The sexually reproducing stick insects Bacillus rossius and B. grandii are sharply differentiated in terms of allozyme gene alleles; B. atticus is a polyclonal automictic parthenogen sister to B. grandii grandii. Although well differentiated for coding genes, these hybridize to produce diploid (B. whitei=rossius/grandii) or triploid (B. lynceorum=rossius/grandii/atticus) clonal forms which reproduce apomictically. Allozyme analyses of unisexual Bacillus clearly establish their relationships from bisexual ancestor species as does the existence in all of them of several clones (especially in B. atticus) whose egg maturation allows regular recombination to occur. Bacillus taxa share the Bag320 satellite DNA family within different reproductive frameworks, allowing satellite variant homogenization to be uncoupled from fixation. The nested analysis of monomers reveals different patterns of sequence diversity: sexual reproduction includes both homogenization and variant fixation, whereas the slowing of molecular turnover processes and the absence of syngamy in the parthenogens realizes a similar range of sequence diversity at the level of the individual and supra‐individual, but with no fixation. On the other hand, the actual values of sequence diversity appear mostly linked to species traits – range size, copy number of repeats, number of hybrid crosses – and possibly transposon activity, rather than to the reproductive mode. In addition, the mitochondrial genome reveals a comparable level of cox2 sequence variability in sexual and parthenogenetic taxa, thus adding to clonal variability. From Bacillus and other stick insect complexes, an overall picture of genomic diversification of parthenogens is therefore beginning to emerge. To define those animals that reproduce by non‐canonical sexual modes (i.e. parthenogenesis, hybridogenesis), but make use of egg and meiotic mechanisms, the term meta‐sexual is proposed. © 2003 The Linnean Society of London. Biological Journal of the Linnean Society, 2003, 79, 137–150.

Sixty-six hirsute women were randomized and treated with 1) flutamide (n = 15), 250 mg/day; 2) finasteride (n = 15), 5 mg/day; 3) ketoconazole (n = 16), 300 mg/day; and 4) ethinyl estradiol (EE)-cyproterone acetate (CPA; n = 20), 0.01 mg EE/day for the first week, 0.02 mg EE/day for the second week, and 0.01 mg EE/day for the third week, followed by a pause of 7 days, then 12.5 mg CPA/day added during the first 10 days of every month for 12 months. Hirsutism was evaluated by the Ferriman-Gallwey score, and hair diameter and hair growth rate were determined by a special image analysis processor in basal conditions and after 90, 180, 270, and 360 days of treatment. All treatments produced a significant decrease in the hirsutism score, hair diameter, and daily hair growth rate: flutamide, -55 +/- 13%, -21 +/- 14%, and -37 +/- 18%; finasteride, -44 +/- 13%, -16 +/- 12%, and -27 +/- 14%; ketoconazole, -53 +/- 18%, -14 +/- 12%, and -30 +/- 21%; and EE-CPA, -60 +/- 18%, -20 +/- 11%, and -28 +/- 21%. Some differences existed among treatments with regard to effectiveness; EE-CPA and flutamide seem to be the most efficacious in improving hirsutism. For the hirsutism score, a greater decrease was seen with EE-CPA (-60 +/- 18%) than with finasteride (-44 +/- 13%; P < 0.01) and a greater decrease was seen with flutamide (-58 +/- 18%) than with finasteride (-44 +/- 13%; P < 0.05). Flutamide is the fastest in decreasing hair diameter; EE-CPA is the fastest in slowing down hair growth, even though at the end of the treatment there was a significant difference between flutamide and finasteride only (-41 +/- 18% vs. -27 +/- 14%; P < 0.05). Flutamide, ketoconazole, and EE-CPA induced a significant decrease in total and free testosterone, 5alpha-dihydrotestosterone, dehydroepiandrosterone, dehydroepiandrosterone sulfate, and androstenedione plasma levels. During the EE-CPA treatment, gonadotropins were suppressed, and the sex hormone-binding globulin level increased. Finasteride induced a decrease in dehydroepiandrosterone sulfate and 5alpha-dihydrotestosterone and an increase in testosterone levels. Very few side-effects were observed during treatment with low doses of flutamide, EE-CPA, and particularly finasteride. Flutamide induced a decrease whereas EE-CPA induced an increase in triglycerides and cholesterol, showing higher values within the normal range. Ketoconazole induced several side-effects and complications, and several people dropped out of the study. Despite different modalities of action and significantly different effects on androgen levels, low doses of flutamide, finasteride, and EE-CPA constitute very satisfactory alternative therapeutic regimens in the treatment of hirsutism.

