The frontal weapon of the termite Armitermes euamignathus Silvestri (Isoptera, Termitidae, Nasutitermitinae)

Costa-Leonardo, Ana Maria

doi:10.1590/S0101-81752001000200012

Abstract

Frontal weapon is the term used to designate the apparatus consisting of frontal gland and associated structures that participate in the chemical defense of termite soldiers. The ultra structure of the frontal gland and the scanning microscopy of the soldier head was investigated in the termite Amiitermes euamignathus Silvestri, 1901.Campaniform sensilla was not observed but there were 80 to100 sensory bristles around the frontal pore. The glandular epithelium shows only class 1 cells according 10 the classification of NOIROT & QUENNEDEY (1974, 1991). The glandular cells are characterized by apical microvilli, a basal labyrinth and a large quantity of smooth endoplasmic reticulum which forms dense zones throughout the cytoplasm. The secretion is concentrated mainly in the basal pole of the cell and consists of large lipid droplets. The secretory epithelium is covered by a thick apical cuticle composed of a thin outer epicuticle, a layer of epicuticular filaments and a dense procuticle. The cytological results concerning the frontal pore showed a reduced cuticle and the presence of a subcuticular space where the lipid droplets are accumulated. The lack of class 3 cells and the presence of an intrinsic musculature are two anatomical features of the A. euamignathus frontal gland that will be important in the phylogenetic relationships of the Nasutitermitinae.

Isoptera; Armitermes euamignathus; frontal weapon; frontal gland; exocrine glands

The frontal weapon of the termite Armitermes euamignathus Silvestri (Isoptera, Termitidae, Nasutitermitinae)

Ana Maria Costa-Leonardo

Departamento de Biologia, Instituto de Biociências, Universidade Estadual Paulista. Caixa Postal 199, 13506-900, Rio Claro, São Paulo, Brasil. E-mail: amcl@rc.unesp.br

ABSTRACT

Frontal weapon is the term used to designate the apparatus consisting of frontal gland and associated structures that participate in the chemical defense of termite soldiers. The ultra structure of the frontal gland and the scanning microscopy of the soldier head was investigated in the termite Amiitermes euamignathus Silvestri, 1901.Campaniform sensilla was not observed but there were 80 to100 sensory bristles around the frontal pore. The glandular epithelium shows only class 1 cells according 10 the classification of NOIROT & QUENNEDEY (1974, 1991). The glandular cells are characterized by apical microvilli, a basal labyrinth and a large quantity of smooth endoplasmic reticulum which forms dense zones throughout the cytoplasm. The secretion is concentrated mainly in the basal pole of the cell and consists of large lipid droplets. The secretory epithelium is covered by a thick apical cuticle composed of a thin outer epicuticle, a layer of epicuticular filaments and a dense procuticle. The cytological results concerning the frontal pore showed a reduced cuticle and the presence of a subcuticular space where the lipid droplets are accumulated. The lack of class 3 cells and the presence of an intrinsic musculature are two anatomical features of the A. euamignathus frontal gland that will be important in the phylogenetic relationships of the Nasutitermitinae.

Key words: Isoptera, Armitermes euamignathus, frontal weapon, frontal gland, exocrine glands

Full text available only in PDF format.

ACKNOWLEDGEMENTS. The author thanks Dr. Kathleen S. Shields for help with the scanning microscopy and CNPq for financial support.

Recebido em 17.VIII.2000; aceito em 15.V.2001.

