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The first new fossil pill millipede, order Glomerida, description in more than 150 years is based on two specimens, one male and one female, found in Baltic amber. Both specimens were studied with light- and micro-CT technology, allowing a detailed reconstruction of the posterior telopods and numerous other morphological characters. Based on these characters, the specimens can be securely placed in the megadiverse, mainly Asiatic genus Hyleoglomeris Verhoeff, 1910 as a new species, Hyleoglomeris groehni n. sp. The species H. groehni n. sp. is the oldest and only known fossil member of the Glomerida that is sufficiently described to allow for placement in a family or genus. The discovery of a fossil Hyleoglomeris in Baltic amber has biogeographic implications as the genus is now speciose in Asia, with the nearest relatives found in the Caucasus and some caves in Serbia and Greece. With the discovery of a fossil European Hyleoglomeris species, the cave Hyleoglomeris species are interpreted as relicts, surviving underground as living witnesses of a different time when Hyleoglomeris was still extant in Europe. Other cave Glomerida in Europe, as well as morphologically aberrant pill millipede species endemic to the Canary Islands, should be checked for potential placement in Hyleoglomeris.

The pill millipedes of the order Glomerida are a moderately diverse group with a classical Holarctic distribution pattern. Their classification is based on a typological system utilizing mainly a single character complex, the male telopods. In order to infer the apomorphies of the Glomerida, to elucidate its position in the Pentazonia, and to test the monophyly of its families and subfamilies, we conduct the first phylogenetic analysis of the order. To provide additional characters, we comparatively analyze the mandible using scanning electron microscopy. The final character matrix consists of 69 characters (11 mandible characters) and incorporates 22 species from 20 of the 34 pill millipede genera, representing all families and subfamilies, except the monotypic Mauriesiinae. Two species from each of the two other Pentazonian orders Sphaerotheriida and Glomeridesmida, as well as two Spirobolida, are included as outgroup taxa. The Glomerida are recovered as monophyletic and are supported by five apomorphies. Within the Pentazonia, the Glomeridesmida are recovered as the sister group to the classical Oniscomorpha (Sphaerotheriida + Glomerida) with weak support. The analysis provides little resolution within the Glomerida, resulting in numerous polytomies. Further morphological characters and/or the addition of molecular analyses are needed to produce a robust phylogenetic classification of the Glomerida.

The pill millipede species Glomeris aurita Koch, 1847 remained of relative unknown origin and appearance until its recent rediscovery in samples from the Bergamasque Alps, northern Italy. In order to provide an integrative redescription and accurate identification of the high-altitude microendemic G. aurita, COI barcode sequences from three individuals coming from two different localities were obtained. These sequences are compared with those of the syntopic endemic G. oblongoguttata Verhoeff, 1894, the widespread black morph of G. romana Verhoeff, 1900, as well as several widespread species including G. marginata Villers, 1789, G. connexa Koch, 1847, and G. klugii Brandt, 1833, which have rare colour morphs that exhibit some similarity to G. aurita. To rule-out any identity confusion of G. aurita with other high-altitude or little-known Italian Glomeris, specimens of G. transalpina Koch, 1836, G. oropensis Verhoeff, 1934, and G. primordialis Verhoeff, 1932 were also added to the dataset. Altogether, 24 sequences were compared. Morphologically, the specimens of G. aurita were studied utilizing scanning electron microscopy as well as non-invasive micro-CT technology. The distribution of both Bergamasque endemics, G. aurita and G. oblongoguttata, could be mapped and compared utilizing samples from the Museo civico di Scienze Naturali di Bergamo, as well as photographic evidence from an Italian naturalist forum. G. aurita has a very short active period and is the first known pill millipede species restricted to mountain tops and cold places, possibly representing a Nunatak survivor.

SUMMARY All trunk segments in the pill millipede Glomeris marginata (Myriapoda: Diplopoda) are initially patterned genetically, (as visualized by the embryonic expression pattern of the even-skipped gene) and formed morphologically, (as visualized by 4-6-diamidin-2-phenylindol stained embryos) in a single segmental period. In addition, formation of every nascent trunk segment concerns ventral as well as dorsal segmental units. Only after the formation of the nascent posterior trunk segments, the dorsal segmental units of two adjacent segments fuse to form a single dorsal segmental unit that subsequently covers two ventral leg-bearing segmental units. The formation of a diplosegmental unit, or in short a diplosegment, is thus the result of dorsal fusion of embryonic tissue and not the result of any splitting-process or fusion of dorsal tergites. The new data also argue against heterochrony as a primary causative factor for the formation of the diplosegments during the formation of dorsal versus ventral segmental units. Furthermore, no evidence was found supporting the hypothesis that anterior trunk segments in diplopods represent degenerate diplosegments. Two possible scenarios arise from the ontogenetic data presented here, whether this represents an ancestral feature of the diplopods, or alternatively if they represent an isolated case only found in Glomeris (and close relatives). If the former is the case, my work may provide an impressive example of Haeckel's recapitulation theory.

Specimens of the North American glomerid millipede Onomeris sinuata (Loomis, 1943) were collected at the type locality in Alabama, USA, and maintained briefly in the laboratory in native leaf litter. The millipedes could not be induced to produce defensive secretions by rough handling, tapping, squeezing or leg-pinching. Four specimens were extracted in methanol and the extract analyzed using gas chroma-tography/mass spectroscopy. The analysis revealed the alkaloids glomerin and homoglomerin, previously reported as components in the defensive secretion of the European glomerid Glomeris marginata (Villers, 1789). This report is only the second for the occurrence of quinazolinone alkaloids in animals. Keywords Onomeris sinuata , Glomeris marginata , quinazolinone alkaloids, Alabama, USA Introduction Nearly simultaneously in 1966, Schildknecht et al. (1966)and Meinwald et al. (1966) announced the discovery of two quinazolinone alkaloids in the defensive secre-tion of the European millipede Glomeris marginata

The complete mitochondrial genome (mitogenome) of the millipede Sphaerotheriidae sp. has been studied. The genome is 14,970 bp long and contains the typical complement of 13 protein-coding genes, 22 transfer RNA genes, and 2 ribosomal RNA genes. Gene order in Sphaerotheriidae sp. mitogenome is assumed to represent the myriapod ground pattern, which is shared by myriapod-chelicerate clade.

The body of arthropods is subdivided in serially homologous units, the so-called segments. In many arthropods, ventral and dorsal segmental tissue typically is aligned in parallel, but is dependent on different genetic inputs. In the pill millipede Glomeris marginata (Myriapoda: Diplopoda), ventral and dorsal segmental patterning is clearly decoupled providing an excellent model for the investigation of ventral versus dorsal segmentation mechanisms. This paper reports on the finding of a single embryo that lacks dorsal segmental and extraembryonic tissue. Ventral derivatives, however, are widely developed normally. This suggests that ventral and dorsal tissue is not only patterned differently, as shown previously, but also that ventral tissue can develop (or at least persist) independently from dorsal tissue. It also suggests a correlation of dorsal segmentation and function of the extraembryonic tissue. This assumed correlation may involve the guidance of the two dorsal hemispheres of the developing embryo dorsally, or that formation and/or maintenance of extraembryonic tissue depends on the input of dorsal segmental tissue. Whether the observed abnormalities are caused by mutation or are the result of otherwise disturbed early development is unclear.

What is a segment? In a thoughtful Perspective, [Minelli][1] explores segmentation during development of the pill millipede, and in so doing challenges prevailing views of what constitutes a segment. [1]: http://www.sciencemag.org/cgi/content/full/306/5702/1693