The Cryptocercus punctulatus species complex (Dictyoptera: Cryptocercidae) in the eastern United States: comparison of cuticular hydrocarbons, chromosome number, and DNA sequences.

The goal of the current study was to determine if cuticular hydrocarbons could be used to empirically delimit taxa within the Cryptocercus punctulatus species complex in the eastern United States. Cockroaches were collected from rotting logs in 22 locations across four states. Hydrocarbon phenotypes and two mitochondrial (16S and COII) genes and one nuclear (ITS2) gene were independently analyzed to determine their relationship with chromosome number. Five distinct hydrocarbon phenotypes were found, but these were only partly congruent with chromosome number and thus with purported species descriptions. Molecular and cuticular hydrocarbon data each indicate that Cryptocercus with a male karyotype of 2n=43 belong to at least two distinct, distantly related lineages. One 2n=43 lineage is sister group to the 2n=37 and 2n=39 clade, and has a unique hydrocarbon profile. The other 2n=43 lineage is sister group to the 2n=45 samples, and its cuticular hydrocarbons group with four samples of the 2n=45 lineage. The cuticular hydrocarbons of two additional 2n=45 samples diverge from this assemblage. Results indicate cuticular hydrocarbons and chromosome number have some degree of evolutionary independence; neither is completely reliable in delineating historical lineages. Our data provide support for the parallel model of chromosome evolution in the species complex.

Molecular characterization of Lma-p54, a new epicuticular surface protein in the cockroach Leucophaea maderae (Dictyoptera, oxyhaloinae).

The epicuticular surface protein Lma-p54 is imbedded in the "cuticular waxes" which cover the abdominal surface of the adult Leucophaea maderae. Natural Lma-p54 was purified and the complete cDNA sequence was determined by RT-PCR using primers based on Edman degradation fragments. Northern blot and in situ hybridization analyses showed that Lma-p54 was expressed in the adult abdominal epidermis and in the chemical sense organs of both sexes. Sequence alignment indicates that Lma-p54 is closely related to aspartic proteases (EC 3.4.23). However, there are critical amino acid substitutions at the level of the active site and, since no proteolytic activity was detected in the abdominal secretion, the protein is likely inactive. As an inactive aspartic protease, Lma-p54 is related to pregnancy-associated glycoproteins (PAGs) which still present a peptide-binding ability. According to recent experiments using whole tergal protein secretions, a role in intraspecific contact recognition was proposed for this surface protein.

Molecular characterization of a new adult male putative calycin specific to tergal aphrodisiac secretion in the cockroach Leucophaea maderae.

Lma-p18 is an epicuticular surface protein specific to the tergal gland aphrodisiac secretion of Leucophaea maderae adult males. Native Lma-p18 was purified and the complete cDNA sequence was determined by RT-PCR using primers based on Edman degradation fragments. Northern blot and in situ hybridization analyses showed that Lma-p18 is expressed exclusively in the anterior part of male tergal gland, which is exposed only during sexual behavior. Sequence analysis indicated that Lma-p18 belongs to the calycin superfamily and is very similar to Lma-p22, the first known male-specific tergal protein in L. maderae. Lma-p18 and Lma-p22 were proposed to bind different sexually attractive compounds as other calycins.

Production, regeneration and biochemical precursors of the major components of the defensive secretion of Eurycotis floridana (Dictyoptera, polyzosteriinae).

The defensive secretion of the cockroach Eurycotis floridana contains three main components, (E)-2-hexenal, (E)-2-hexenol and (E)-2-hexenoic acid, which represented about 98% of the organic phase. The quantity of the aldehyde, alcohol, and acid present in the defensive secretion increased rapidly for 60 days from the imaginal moult. Following artificial discharge, the males were able to regenerate their initial volume of secretion over a 30 day period. To investigate the possible routes of biosynthesis of the three components, E. floridana was injected with 14C-labeled fatty acids and acetate, and the incorporation of 14C into the three components were quantified 1, 6, and 24 h after milking. Our results revealed that oleic, linoleic, linolenic and palmitic acids, which constitute part of the fat body of the insect, were incorporated to the same degree into the three main components, but very slowly compared to acetate. Although it has not been possible to identify the exact route of aldehyde, alcohol and acid biosynthesis, our findings suggests that (E)-2-hexenal, (E)-2-hexenol and (E)-2-hexenoic acid are preferentially biosynthesized de novo from acetate.

cDNA cloning of an adult male putative lipocalin specific to tergal gland aphrodisiac secretion in an insect (Leucophaea maderae).

