Polarization Microscopy and Infrared Microspectroscopy of Integument Coverings of Diapausing Larvae in Two Distantly Related Nonsocial Bees

Autor(es)

Mello, Maria Luiza S. ^[1] ; Vidal, Benedicto de Campos ^[1] ; Rozen, Jr., Jerome G. ^[2]

Afiliação do(s) autor(es)

^[1] Univ Estadual Campinas, Inst Biol, Dept Struct & Funct Biol, BR-13083862 Campinas, SP - Brazil

^[2] Amer Museum Nat Hist, Div Invertebrate Zool, Cent Pk West, 79th St, New York, NY 10024 - USA

• Tipo de documento: Artigo Científico
• Fonte: Microscopy and Microanalysis; v. 24, n. 1, p. 75-81, FEB 2018.
• Citações Web of Science: 0

Resumo

The larvae of the two distantly related nonsocial bees Ericrocis lata (Apidae) and Hesperapis (Carinapis) rhodocerata (Melittidae), which develop mostly under arid desert areas of North America, and that differ in that they either spin (E. lata) or do not spin (H. rhodocerata) protective cocoons before entering diapause, produce transparent films that cover the larval integument. To understand the nature of these films, their responses to topochemical tests and their characteristics when examined with fluorescence and high-performance polarization microscopy and microspectroscopy were studied. A positive staining by Sudan black B, birefringence of negative sign, and a Fourier transform-infrared (FT-IR) spectrum typical of lipids were detected for the integument covering of both species. The FT-IR signature, particularly, suggests a wax chemical composition for these lipid coverings, resembling the waxes that are used as construction materials in the honey cells produced by social bees. Considering the arid environmental conditions under which these larvae develop, we hypothesize that their covering films may have evolved as protection against water depletion. This hypothesis seems especially appropriate for H. rhodocerata larvae, which are capable of undergoing a long diapause period in the absence of a protective cocoon. (AU)

• Processo FAPESP: 07/58251-8 - Estrutura 3-D helicoidal, propriedades anisotrópicas ópticas e transformada de Fourier-infravermelho de fibras de colágeno em Chordae tendinae
• Beneficiário: Benedicto de Campos Vidal
• Modalidade de apoio: Auxílio à Pesquisa - Regular