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Two species of stick insects are currently known to be present in the Macaronesian archipelagos: Clonopsis gallica (Charpentier) (Phasmatodea: Bacillidae) on the Canary Islands and in the Azores and Carausius morosus (Sinéty) (Phasmatidae) in the Azores. Here, we provide the first reliable records of the presence and distribution of C. gallica and C. morosus on Madeira Island. Egg and adult stages are briefly described along with some notes on the life history of these species in captivity. Data on islandwide distribution are based on specimens donated by the public in response to an article published in a daily newspaper. This method of data collection raised great popular interest in stick insects. The role of newspapers as a means of communicating awareness in biodiversity issues is discussed.

SUMMARYKaryotypes of three species of Clonopsis and of various populations of Leptynia hispanica and L. attenuata complexes were analyzed. The taxonomic status of the latter complexes is still uncertain. These genera include bisexual and parthenogenetic polyploid species and populations. The chromosomal numbers are: 2n = 32 in bisexual C. algerica, 2n = 22 in bisexual C. maroccana, 3n = 54 in telytokous C. gallica, 2n = 38 in bisexual Leptynia hispanica, 3n = 57 in telytokous triploid populations of L. hispanica, 4n = 76 in telytokous tetraploid populations of the same complex, 2n = 36 in a bisexual taxon of L. attenuata complex, 2n = 38 in an other bisexual taxon and 4n = 76 in a parthenogenetic tetraploid taxon of the same complex. All the karyotypes are described. It is postulated that pericentric inversions and centric fusions have played a relevant role in chromosomal evolution of these genera. Because hybridization is the more frequent mode of speciation in these stick-insects, the polyploidy, conne...

Eggs of 6 Clonopsis gallica (Phasmatodea: Bacillidae) populations have been investigated by means of scanning electron microscopy (SEM) to detect intraspecific differences. Two main chorionic patterns have been observed: type 1 is common to 5 populations, while type 2 is found in the Motril (South Spain) sample. Type-2 sculpturing differs from type-1 in the absence of prominences on the operculum; and hemispheric, isolated mamelons replace the smooth and diffuse prominences of the common pattern on the egg capsule. This suggests that a considerable degree of difference exists in the South Spanish C. gallica . In the 5 type-1 populations, only minor and partially overlapping differences in the opercular pattern have been detected, so that the existence of subspecific taxa is very unlikely among them. Therefore, the Calabrian subspecies C. gallica affinis does not appear to be tenable. This is the 1st report on egg interpopulation differences in the Phasmatodea. These findings suggest further field search, along with karyological and gene-enzyme system analysis, within the C. gallica complex.

The scanning electron microscope morphology and the amino acid composition of the egg capsules of two Lonchodini, Lonchodes pterodactylus and Carausius morosus , are reported. In both species, the egg shows a structural organization common to all Phasmatodea so far investigated. Many details appear to be similar in the two species, such as the egg capsule tubercular sculpturing, the general features of the micropylar plate, and the presence of a well-developed opercular capitulum. These common characteristics fully support the inclusion of these two species within the same tribe. However, differences in the opercular sculpturing patterns, capitulum shape and implantation, micropylar cup conformation, the presence of tubercule-less pits on the egg capsule, and the polar mound in L. pterodactylus , indicate not only specific differences, but also at the generic level. Egg chorion characteristics therefore appear, to be of high taxonomic value in the Phasmatodea. From our analysis, it appears that the frequent anomalies of the micropylar plate in C. morosus are not directly related to the internal abdominal pressure in the female, as formerly suggested, but rather to ovariolar disturbances due to intersexuality. The chemical information obtained from amino acid analysis of the egg shell of the two species has confirmed a high glycine content, a stable quantity of serine, and trace amounts of cystine and methionine, and also showed a marked difference in tyrosine, when compared with the bacilline, Clonopsis gallica . The amino acid composition of the stick insect egg shell suggests that its proteins resemble silk proteins. Thus, the egg morphology at scanning electron microscope level and the amino acid composition data contribute to both ootaxonomy and better understanding of the phylogeny of the order.

The scanning electron microscope morphology and the amino acid composition of the egg capsule of the stick insect Clonopsis gallica have been studied. The egg capsule shows an irregular but characteristic pattern of rounded tubercules, which at higher magnifications reveal a still more detailed sculpturing. The micropylar plate shows specific structural characters, including a shallow square micropylar cup without micropylar orifices; ovariolar eggs, however, show a number (from 3 to 5) of wide, open micropyles. The opeculum does not possess the capitulum nor the pseudocapitulum, but among the prominent tubercules of the central area some aeropyles are present. The thick 3-layered chorion has a uniformly smooth internal surface; the spongy submicropylar plate possesses a tubule connecting the chorion to the vitelline membrane. The amino acid composition has revealed that glycine is the most common residue (33%), followed by serine and alanine (about 10% each), with traces of cystine and methionine. SEM features specifically identify the egg of C. gallica but also reveal some genuine similarities with the egg of B. rossius. The meaning of the existence of the micropylar orifices during egg development has been discussed. The amino acid composition is a new datum for the Cheleutoptera and it has been compared with that of insects having an orthopteroid structure. In particular, the high glycine content in C. gallica egg shell suggests a certain resemblance with the species of 5 families of Tettigonioidea, whilst there are definite differences with species of Gryllidae and Acrididae. Thus, the egg morphology and amino acid composition data can be utilized as aids in understanding the phylogeny and egg physiology in several insect orders.

Bergmann’s rule states that organisms at higher latitudes should be larger and thicker than those closer to the equator to better conserve heat, and Allen’s rule states that they will have shorter and thicker limbs at higher latitudes. Alternative explanations for latitudinal size clines include plant productivity and seasonality. The rules generally hold in endotherms, but in insects different species within the same genus can respond to latitude in unpredictable ways. We present the first biogeographical analysis of these rules in stick insects (order Phasmatodea), using four European species. Their long and thin bauplan makes the Phasmatodea ideal for ecomorphological studies of body length, which could identify the evolutionary drivers of their remarkable size range (including the world’s longest insects). Using preserved specimens from collections across Europe; body segment and limb measurements were taken for both genders of the species Bacillus rossius, Clonopsis gallica, Leptynia attenuata, and Pijnackeria hispanica. Lengths and volumetric features were compared to latitude as well as annual mean temperature, net primary productivity, and annual growing degree days, using weighted linear regressions and ANOVA analyses. At lower latitudes / higher temperatures, B. rossius and L. attenuata had longer limbs [Allen clines] and were larger bodied and/or longer [converse-Bergmann clines], while the other species did not show latitudinal clines per se. This matches what was predicted based on closely related insects and the presence of large Phasmatodea in the tropics, but violates the temperature-size rule. Most variation in size could be attributed to temperature, but untested factors could also play a role Whether these ecogeographic rules hold true for tropical Phasmatodea and whether genetics or environment play are more important in determining adult length are topics for future research.