 pairs; movable digit with one or two teeth in larva, three teeth in protonymph, deutonymph or adult. The development of morphological traits in ontogenesis of N. californicus could provide helpful basis to identify it practically from its relatives.

Achipteria sgardelisi sp. nov. (Acari, Oribatida, Achipteriidae) from Greece and its morphological ontogeny

Achipteria sgardelisi sp. nov. and its morphological ontogeny is described and illustrated. The adult of this species has a clavate bothridial seta, with a barbed head distally, which is not common in Achipteria Berlese, 1885; in most species the head is smooth. Notogastral setae c2 and la are long, while the other setae are short, and rounded porose areas are present, of which Aa is the largest. Genua I and II lack anteroventral apophysis, genu IV is approximately as long as tibia IV, and setae bv'' and v'' on femur I and l' on femur III are short. All prodorsal setae of juveniles are minute. Most gastronotal setae of larva are short, thick and barbed, except for minute c-series and smooth h2, whereas most gastronotal setae of nymphs are minute, except for short, thick and barbed lp and h-series. Leg claws of all instars are smooth. The morphology of the adult and juveniles of A. sgardelisi is compared with congeners.

Morphological ontogeny of Hydrozetes paulista (Acari, Oribatida, Hydrozetidae), with comments on Hydrozetes Grandjean

The morphological ontogeny of Hydrozetes paulista Pérez-Íñigo &amp; Baggio, 1989 is described and illustrated. This species is monodactylous as adult, with short, setiform bothridial seta and belongs to the “lacustris species group”. It has 13 pairs of notogastral setae, including c2, but seta c3 is retained by some individuals. Most gastronotal setae of larva are of medium size and barbed, except for longer setae lm, lp and h2, and short and smooth c1 and h3. In the nymphs setae of l-series, h1 and h2 are very long, smooth and dark pigmented, setae h3 and p1 are of medium size, thick, pointed and barbed, and other setae are short and usually smooth; seta lm is located anterior to the gland opening. Hydrozetes paulista is bisexual, but in this study only females were present.

Juvenile instars of Siculobata (Paraleius) leontonycha (Acari, Oribatida, Scheloribatidae)

Abstract The morphology of juvenile instars of the oribatid mite, Siculobata (Paraleius) leontonycha (Berlese, 1910) is described and illustrated, based on material collected from the galleries of bark beetles, Ips typographus L. (Coleoptera, Curculionidae, Scolytinae) under the bark of Picea obovata in Western Siberia, Russia. Juveniles are characterized by folded gastronotum and anogenital region, well-developed, setiform, barbed prodorsal setae, clavate bothridial setae, 11 pairs of gastronotic setae in larva and 15 pairs in nymphs, all with excentrosclerites, thick or slightly broadened in median parts, erect, barbed (except setiform p1-p3 in protonymph), epimeral formulas 3-1-2-1 in protonymph, 3-1-2-2 in deutonymph and 3-1-3-2 in tritonymph, ontogeny of genital, aggenital, adanal anal setal formulas 0-1-2-3, 0-0-1-1, 0-0-3-3, 0-0-0-2, respectively. The morphological differences of ontogenetic instars for S. (Paraleius) leontonycha to known species of Scheloribatidae are given.

Differentiation of external morphology of Oribatella Banks, 1895 (Acari: Oribatida: Oribatellidae), in light of the ontogeny of three species

Differentiation of external morphology of Oribatella Banks, 1895 was investigated, in light of the ontogeny of O. quadricornuta (Michael, 1880), O. superbula (Berlese,1904) and O. calcarata (CL Koch, 1835) studied here for the first time, and that of the other species from the literature. The pattern of gastronotal setae in larvae is similar, except for lack of seta h 3 in O. nortoni Behan-Pelletier, 2011, while that of nymphs and adults is differentiated. The nymphs of most species have 15 pairs of gastronotal setae, but those of O. metzi Behan-Pelletier, 2011 and most nymphs of O. calcarata have 13 pairs. The nymphs of most species carry the exuvial scalps of previous instars on apical parts of gastronotal setae da, while setae dm and dp, located under these scalps, are subjected to translocation, reduction in size or loss. In O. berlesei (Michael, 1898), O. nortoni, O. quadricornuta and O. sexdentata Berlese, 1916 pair dp takes a more lateral position, compared with the larvae, in O. superbula and O. canadensis Behan-Pelletier and Eamer, 2010 it is reduced in size (in the latter species pair dm is also reduced), while O. metzi loses setae dm and dp. In contrast, the nymphs of O. calcarata do not carry the scalps, and usually lose setae c 1 and dm. The adults of all species lose setae c 1, c 3 and d-series, compared with the tritonymph, and only 10 pairs of notogastral setae remain (c 2, l-, h- and p-series), but O. quadricornuta and O. calcarata rarely retain seta c 3 unilaterally, which indicates the order of setal loss in Oribatella according to Shaldybina (1972).