The increasing number of recognized hybrid unisexual complexes among invertebrate and vertebrate animals has promoted investigations about their composition and origin. Morphological, karyological and genetic (protein and DNA) analyses clearly show that, owing to their persistence and incomplete reproductive isolation from ancestors, several all-female complexes are much more diversified than generally assumed and that they may also have an evolutionary role. Here the case of the stick-insects of the genus Bacillus is reported in some detail. This holomediterranean genus comprises three well differentiated species that in Sicily have hybridized repeatedly. The Bacillus mate-recognition system has not followed the species-specific differentiation of the allozyme-coding loci, allowing interspecific crosses to occur in areas of species sympatry with the production of two hybridogens, a corresponding allodiploid parthenogen and a trihybrid triploid parthenogenetic species. Hybridogenetic females eliminate the paternal haploset (grandii) while passing the unassorted rossius hemiclone to offspring, which will be again of F, hybrid structure through a real fertilization by host male sperm. The polyspermic eggs of the hybridogens can also produce full-paternal fertile progeny of both sexes (androgenetics), when mixis occurs between two sperm heads. The parthenogenetic mechanism of the corresponding hybrid B. whitei is very similar to the hybridogenetic one, excepting the automictic re-use of the segregated grandii haploset; therefore B. whitei offspring clonally maintain the maternal hybrid structure. The trihybrid B. lynceorum produces clonal descendants through an apomictic mechanism undergoing two seemingly normal meiotic divisions. Each Bacillus hybrid actually realizes a different egg maturation process; however, the three share one important feature: an intrameiotic DNA extra-doubling, leading to the formation of four-stranded chromosomes, and enabling the meiotic system to produce balanced gametes even under different ploidy level and hybrid structure. The extra-round of DNA synthesis seems to be triggered by the hybrid condition impairing the synaptic process. Also the parthenogenetic B. whitei produces androgenetics and it is even capable of incorporating a third genome into its automictic but clonal eggs, following fertilization by B. grandii or B. rossius males with the production of fertile «synthetic» triploids. These findings are evidence of clonal unisexuals reproductively interacting with related bisexuals and also suggest that evolutionary pathways have been undertaken by Bacillus. Also other unisexual complexes seem to have undergone similar microevolutionary steps and their reproductive traits and persistence, longer than commonly assumed, make increasingly difficult to think of the whole of unisexuals as «dead ends» or «blind alleys».