Lma-P22 is a cuticular surface protein specific to the tergal gland secretion of Leucophaea maderae adult males which is ingested by females just before copulation. The complete Lma-P22 cDNA sequence was determined by RT-PCR using primers based on Edman degradation fragments. The recombinant protein expressed in Escherichia coli was recognized by an anti-Lma-P22 antibody. Northern blot analysis indicates that the corresponding mRNA is transcribed only in the epidermis of male tergites. Sequence analysis indicated that Lma-P22 deduced protein belongs to the lipocalin family. Lipocalins are extracellular proteins which carry hydrophobic compounds and some of them can bind sexual pheromone in vertebrates. Lma-P22 is the first example of a lipocalin-like protein involved in insect sexual behavior.

Characterization of two male-specific polypeptides in the tergal glands secretions of the cockroach Leucophaea maderae (Dictyoptera, Blaberidae).

During the sexual behavior of cockroaches, the female mounts the courting male to feed on the proteinaceous secretion of the tergal glands. Polyacrylamide gel electrophoresis of male and female protein extracts after cuticle wiping revealed three major bands. Two of 18 and 22 kDa, named Lma-P18 and Lma-P22, are specific to the male tergal extracts. Moreover, Lma-P22 is only found in the male second tergite extracts. The third one of 54 kDa, named Lma-P54, is common to male and female extracts and could be considered as an ubiquitous surface protein. Several other minor proteins are also present on the body surface of adults of both sexes. Quantitation of the total protein amount of the male tergal gland secretion shows a progressive accumulation from adult ecdysis to sexual maturity. Western blot analysis using antibodies raised against Lma-P22 and Lma-P54 confirms that Lma-P22 is only secreted by the male second tergite glands. Immunohistolocalization demonstrates that these three major proteins are produced by class 3 glandular cells.

Male sex pheromone of cockroachEurycotis floridana (walker) (Blattidae, Polyzosteriinae): Role and composition of tergites 2 and 8 secretions.

InEurycotis floridana, the male calling behavior is associated with the exposition of epidermal glands located under tergites 2, 7, and 8. 4-Hydroxy-5-methyl-3(2H)-furanone and 4-hydroxy-2,5-dimethyl-3(2H)-furanone were recently identified as the specific components of tergite 7 secretion. Methylene chloride extracts of tergite 7 and its major compound 4-hydroxy-5-methyl-3(2H)-furanone attract the conspecific females at a distance. Methylene chloride extracts of tergite 8 are also attractive at a distance to the females, whereas extracts of tergite 2 had no effect on males and females. Our GC investigations showed the absence of specific compounds in tergite 2 secretions. The GC-MS analyses revealed that the male secretion of the gland under tergite 8 is mainly a mixture of (2R*, 3R*)-butanediol, 1-dodecanol and benzyl 2-hydroxybenzoate. These compounds were tested at different concentrations on their own, or as a mixture. Only (2R*, 3R*)-butanediol and 1-dodecanol were attractive for the females. Their functions, as components of the male sex pheromone, in addition with the two derivatives of the furanone are discussed.

Evidence for sex pheromones produced by males and females inBlatta orientalis (Dictyoptera, Blattidae).