References

ARAUJO, J. & J.M. PASTEELS. 1985. Ultrastructure de la glande défensive de Drusilla canaliculata Fab. (Coleoptera, Staphylinidae). Arch. Biol, 96:81-99.
BIILEN, J. 1986. Comparative morphology and ultrastructure of the Dufour gland in ants (Hymenoptera, Formicidae). Entomol. Gener. 11:165-181.
______. 1990. Morphology and ultrastructure of the Dufour's and venom gland in the ant Myrmecia gulosa (Fabr.)(Hymenoptera: Formicidae). Aust. Jour. Zool. 38:305-315.
CHAPMAN, R.F. 1998. The insects. Structure and Function. Cambridge, Cambridge Univ. Press, 770p.
COSTA-LEONARDO, A.M. 1992. The secretory epithelium of the frontal gland in Velocitermes sp. soldiers (Isoptera, Termitidae). Naturalia 17:99-109.
______. 1998. Morphology of the frontal weapon in the soldier caste of Cornitermes cumulans (lsoptera, Termitidae). Rev. Bras. Ent. 41(2-4):195-197.
COSTA-LEONARDO, A.M. & C.R. DE SALVO. 1987. A comparative study of the frontal glands in three species of Brazilian termite soldiers (Isoptera, Tennitidae). Revta bras. Ent. 31(3):465-71.
DELIGNE, J., A. QUENNEDEY & M.S. BLUM. 1981. The enemies and defense mechanisms of termites, p. 1-76. In: H.R. HERMANN (Ed.). Social Insects. New York, Academic Press, Vol. 2, 491p.
DOMINGOS, DJ. 1985. Densidade e distribuição espacial de ninhos de duas espécies de Armitermes (Isoptera, Tennitidae) em cinco formações vegetais do cerrado. Rev. Brasil. Biol. 45(3):233-240.
FOLDI, I. 1981. Ultrastructure of the wax-gland system in subterranean scale insects (Homoptera, Coccoidea, Margarodidae). Jour. Morphol. 168:159-170.
GONTIJO, T.A. & DJ. DOMINGOS. 1991. Guild distribution of some termites from cerrado vegetation in south-east Brazil. Jour. Trop. Ecol. 7:523-529.
HOWSE, P.E. 1984. Sociochemicals of termites, p. 475-519. In: W.J. BELL & R.T. CARDÉ(Eds). Chemical Ecology of Insects. New York, Chapman & Hall, 519p.
LANE, N.J.; G. MARTINUCCI; R. DALLAI & P. BURIGHEL. 1994. Electron microscopic structure and evolution of epithelial junctions, p. 23-43. In: S. CITI (Ed.). Molecular mechanisms of epithelial cell junctions: from development to disease. Austin, R.G. Landes Co., 308p.
NOIROT, C. & A. QUENNEDEY. 1974. Fine structure of insect epidermal glands. Annu. Rev. Entomol. 19:61-80.
______. 1991. Glands, gland cells, glandular units: Some comments on terminology and classification. Ann. Soc. Ent. Fr., n.s., 27:123-128.
PERCY-CUNNINGHAM, J.E. & J.A. MACDONALD. 1987. Biology and ultrastructure of sex pheromone-producing glands, p. 27-75. In: G.D. PRESTWICH & G. J. BLOMQUIST (Eds). Pheromone Biochemistry. New York, Praeger Scientific, 565p.
PRESTWICH, G.D. 1982. From tetracycles to macrocyles. Tetrahedron 38(13):1911-1919.
______. 1984. Defense mechanisms of termites. Ann. Rev. Entomol. 29:201-232.
QUENNEDEY, A. 1972. Les glandes exocrines des termites. III. Structure fine de la glande sternale de Trinervitermes geminatus Wasman (Termitidae, Nasutitermitinae). Z. Zellforsch. 130:205-218.
______. 1984. Morphology and ultrastructure of termite defense glands, p. 151-200. In: H.R. HERMANN (Ed.). Defensive mechanisms in social insects. New York, Praeger Scientific, 259p.
______. 1998. Insect epidermal gland cells: ultrastructure and morphogenesis, p. 177-207. In: F.W. HARRISON (Ed.). Microscopic Anatomy Invertebrates. New York, Wiley-Liss Inc. Press, Vol. 11, 381p.
QUENNEDEY, A. & J. DELIGNE. 1975. L'arme frontale des soldats de termites. I. Rhinotermitidae. Ins. Soc. 22(3):243-267.
WAKU, Y. & A.I. FOLDI. 1984. The fine structure of insect glands secreting waxy substances, p. 303-322. In: R.C. KING & H. AKAI (Eds). Insect ultrastructure. New York, Plenum Press, Vol. 2, 485p.

Publication Dates

Publication in this collection
04 May 2009
Date of issue
June 2001

History

Accepted
15 May 2001
Received
17 Aug 2000

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

[1] ARAUJO, J. & J.M. PASTEELS. 1985. Ultrastructure de la glande défensive de Drusilla canaliculata Fab. (Coleoptera, Staphylinidae). Arch. Biol, 96:81-99.

[2] BIILEN, J. 1986. Comparative morphology and ultrastructure of the Dufour gland in ants (Hymenoptera, Formicidae). Entomol. Gener. 11:165-181.

