蛾類毛蟲毒刺 true setae

 蛾類毛蟲毒刺 true setae

 

 true setae 如 C 圖中間，沒有和細胞相連，很容易脫落，在微風的條件下，可以長距離飄行，在毛蟲範圍100內 很容易碰到。

針直徑 1~2 um，只有頭髮直徑約 1/80

針的長度 50 um，只有頭髮直徑約 1/2

Fig. 1. The true setae and a setae field (mirror) of O.  lunifer: (A) a seta is sharp at the proximal end facilitating penetration of the skin and mucous membranes of animals, and backward-pointing barbs allow forward only migration through the tissue as an animal moves; (B) the proximal ends of true setae are embedded into pits in the cuticle but not attached to the integumen

Fig. 2. Schematic maps of setae fields on typical examples of 3rd–8th instars of O. lunifer caterpillars. The pattern on 7th instar larvae is variable. Head capsule widths are approximate and typical for the given instar.

Fig. 3. Two size classes of the commonly-described true setae are found in each setae field of O. lunifer: A, compound micrograph of a clump of true setae removed from a setae field; (B) the proportion of short setae is greater on older instars

Fig. 4. Thin true setae are found in the anterior setae fields of abdominal segment 1 on O. lunifer larva: (A) thin setae are long, narrow and somewhat bendable; (B) the length and width of thin (triangles) and previouslydescribed true setae (circles) compared (paired data from the same larva).

True setae borne on the abdominal tergites of Ochrogaster lunifer Herrich-Schӓffer caterpillars are the agents of an irritating contact dermatitis, osteomyelitis, ophthalmia, and severe allergic reactions in humans, and are the cause of Equine Amnionitis and Fetal Loss in Australia. The setae are detached and readily dislodge from the integument whereby they disperse throughout the environment. To better understand the true setae of O. lunifer as agents of medical and veterinary concern, we studied their characteristics and distance dispersed. Whereas members of the European Thaumetopoeinae have been widely studied, their southern-hemisphere counterparts such as O. lunifer are not well known despite their harmfulness and known medical and veterinary importance. The caterpillar’s investment in true setae increased with age and size, and two distinct size classes co-occurred in setae fields. A previously undescribed morphological type of true seta was found on the first abdominal segment. All true setae were calculated to travel long distances in the air even under light breeze conditions. Our results show there is a high risk of exposure to airborne urticating setae within 100 m of elevated caterpillar activity, and a likely risk of exposure for some kilometers in the direction of the prevailing breeze. This information should be used to inform management strategies in areas where urticating processionary caterpillars are active, and especially during periods of an outbreak.

True setae of the female H. oratex. (a) general view; (b) base; (c) medial portion, arrow indicates a longitudinal groove; (d) apex, arrow indicates the apical groove (scales = 25, 03, 05, 05 µm, respectively).  

-Modifi ed setae of the female H. oratex. (a) general view (asterisk); (b) pointed projections at base; (c) medial portion; (d) apex, arrow indicates apical orifi ces (scales = 200, 25, 10, 05 µm, respectively).  

-Egg mass of H. oratex. (a) egg mass on a branch of the host plant; (b) detail of the layer composed of true and modifi ed setae (scales = 5 mm; 200 µm, respectively).  

Figure 4. Venom components of different caterpillar species and their role on human body targets in the pathophysiology. Caterpillar venoms contain pharmacologically active components that are able to interfere with targets in the normal human cellular physiology. Some components are responsible for the local effects such as inflammation, erythema, edema, intense itch, tissue damage, pain and may exert an allergic reaction. Others affect the hemostasis by acting on the coagulation cascade or on the fibrinolytic pathway. Venom components colored in green activate a step in the cascade, while the components colored in red are able to inhibit a step. In some cases, this can lead to the development of an acute kidney injury (AKI). The venom-induced AKI cascade in the figure is copied with permission from [50].

Variation in Morphology and Airborne Dispersal of the Urticating Apparatus of Ochrogaster lunifer (Lepidoptera:Notodontidae), an Australian Processionary Caterpillar, and Implications for Livestock and Humans

 

資料來源:

Lynda E. Perkins,

1, Bronwen W. Cribb,

1,2

 Dan E. Pagendam,

3

 and Myron P. Zalucki1,4,

1

School of Biological Science, The University of Queensland, Brisbane, QLD 4072, Australia, 2

Centre for Microscopy & Microanalysis,

The University of Queensland, Brisbane, QLD 4072, Australia, 3

CSIRO Data61, Dutton Park, QLD 4102, Australia, and 4

Corresponding

author, e-mail: m.zalucki@uq.edu.au

Subject Editor: Phyllis Weintraub

Received 27 August 2019; Editorial decision 24 October 2019

Abdominal macrochaetae of female Hylesia oratex Dyar, 1913 (Insecta: Lepidoptera: Saturniidae): External morphology and medical significance

Article

Full-text available

Aug 2015

Review Caterpillar Venom: A Health Hazard of the 21st Century Andrea Seldeslachts , Steve Peigneur and Jan Tytgat * Toxicology and Pharmacology, KU Leuven, Campus Gasthuisberg, O & N2, Herestraat 49, P.O. Box 922, 3000 Leuven, Belgium; andrea.seldeslachts@kuleuven.be (A.S.); steve.peigneur@kuleuven.be (S.P.) * Correspondence: jan.tytgat@kuleuven.be Received: 30 April 2020; Accepted: 24 May 2020; Published: 30 May 2020