RESUMEN
The presence of morphological integration and modularity of the forcipular apparatus, despite its evolutionary significance, has not been analyzed in centipedes. This morphological structure has a crucial role in feeding and defense, thanks to its poisonous part (forcipules), which is important for catching the prey. The aims of our study were: i) to test the hypothesis of modularity of the forcipular apparatus in centipede Lithobius melanops; and ii) to investigate the influence of allometry on overall morphological integration in the aforementioned species using a geometric morphometric approach. The presence of fluctuating asymmetry was obtained by Procrustes ANOVA. Allometry was significant only for the symmetric component of the forcipular apparatus. The modularity hypothesis was not accepted, because the covariance coefficients for symmetric and asymmetric components were lower than 89.5% and 72.1% (respectively) of other RV coefficients obtained by a random contiguous partition of the forcipular apparatus. Results of the present study indicate that allometry does increase the level of morphological integration in the forcipular apparatus. According to our results, the forcipular coxosternite and forcipules could not be considered as separate modules; namely, they probably share similar developmental pathways and function in different forms of behavior and survival in L. melanops.
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Evolución Biológica , Quilópodos , AnimalesRESUMEN
Here we describe in detail the late post-embryonic development of the common European scolopendromorph centipede Cryptops parisi. Canonical variate analyses of two groups of external morphological characters, viz., cephalic capsule characters (head length, length of the anterior and posterior paramedian cephalic sutures) and coxopleuron surface characters (number of pores in the coxal pore-field, number of setae on the posterior coxopleuron edge, their number on the coxal pore-field, and their number posterior to the coxal pore-field) were conducted on a large sample of specimens collected from two localities in Serbia. Ten free-living stages are recognized: three pre-adult stages (adolescens I, II, and III) and seven adult stages (one maturus junior stage, four maturus, and two maturus senior stages). The fourth late post-embryonic stage is the first mature stage in both sexes. Sexual dimorphism in the aforementioned characters was not observed. Morphological variation of coxopleuron characters was more informative for the discrimination of developmental stages in Cryptops than the morphological variation of cephalic capsule characters.
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Artrópodos/crecimiento & desarrollo , Animales , Artrópodos/anatomía & histología , Femenino , Masculino , SerbiaRESUMEN
A review of the genus Typhloiulus Latzel, 1884 (Julida: Julidae) in the Dinaric region is given. Previously published and new faunistic records are provided for each species, together with notes for some of them. Four new species are described: T. clavatus sp. nov., T. gracilis sp. nov., T. opisthonodus sp. nov., and T. parvulus sp. nov., all from caves in Dalmatia and Herzegovina. In addition, we provide the first description of the male of T. insularis Strasser, 1938. Some taxonomic relationships among Typhloiulus species and biogeographical aspects (with distribution maps) of the genus are discussed.
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Artrópodos , Cuevas , Distribución Animal , Animales , Bosnia y Herzegovina , MasculinoRESUMEN
Cave animals live under highly constant ecological conditions and in permanent darkness, and many evolutionary adaptations of cave-dwellers have been triggered by their specific environment. A similar "cave effect" leading to pronounced chemical interactions under such conditions may be assumed, but the chemoecology of troglobionts is mostly unknown. We investigated the defensive chemistry of a largely cave-dwelling julid group, the controversial tribe "Typhloiulini", and we included some cave-dwelling and some endogean representatives. While chemical defense in juliform diplopods is known to be highly uniform, and mainly based on methyl- and methoxy-substituted benzoquinones, the defensive secretions of typhloiulines contained ethyl-benzoquinones and related compounds. Interestingly, ethyl-benzoquinones were found in some, but not all cave-dwelling typhloiulines, and some non-cave dwellers also contained these compounds. On the other hand, ethyl-benzoquinones were not detected in troglobiont nor in endogean typhloiuline outgroups. In order to explain the taxonomic pattern of ethyl-benzoquinone occurrence, and to unravel whether a cave-effect triggered ethyl-benzoquinone evolution, we classed the "Typhloiulini" investigated here within a phylogenetic framework of julid taxa, and traced the evolutionary history of ethyl-benzoquinones in typhloiulines in relation to cave-dwelling. The results indicated a cave-independent evolution of ethyl-substituted benzoquinones, indicating the absence of a "cave effect" on the secretions of troglobiont Typhloiulini. Ethyl-benzoquinones probably evolved early in an epi- or endogean ancestor of a clade including several, but not all Typhloiulus (basically comprising a taxonomic entity known as "Typhloiulus sensu stricto") and Serboiulus. Ethyl-benzoquinones are proposed as novel and valuable chemical characters for julid systematics.
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Artrópodos/química , Benzoquinonas/análisis , Cuevas , Ecosistema , Animales , Artrópodos/clasificación , Artrópodos/genética , Benzoquinonas/química , Benzoquinonas/metabolismo , Evolución Biológica , Cromatografía de Gases y Espectrometría de Masas , Filogenia , Extracción en Fase SólidaRESUMEN
As the fourth hydrophilous species of the genus Typhloiulus Latzel, 1884, the new species T. balcanicus Antic sp. nov. is described from two caves in the Stara Planina Mountains of Serbia. A brief discussion of the relationships between the new species and congeners with modified and unmodified mouthparts is presented, as well as short notes on the habitat of the new species and comments on other semiaquatic millipedes with modified mouthparts.
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Artrópodos , Animales , Cuevas , Ecosistema , SerbiaRESUMEN
A new species of Heterolatzelia Verhoeff, 1897, H. karlstrasseri sp. n., is described from the Datlo Cave in east Herzegovina. A brief discussion about the relationship between H. karlstrasseri sp. n. and H. durmitorensis Gulicka, 1968 and a distribution map of the family Heterolatzeliidae are presented.
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Artrópodos/clasificación , Distribución Animal , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Artrópodos/anatomía & histología , Artrópodos/crecimiento & desarrollo , Peninsula Balcánica , Tamaño Corporal , Ecosistema , Masculino , Tamaño de los ÓrganosRESUMEN
The geophilomorph centipede, Himantarium gabrielis, when disturbed, discharges a viscous and proteinaceous secretion from the sternal glands. This exudate was found by gas chromatography-mass spectrometry, liquid chromatography-high resolution mass spectrometry, liquid chromatography-mass spectrometry-mass spectrometry and NMR analyses to be composed of hydrogen cyanide, benzaldehyde, benzoyl nitrile, benzyl nitrile, mandelonitrile, mandelonitrile benzoate, 3,7,6O-trimethylguanine (himantarine), farnesyl 2,3-dihydrofarnesoate and farnesyl farnesoate. This is the first report on the presence of benzyl nitrile and mandelonitrile benzoate in secreted substances from centipedes. Farnesyl 2,3-dihydrofarnesoate is a new compound, while himantarine and farnesyl farnesoate were not known as natural products. A post-secretion release of hydrogen cyanide by reaction of mandelonitrile and benzoyl nitrile was observed by NMR, and hydrogen cyanide signals were completely assigned. In addition, a protein component of the secretion was analysed by electrophoresis which revealed the presence of a major 55 kDa protein. Analyses of the defensive exudates of other geophilomorph families should produce further chemical surprises.