Ontogenetic stages of Gymnodamaeus irregularis, with remarks on morphology of the juveniles of Gymnodamaeidae (Acari: Oribatida: Plateremaeoidea)

The juvenile stages of oribatid mites of the family Gymnodamaeidae are insufficiently known, and little information is available on the morphology of ontogenetic stages. Comparative characteristics of juvenile stages of species belonging to family Gymnodamaeidae are given based on our own data and available literature sources. Herein, the morphology of ontogenetic instars of Gymnodamaeus irregularis Bayartogtokh & Schatz, 2009 is investigated. The larva and nymphs are generally similar in their habitus. Basic characteristics in juveniles are the less sclerotized and unpigmented body with granulate surface of gastronotum, larva with 11 pairs of gastronotal setae (h3 absent) and nymphs with 10 pairs of gastronotal setae (setae la, lm and d-series absent, but setae lp and p-series present). Nymphs with ridge-like structure on prodorsum, and large excrescence on posterior end of gastronotum, bearing one pair of long (h1 ) and another pair of medium-long (p1 ) setae. All prodorsal, notogastral and adanal setae of larva and nymphs are densely barbed throughout. Conspicuous characters in the larval stage are the very long interlamellar setae, which are reduced in nymphs and adults to minute setae and the subequal lengths of gastronotal setae. All stages of nymphs carry gastronotic exuviae with reticulate granular sculpture of the previous instars. Adults are coated with thick cerotegument on the idiosoma, legs and most body setae. The sensillus is dilated in its distal part and covered with cerotegument. The notogaster has two pairs of irregular longitudinal ridge-like structures (procuticle); five pairs of notogastral setae; and a pair of strongly developed tubercles Sp on epimeral region III. Gymnodamaeus irregularis is a Western Palaearctic species, currently known from Central (East Tyrol, Austria) and Eastern Europe (Nizhny Novgorod region, Russia) and appears to be primarily an inhabitant of mosses and litter, and it prefers the xeric habitats.

Ontogenetic Development of Olfactory Organs in Grass Shrimp, Pandalus Kessleri (Decapoda, Pandalidae)

Ontogenetic Development of Olfactory Organs in Grass Shrimp,Pandalus Kessleri(Decapoda, Pandalidae)The olfactory organ in decapod crustaceans is represented by the outer antennular flagellum with specialized sensilla called aesthetascs. Characteristic structures of the lateral antennular flagellum with olfactory setae in larvae, juveniles and adults of grass shrimpPandalus kessleriCzerniavski, 1878 are described.

Morphology and structural organization of Haller's organ during postembryonic development ofArgas (Persicargas) walkerae (Ixodoidea: Argasidae)

Scanning-electron-microscopic investigations of Haller's organ in larvae, nymphs I, II, III and IV, and male and female adult Argas (Persicargas) walkerae ticks showed that morphology and structural organization change during postembryonic development. Stage-dependent differences existed regarding setal numbers of the anterior pit as well as formation and reticulation of cuticular projections in the capsule cavity. The anterior pit increased in size in the course of postembryonic development. It contained only seven setae in larvae, one conical, setiform and grooved seta each as well as two porose and fine setae. Nymphs I, II, III and IV adult ticks had equal numbers of setae; however, one additional unilaterally serrate and grooved seta each were present. Setal length increased continuously during postembryonic development and attained maximum values in adult ticks. The capsule consisted of roof and cavity and was located distinctly lateral in larvae, slightly lateral in nymphs I and II, and in all other stages directly on the longitudinal axis of tarsus. The capsule roof showed a reticular structure. The slit-like main aperture was located peripherally and arranged transversally to the longitudinal axis of tarsus I in larvae. Nymphs and adult ticks had a central, circular main aperture. Stage-dependent cuticular projections of varying form protruded into the capsule cavity. Larvae had only single, free-standing projections which ramified slightly and communicated with each other. Projections were more heavily reticulated in nymphs I and II. In nymphs III and IV as well as male and female adult ticks, a long centrally situated tube of reticular appearance was seen, which was supported by a large number of radially organized and interlocking pillars and communicated with the capsule roof. In all tick stages there were always four porose setae present, arranged on the capsule floor.