Pollination by Sexual Mimicry in Mormolyca ringens: A Floral Chemistry that Remarkably Matches the Pheromones of Virgin Queens of Scaptotrigona sp.

Abstract

The chemical composition of some volatile (2-heptanol) and nonvolatile constituents (a homologous 9-alkene/alkane series) of Mormolyca ringens flowers and Scaptotrigona sp. queen waxes (homologous 9-alkene/alkane series) and cephalic extracts (homologous series of 2-alkanols, including 2-heptanol) involved with the pseudocopulation or sexual mimicry in Orchidaceae pollination is compared. The similarity in chemical composition of flowers and insects is assigned to the chemically induced copulatory activity in Scaptotrigona males.

Nematophagous fungus Arthrobotrys oligospora mimics olfactory cues of sex and food to lure its nematode prey

“…For example, the American bolas spider Mastophora hutchinsoni produces odorants that mimic female moth sex pheromones to attract different moth species (Haynes et al, 2002). Orchids such as Ophrys sphegodes, O. exaltata and Mormolyca ringens produce volatile compounds that greatly resemble the chemical composition of female bee pheromones in order to attract the male bees as pollinators (Flach et al, 2006; Mant et al, 2005; Schiestl et al, 2000). Whether male Caenorhabditis nematodes produce any volatile sex pheromones is currently unknown, but a recent study has found that male pinewood nematodes Bursaphelenchus xylophilus produce an as yet unidentified volatile pheromone that attracts the females (Shinya et al, 2015).…”

A mixed colony of Scaptotrigona depilis and Nannotrigona testaceicornis (Hymenoptera, Apidae, Meliponina)

“…Hartfelder and Engels (1989) showed that the general composition of the larval food of these genera is very similar when compared to other genera. Furthermore, pollination of the orchid Mormolyca rigens by males of both genera through pseudo-copulation indicates that the pheromones involved in the attraction of the males are similar (Singer et al, 2004;Flach et al, 2006). These facts point to the possibility that Scaptotrigona and Nannotrigona use similar chemical substances for communication.…”

Cheaters and liars: chemical mimicry at its finestThe present review is one in the special series of reviews on animal-plant interactions.In memory of Jan Tengö (1939–2010), who made exceptional contributions to our understanding of the chemical ecology of solitary bees, including chemical mimicry.

“…These have been identified both in the epicuticular waxes of the flowers of the orchid mimic and the virgin queens of Scaptotrigona sp. (Flach et al 2006). Field observations and preliminary chemical analyses indicate that drones of N. testaceicornis also might be attracted by floral volatiles of M. ringens (Flach et al 2006), and that male fungus gnats that pollinate Lepanthes flowers track the floral scent upwind to its source, suggesting that floral scent is indeed likely to be the primary attractant (M. Blanco, personnal communication).…”

“…(Flach et al 2006). Field observations and preliminary chemical analyses indicate that drones of N. testaceicornis also might be attracted by floral volatiles of M. ringens (Flach et al 2006), and that male fungus gnats that pollinate Lepanthes flowers track the floral scent upwind to its source, suggesting that floral scent is indeed likely to be the primary attractant (M. Blanco, personnal communication). With their several hundreds, if not thousands, of orchid species, the Neotropics secretly hold a considerable share of fascinating orchid-pollinator interactions that call for greater scrutiny.…”