Males and females ofBlatta orientalis produce a volatile sex pheromone attractive at a distance. The male initiates courtship behavior by adopting a calling posture while emitting his sex pheromone. He exposes the anterior region of his tergites by stretching his abdomen horizontally. Morphological observations show the existence of male tergal glands on the anterior region of tergites 1 to 8. Behavioral assays of females utilizing methylene chloride extracts of various male body parts reveal that extracts of the anterior region of tergites are highly attractive and induce more positive responses that any other body part. Once near the male, the attracted female opens widely her genital atrium thus exposing her atrial glands. Behavioral assays reveal that these atrial glands are certainly the site of production of the female sex pheromone.

Chemistry of pheromonal and defensive secretions in the nymphs and the adults ofDysdercus cingulatus Fabr. (Heteroptera, Pyrrhocoridae).

The exocrine secretions from the nymphs and the adults of both sexes inD. cingulatus were chemically investigated. Seven compounds were identified in the anterior glands, and eleven in the median dorsoabdominal glands of nymphs and adults of both sexes. Fifty-five compounds were identified in the defensive glands (34 in posterior dorsoabdominal glands ofnymphs and 21 in metathoracic glands of adults), and six in the sternal glandular epithelium of the males. The biological function of the glandular secretions and of their identified compounds were investigated and are discussed.

Chemistry of defensive secretions in nymphs and adults of fire bug,Pyrrhocoris apterus L. (Heteroptera, Pyrrhocoridae).

The defensive secretions from the nymphs and the adults of both sexes inP. apterus were chemically investigated. Forty components were identified from the nymphal posterior dorsoabdominal glands and 35 from the adult metathoracic glands of both sexes. Within the 43 identified chemicals, we found 23 aldehydes, five saturated hydrocarbons, five alcohols, three ketones, three lactones, two terpenes, one phenol and one ester. Thirteen of these compounds had never been reported within the Heteroptera. Whereas eight components are specific to the nymphs, methyl pentenal, (E)-2-hexenol, and heptadecanal are the only adult-specific components. The biological role of all the identified chemicals is almost unknown inP. apterus and is discussed comparatively with regard to other Heteroptera.

2-Methylthiazolidine and 4-ethylguaiacol, male sex pheromone components of the cockroachNauphoeta cinerea (dictyoptera, blaberidae): A reinvestigation.

InNauphoeta cinerea, male calling behavior is associated with sex pheromone release by the sternal glands. The male pheromone that attracts females from a distance is a mixture of 2-methylthiazolidine and 4-ethylguaiacol. It is active at very low concentrations, 0.05 and 0.01 ng, respectively. Two other compounds, 3-hydroxy-2-butanone and 2-methyl-2thiazoline, act at close range, keeping the female in the vicinity of the male. The function of the volatile pheromone and those of previously described contact pheromones are discussed in regard to their possible involvement in the establishment of male dominant-subordinate relationships.

Isolation and identification of 4,6,8-trimethyl-7,9-undecadien-5-ol, a female-specific compound, in tergal gland secretion ofCryptocercus punctulatus scudder (Dictyoptera: Cryptocercidae).

The secretion of the tergal glands ofCryptocercus punctulatus consists of a complex mixture of 27 compounds. Of this mixture, only one compound (compound B) is specific for females. By dissecting 200 tergal glands, 50 µg of pure compound B was collected by preparative GC; it was identified as (Z, E-4,6,8-trimethyl-7,9-undecadien-5-oI. Its functions as well as its absolute configuration still have to be determined.

Tergal glands of male and femaleCryptocercus punctulatus scudder (Dictyoptera: Cryptocercidae): Composition, sexual dimorphism, and geographic variation of secretion.

Males and females ofCryptocercus punctulatus possess tergal glands, but they differ in position, size, morphology, and secretion chemistry. Compound A (linalyl acetate) is the most abundant of the 21 compounds found only in the secretion of these glands. Compound B, 4,6,8-trimethyl-7,9-undecadien-5-ol, is specific to the tergal secretion of females.C. punctulatus lives only in the United States; its distribution is disjunct. Compound A is found in samples from the eastern population but is absent in samples from the western population. The amount of compound B per gland in samples from the western population is at least twice as high as in the samples from the eastern populations.

