Veneno De Cienpiés

Int. J. Morphol., 28(1):19-25, 2010.

Morphology, Histology and Histochemistry of the Venom Apparatus of the Centipede, Scolopendra valida (Chilopoda, Scolopendridae)
Morfología, Histología e Histoquímica del Aparato Venenoso del Ciempiés, Scolopendra valida (Chilopoda, Scolopendridae)

Bashir M. Jarrar

JARRAR, B. M. Morphology, histology and histochemistry of the venom apparatus of thecentipede, Scolopendra valida ( Chilopoda, Scolopendridae). Int. J. Morphol., 28(1):19-25, 2010. SUMMARY: Morphological, histological and histochemical characterizations of the venom apparatus of the centapede, S. valida have been investigated. The venom apparatus of Scolopendra valida consists of a pair of maxillipedes and venom glands situated anteriorly in the prosoma on either side of the firstsegment of the body. Each venom gland is continuous with a hollow tubular claw possessing a sharp tip and subterminal pore located on the outer curvature. The glandular epithelium is folded and consists of a mass of secretory epithelium, covered by a sheath of striated muscles. The secretory epithelium consists of high columnar venom-producing cells having dense cytoplasmic venom granules. Theglandular canal lacks musculature and is lined with chitinous internal layer and simple cuboidal epithelium. The histochemical results indicate that the venom-producing cells of both glands elaborate glycosaminoglycan, acid mucosubstances, certain amino acids and proteins, but are devoid of glycogen. The structure and secretions of centipede venom glands are discussed within the context of thepresent results. KEY WORDS: Scolopendra valida; Venom apparatus; Microanatomy; Centapede; Saudi Arabia.

INTRODUCTION

Centipedes are distributed widely, especially in warm, temperate and tropical region (Norris, 1999; Lewis, 1981, 1996). Of 3000 species of centipedes have been identified, 620 species were identified of medical importance and dangerous species belong to the genus Scolopedra(Norris; Stewart, 1997). Nine species of centipedes were recorded and described in Saudi Arabia, of which five species of Scolopendridae have been reported to be present in various localities in Saudi Arabia (Lewis, 1986; Lewis & Wrinik, 1990). Scolopendra valida is the largest centipede in Saudi Arabia and it is distinguished from other species by the ring suture on the first tergite (Lewis, 1986).Centipede stings occur in the warmer climates throughout the world and their painful results have been known for centuries. The centipede venom is toxic to both mammals and insects (Menez et al., 1990). The bites of

centipedes have been reported to cause constitutional and systemic symptoms including: severe pain, local pruritus, headache, nausea, vomiting, anxiety, palpitation, local tissueswelling, erythema, necrosis, lymph node swelling, ischemia and rhabdomyolysis (Bush et al., 2001; Ozsarac et al., 2001; Serinken et al., 2005; Yildiz et al., 2006; Vazirianzadeh et al., 2007). Nearly about five thousands centipede bites are reported every year in Turkey (Serinken et al.) and documented reports regarding Scolopendra valida biting appeared recently from Iran (Vazirianzadeh et al.), withno reports regarding centipede biting in Saudi Arabia. According to Lewis (1986), death from centipedes bites are extremely rare and the reports of fatalities should be treated with caution. However, a seven year old girl in the Philipines died after being bitten by Scolopendra subspinipes (Remington, 1950; Norris), while no fatality due to centipede stings has been reported in Saudi Arabia. Thelargest species

Department of Clinical Laboratory Sciences, Al-Jouf University, Saudi Arabia.

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JARRAR, B. M. Morphology, histology and histochemistry of the venom apparatus of the centipede, Scolopendra valida ( Chilopoda, Scolopendridae). Int. J. Morphol., 28(1):19-25, 2010.

are known to kill small vertebrates including some birds, reptiles and mammals. Few studies have focused on...