The worldwide distributed genus Monochamus Megerle, 1821 (Coleoptera Cerambicydae) comprises beetles that may become pests of economic importance in conifer stands in the Nearctic and Palearctic Regions. Besides direct damage due to the larval tunnelling habits, they have also been recognized as main vectors of the phytoparasitic nematode Bursaphelenchus xylophilus (Steiner & Buhrer, 1934) (Nematoda Aphelenchoididae). We analysed the complete mitochondrial cytochrome oxidase I gene and a fragment of the small subunit RNA gene sequences (1536 base pairs) in the five European species. These are: Monochamus galloprovincialis (Olivier, 1795), morphologically distinguished in two subspecies M. galloprovincialis galloprovincialis (Olivier, 1795) and M. galloprovincialis pistor (Germar, 1818); Monochamus sutor (Linneus 1758); Monochamus saltuarius (Gebler 1830); Monochamus sartor (Fabricius, 1787) and Monochamus urussovi (Fischer, 1806). For appropriate comparisons, also the Asiatic Monochamus alternatus Hope, 1842 and a Japanese M. saltuarius sample have been analysed. Both genes show an absolute identity between the two subspecies of M. galloprovincialis and a strong affinity between M. sartor and M. urussovi: the morphological subdivisions of the former taxon in two subspecies and of the latter in two entities of specific level are therefore not supported genetically. On the other hand, the Italian and the Japanese samples of M. saltuarius always cluster together in all trees, and for the remaining taxa, no doubt about their rank of specific differentiation emerges from present analyses. From a phyletic point of view, tree topology indicates the Japanese M. alternatus as the most differentiated taxon and the Euroasiatic M. saltuarius as basal to all other strictly European entities. Chromosome analyses show that the diploid autosomal complement ranges from 18 in M. saltuarius to 20 in M. galloprovincialis, and 22 in M. sartor, but a XX-Xy p sex determining system is shared by all analysed taxa. The M. saltuarius karyotype appears as the most primitive from which the others may be derived through Robertsonian fissions. Karyological data therefore agree with molecular analyses in indicating a basal position of Euroasiatic M. saltuarius with respect to the group of European Monochamus taxa; among these, M. galloprovincialis and M. sartor represent two clearly diverging evolutionary units. Furthermore, karyotype analyses substantiate molecular conclusions about the identity between M. galloprovincialis galloprovincialis and M. galloprovincialis pistor.

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In animals, some general features of centrosome dynamics and inheritance have been widely recognized. The most acknowledged model assigns to sperm the contribution of a centriole to the fertilized egg, which in turn provides the pericentriolar materials, including gamma-tubulin, recruiting them from the cytoplasm: the main zygote microtubule organizing center (MTOC) is thus reconstituted to organize first the spermaster and then the full first embryonic spindle. Obviously the model cannot apply to parthenogenetic systems, which actually rely on egg components alone. In stick insects of the Bacillus genus, the spindle of both somatic and germ cells is clearly anastral, therefore we have been investigating their centrosome in sexual and parthenogenetic taxa by analyzing its component dynamics and transmission through the use of monoclonal beta- and gamma-tubulin antibodies and transmission electron microscopy (TEM). It has been shown that in sexually reproducing species the spermatozoon does not contribute the centriole, so that the egg wholly provides the MTOC and the ensuing anastral spindle of the embryo: MTs appear to derive from pronuclear chromatin surroundings and no asters are observed. The parthenogenetic embryo development is the same as the sexual one if syngamy is excepted. The parthenogenetic mechanism realized by these panoistic insects appears to differ from that observed in the meroistic hymenopteran and drosophilid species, where the embryo spindle derives from asters formed in the egg cortex. In stick insects, the lack of sperm contribution to embryonic centrosome appears to be a major trait accounting for the widespread occurrence of facultative and obligate parthenogenesis within the order.

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The family Cichlidae constitutes most of the freshwater fish fauna of South America; its taxonomy is at present mainly based on morphological characters. Here, relationships among seven Cichlasomatini species have been investigated by studying their karyotype structure and by sequencing a 520 bp fragment of the mitochondrial 16S gene. Molecular data sets point to a high affinity of Cichlasoma amazonarum with Aequidens sensu stricto group, in particular with Aequidens tetramerus. Aequidens never form a single monophyletic clade: molecular trees group together ÔAequidens pulcherÕ and ÔAequidens rivulatusÕ and suggest their close relationship with Bujurquina and Laetacara, rather than with the A. sensu stricto group. Both molecular and karyotypic data confirm that Cleithracara maronii belongs to a distinct clade, thus supporting its generic differentiation based on morphological characters. Chromosome number, karyotype structure and molecular data suggest that Laetacara dorsigera is related to Bujurquina vittata and confirm their generic level of differentiation. From a cytotaxonomic point of view, a karyotype of 2n ¼ 48 with most acrocentric or subacrocentric chromosomes could be the ancestral one from which the others might have derived.