Unusual macrocyclic lactone sex pheromone of Parcoblatta lata , a primary food source of the endangered red-cockaded woodpecker

Abstract

Wood cockroaches in the genus Parcoblatta, comprising 12 species endemic to North America, are highly abundant in southeastern pine forests and represent an important prey of the endangered red-cockaded woodpecker, Picoides borealis. The broad wood cockroach, Parcoblatta lata, is among the largest and most abundant of the wood cockroaches, constituting >50% of the biomass of the woodpecker's diet. Because reproduction in red-cockaded woodpeckers is affected dramatically by seasonal and spatial changes in arthropod availability, monitoring P. lata populations could serve as a useful index of habitat suitability for woodpecker conservation and forest management efforts. Female P. lata emit a volatile, longdistance sex pheromone, which, once identified and synthesized, could be deployed for monitoring cockroach populations. We describe here the identification, synthesis, and confirmation of the chemical structure of this pheromone as (4Z,11Z)-oxacyclotrideca-4,11-dien-2-one [= (3Z,10Z)-dodecadienolide; herein referred to as "parcoblattalactone"]. This macrocyclic lactone is a previously unidentified natural product and a previously unknown pheromonal structure for cockroaches, highlighting the great chemical diversity that characterizes olfactory communication in cockroaches: Each long-range sex pheromone identified to date from different genera belongs to a different chemical class. Parcoblattalactone was biologically active in electrophysiological assays and attracted not only P. lata but also several other Parcoblatta species in pine forests, underscoring its utility in monitoring several endemic wood cockroach species in red-cockaded woodpecker habitats.pheromone monitoring | surveillance | wildlife conservation M any animals-especially nocturnal insects-have evolved sexually dimorphic sex pheromones as an efficient and relatively private communication channel for mate attraction and mate choice (1). Sex pheromones also function in species discrimination, and therefore pheromone blends also play prominent roles in premating reproductive isolation of closely related species and in speciation (1, 2).Most cockroach species are nocturnal, and they profoundly rely on pheromones for intraspecific communication. For example, females of the broad wood cockroach, Parcoblatta lata, a species endemic to pine forests of the southeastern United States, have short wings, are incapable of flight, and therefore have limited dispersal capability. However, by emitting a volatile sex pheromone sexually receptive females are able to recruit males, which are excellent flyers, efficiently (3). Females and nymphs thus are able to remain in the relatively protected habitat beneath the sloughing bark of decaying logs, whereas males incur the greater energetic cost of mate-finding and predation that is associated with greater movement. Our earlier behavioral observations suggested the presence of a female sex pheromone, emitted during a "calling" display, and anatomical and electrophysiological studies confirmed that female-specific ter...

Pheromones and Animal Behavior

“…For example, Periplaneta species use different combinations of molecules based on the unusual molecule periplanone. A recent identification follows the same pattern, with a previously unidentified natural product and a previously unknown pheromonal structure for cockroaches found for the main pheromone component of the cockroach Parcoblatta lata, a macrocyclic lactone, (4Z,11Z)oxacyclotrideca-4,11-dien-2-one (Eliyahu et al 2012). This molecule also forms a component of the pheromones of related species in the genus.…”

“…Even where unusual molecules are used as pheromones, closely related species tend to use variations on these, as if exploring chemical space from a new starting point. In cockroaches, each of the long-range sex pheromones identified to date from different cockroach genera belongs to a different chemical class, with species in each genus using different combinations of variations of the unusual molecule (Eliyahu et al 2012;Gemeno & Schal 2004). For example, Periplaneta species use different combinations of molecules based on the unusual molecule periplanone.…”

The use of the lactone motif in chemical communication

“…14) started from 10-bromo-1-decene which was transformed into the aldehyde 102 and coupled in a lithium- Fortunately, both macrocyclic lactones were active against the ash borer, so the blend of 2 : 1 had the potential to be a detection, mating disruptor or mass trapping agent, which could be used in emerald ash borer control. A related macrocyclic lactone, parcoblattalactone (110), is a sex pheromone of the broad wood cockroach, Parcoblatta lata, 122 found in the pine forests of southeastern USA. The 13-membered (3Z,10Z)-dodeca-3,10-dienolide (110) was synthesized by cyclization of the diyne precursor 108 and subsequent hydrogenation (Fig.…”

“…In this context, the high boiling components may serve as a xative to prevent the fast evaporation of ocimene from the female's scent pouch. 127 Large, unbranched terminally oxidized macrolides, ranging from 16-octadecanolide (117) to 26-hexacosanolide (122) have been identied in the Dufour's gland of various bees. The Dufour's gland ancestral function is cell lining, but a communicative role is derived in some cases.…”

(R)-Desmolactone Is a Sex Pheromone or Sex Attractant for the Endangered Valley Elderberry Longhorn Beetle Desmocerus californicus dimorphus and Several Congeners (Cerambycidae: Lepturinae)

“…The same characteristics of sensitivity and selectivity should make pheromone-based sampling methods an ideal means of detecting and sampling rare, threatened, or endangered species. Despite these obvious advantages, pheromone-based methods have been exploited for these purposes in only a very few cases (e.g., the moth Actias ( = Graellsia ) isabellae (Graëlls) [7] , [8] ; wood cockroaches as food for endangered bird species [9] ; the scarab beetle Osmoderma eremita Scopoli and the click beetle Elater ferrugineus L. [10] ) in part because of the high cost of identifying and developing pheromones as a means to study populations of rare or endangered species [10] .…”