[3] ______. 1990. Morphology and ultrastructure of the Dufour's and venom gland in the ant Myrmecia gulosa (Fabr.)(Hymenoptera: Formicidae). Aust. Jour. Zool. 38:305-315.

[4] CHAPMAN, R.F. 1998. The insects. Structure and Function. Cambridge, Cambridge Univ. Press, 770p.

[5] COSTA-LEONARDO, A.M. 1992. The secretory epithelium of the frontal gland in Velocitermes sp. soldiers (Isoptera, Termitidae). Naturalia 17:99-109.

[6] ______. 1998. Morphology of the frontal weapon in the soldier caste of Cornitermes cumulans (lsoptera, Termitidae). Rev. Bras. Ent. 41(2-4):195-197.

[7] COSTA-LEONARDO, A.M. & C.R. DE SALVO. 1987. A comparative study of the frontal glands in three species of Brazilian termite soldiers (Isoptera, Tennitidae). Revta bras. Ent. 31(3):465-71.

[8] DELIGNE, J., A. QUENNEDEY & M.S. BLUM. 1981. The enemies and defense mechanisms of termites, p. 1-76. In: H.R. HERMANN (Ed.). Social Insects. New York, Academic Press, Vol. 2, 491p.

[9] DOMINGOS, DJ. 1985. Densidade e distribuição espacial de ninhos de duas espécies de Armitermes (Isoptera, Tennitidae) em cinco formações vegetais do cerrado. Rev. Brasil. Biol. 45(3):233-240.

[10] FOLDI, I. 1981. Ultrastructure of the wax-gland system in subterranean scale insects (Homoptera, Coccoidea, Margarodidae). Jour. Morphol. 168:159-170.

[11] GONTIJO, T.A. & DJ. DOMINGOS. 1991. Guild distribution of some termites from cerrado vegetation in south-east Brazil. Jour. Trop. Ecol. 7:523-529.

[12] HOWSE, P.E. 1984. Sociochemicals of termites, p. 475-519. In: W.J. BELL & R.T. CARDÉ(Eds). Chemical Ecology of Insects. New York, Chapman & Hall, 519p.

[13] LANE, N.J.; G. MARTINUCCI; R. DALLAI & P. BURIGHEL. 1994. Electron microscopic structure and evolution of epithelial junctions, p. 23-43. In: S. CITI (Ed.). Molecular mechanisms of epithelial cell junctions: from development to disease. Austin, R.G. Landes Co., 308p.

[14] NOIROT, C. & A. QUENNEDEY. 1974. Fine structure of insect epidermal glands. Annu. Rev. Entomol. 19:61-80.

[15] ______. 1991. Glands, gland cells, glandular units: Some comments on terminology and classification. Ann. Soc. Ent. Fr., n.s., 27:123-128.

[16] PERCY-CUNNINGHAM, J.E. & J.A. MACDONALD. 1987. Biology and ultrastructure of sex pheromone-producing glands, p. 27-75. In: G.D. PRESTWICH & G. J. BLOMQUIST (Eds). Pheromone Biochemistry. New York, Praeger Scientific, 565p.

[17] PRESTWICH, G.D. 1982. From tetracycles to macrocyles. Tetrahedron 38(13):1911-1919.

[18] ______. 1984. Defense mechanisms of termites. Ann. Rev. Entomol. 29:201-232.

[19] QUENNEDEY, A. 1972. Les glandes exocrines des termites. III. Structure fine de la glande sternale de Trinervitermes geminatus Wasman (Termitidae, Nasutitermitinae). Z. Zellforsch. 130:205-218.

[20] ______. 1984. Morphology and ultrastructure of termite defense glands, p. 151-200. In: H.R. HERMANN (Ed.). Defensive mechanisms in social insects. New York, Praeger Scientific, 259p.

[21] ______. 1998. Insect epidermal gland cells: ultrastructure and morphogenesis, p. 177-207. In: F.W. HARRISON (Ed.). Microscopic Anatomy Invertebrates. New York, Wiley-Liss Inc. Press, Vol. 11, 381p.

[22] QUENNEDEY, A. & J. DELIGNE. 1975. L'arme frontale des soldats de termites. I. Rhinotermitidae. Ins. Soc. 22(3):243-267.

[23] WAKU, Y. & A.I. FOLDI. 1984. The fine structure of insect glands secreting waxy substances, p. 303-322. In: R.C. KING & H. AKAI (Eds). Insect ultrastructure. New York, Plenum Press, Vol. 2, 485p.