Genital sex pheromones of ixodid ticks: 1. Evidence of occurrence in anterior reproductive tract of American dog tick,Dermacentor variabilis (Say) (Acari: Ixodidae).

The occurrence of a genital sex pheromone in the anterior reproductive tract of partially fed femaleDermacentor variabilis was demonstrated by extraction and bioassay. A new type of bioassay, the "neutered" female assay, was developed to test the potency of extracts or chemically defined fractions to stimulate males to copulate. Electrophysiological tests confirmed the ability of males to detect the pheromone with sensilla on their cheliceral digits. Males of bothD. variabilis andD. andersoni exhibited neuronal excitation when stimulated with extracts of theD. variabilis reproductive tissues. The pheromone, which is soluble in methanol, was fractionated and found to contain at least two fractions that stimulated copulation by sexually excited males. Evidently, the pheromone is a mixture of two or more compounds. Histologic, ultrastructural, and histochemical studies suggest the vestibular vagina as the site of genital sex pheromone occurrence, presumably from secretions of the surrounding lobular accessory gland. The identity of the compounds that comprise the pheromone remains unknown.

Allomonal secretions in cockroaches.

We have analyzed the allomonal secretions in 10 species of cockroaches belonging to seven genera and made a detailed reanalysis of these secretions in three other species previously studied. Forty-three products were identified (quinones, phenols, acids, ketones, aldehydes, lactones, hydrocarbons, alcohols and various products). In many cases, the function of these secretions is unknown. We were able to test in the laboratory and also in natural conditions the different products identified, and we were able to test the reactions of several cockroaches when attacked by natural predators (beetles, lizards, toads, and bats). InEurycotis decipiens, the secretion of the sternal glands has a strong deterrent effect on the predators. InEublaberus distanti, the secretion of the glands associated with the second abdominal spiracle acts as an alarm pheromone. In several species ofPeriplaneta, the function of the sternal secretions is unknown. The components of these allomonal secretions are discussed.

Tergal modifications associated with abdominal glandular cells in the Blattaria.

Tergal abdominal modifications of 30 species of Blattaria (Dictyoptera) were studied by means of histological scanning electron microscopy techniques. Despite marked anatomical diversity of the glands, only a few basic types of cells are present. Male tergal glands which are involved in sexual behavior generally have glandular cells filled with electron transparent vacuoles (type 3a) and those with dense myeloid secretion (type 3b); in addition some have large cells without ducts, not in contact with the cuticle and surrounded by other cells (type 2). External setae, usually associated with these structures, are mechano-receptors or mechano-chemoreceptors. Glands not involved in courtship (e.g., defensive glands) usually have large glandular cells with a ductule that reaches the end apparatus secreted by the glandular cell itself (Type 3) but lack types 2, 3a, and 3b. Species which do not have distinctive tergal modifications may have concentrations of microscopic pores or openings associated with glandular cells on certain segments. The chemistry of the secretions produced by tergal glands is unknown for most species. This paper emphasizes the need for behavioral and biochemical studies to elucidate the biological significance of cockroach tergal glands.

[The development, structure and function of the mandibular glands of Blaberus craniifer burm. (Dictyoptera Blaberidae)]. / Les glandes mandibulaires de Blaberus craniifer burm. (Dictyoptera, Blaberidae) developpement, structure et fonctionnement

The mandibular glands of Blaberus craniifer are examined by histochemical, electrophoretic, thin-layer chromatography and electron microscopical techniques. These glands are known to secrete a volatile aggregative pheromone. The gregarious behaviour increases during insect development and is maximal in imagos. Each gland is composed of a bundle of secretory cells with efferent ductules which arise in a common duct. Secretory cells contain a myeloid secretion more abundant in imagos than in larval stages. Histochemical and electrophoretic criteria show that the myeloid product is made up of a mixture of glycoproteins. A lipidic component is also present in the secretion; its ultrastructural localization remains to be elucidated. Cytological features are in agreement with the gregarious behaviour of cockroaches. Detailed structure and functional interpretation are also discussed.