DOI: 10.3897/asp.84.e186815

Authors: Qing Li, Gregory D. Edgecombe, Chao Jiang

Abstract: Abstract Hainanthereua albilineata gen. nov. et sp. nov. is described and illustrated based on specimens from Hainan Province, China. Morphological examination showed that these specimens belong to Thereuoneminae and share certain similarities with Thereuopodina Verhoeff, 1905. Phylogenetic reconstruction based on five genes (nuclear 18S and 28S rRNA, mitochondrial 12S and 16S rRNA, and cytochrome c oxidase subunit I) indicated that the specimens form a distinct and well-supported clade that is sister group to Thereuonema Verhoeff, 1904, so a new genus is accordingly established. Combining the evolutionary history and biogeographic framework of Thereuoneminae, this study revealed the evolutionary significance of Hainanthereua gen. nov. in the context of the Peninsular Indian Plate as a biotic ferry implicated in the origin of East and Southeast Asian lineages. Morphological similarities between Hainanthereua and Thereuopodina are symplesiomorphies of a clade that includes these two genera, Thereuonema and Thereuopoda Verhoeff, 1904.

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DOI: 10.3897/asp.83.e137316

Authors: Magdalena Rost-Roszkowska, Łukasz Chajec, Dalibor Stojanović, Dragan Antić

Abstract: The middle endodermal region of the digestive system (midgut) of arthropods is responsible for processes related to digestion but is also considered an organ participating in homeostasis maintenance. Therefore, many experimental studies, for example, related to the effect of various stressors on the organism, are conducted on the epithelium of this intestine. However, it is important to know the basic structure and ultrastructure of the midgut tissues. In myriapods (e.g., millipedes), the midgut has the form of a simple tube lined with a single layer of epithelium, surrounded by hepatic cells and visceral muscles. Considering the fact that millipedes can inhabit various terrestrial environments, feed on a variety of foods, and are important links in food chains, they can be considered good models for ecotoxicological studies. Thus, we selected eight species belonging to the family Julidae (order Julida) to investigate whether any distinct ground pattern for this organ appears within one millipede systematic group and whether it is possible to translate it into the general pattern of the midgut epithelium in millipedes: Leptoiulus sarajevensis (Verhoeff, 1898), Leptoiulus trilineatus (C. L. Koch, 1847), Cylindroiulus boleti (C. L. Koch, 1847), Megaphyllum bosniense (Verhoeff, 1897), Pachyiulus cattarensis (Latzel, 1884) and Pachyiulus hungaricus (Karsch, 1881) as representatives of the epigean fauna as well as Leucogeorgia longipes Verhoeff, 1930 and Leucogeorgia gioi Antić and Reip, 2020 as true cave-dwelling species. The study was performed using light and transmission electron microscopy. The results revealed a general pattern of all cells forming the midgut epithelium in Julidae, as well as the hepatic cells surrounding the midgut. Some small differences were observed, which are probably related to the type of food consumed.

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DOI: 10.3897/asp.82.e136751

Authors: Rong Chen, Yi Zhao, Sergei Golovatch, Wei-Xin Liu

Abstract: A taxonomic study of the genus Skleroprotopus Attems, 1901 from nine provinces in China was conducted utilizing morphological comparisons and molecular phylogenetic analyses. The results reveal thirteen new species, i.e. Skleroprotopus yutiantianae sp. nov., S. tiankeng sp. nov., S. megistus sp. nov., S. penglai sp. nov., S. longissimus sp. nov., S. genjudi sp. nov., S. laiyuanensis sp. nov., S. longiflagellatus sp. nov., S. change sp. nov., S. ampullaceus sp. nov., S. incisodentatus sp. nov., S. multistriatus sp. nov., and S. conicus sp. nov. This significantly enriches the diversity of Skleroprotopus in China, bringing it to a total of 18 species. With the exception of S. yutiantianae sp. nov., all these species were collected in caves. In terms of their degree of adaptation to the cave environment, the latter six species are presumed troglophiles, while the others are likely troglobites. DNA-barcoding based on the COI mitochondrial gene is documented for the first time in this genus. The specific p-distances between Skleroprotopus species range from 6.6–17.0%, while intraspecific p-distances are only 0.2–1.4%. Additionally, the morphological features of male leg-pair 1, the penis and leg-pair 7 are also discussed.

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DOI: 10.3897/asp.81.e100520

Authors: Leif Moritz, Antonio Parra-Gómez

Abstract: The millipede family Siphonorhinidae (order Siphonophorida) shows a scattered distribution in South Africa, Madagascar, India, Southeast Asia, and North America. So far, the family is unknown from South America, while species of Siphonophoridae, the second family of the order, are relatively abundant on the continent. However, not a single Siphonophorida is known from Chile. Here we describe the monotypic genus Notorhinus gen. nov. with N. floresi sp. nov. and record a second Notorhinus (undescribed) species, as first records of the order Siphonophorida in Chile and of the family Siphonorhinidae in South America. Notorhinus gen. nov. is distinct from the remaining Siphonorhinidae by the arrangement of the sensilla basiconica on the antennae and other somatic and sexual characters. However, it shows close morphological affinities to the North American genus Illacme Cook and Loomis 1928. In the Americas Siphonorhinidae were previously only known from California (USA), where they inhabit subterranean micro-habitats. The Chilean species was found under a piece of decaying wood in a small patch of fragmented native forest. Thus, the group shows a disjunct antitropical distribution in America at ca. 37° North and 38° South. They might be the relict of a once greater distribution, which persisted in these areas due to similar climatic conditions.

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DOI: 10.3897/asp.80.e86810

Authors: Antonio Parra-Gómez, Leonardo D. Fernández

Abstract: Research on the diversity and biogeography of Chilean millipedes represents a significant gap in knowledge. To reduce this gap we conducted a study: (1) to investigate the current state of knowledge of millipede diversity, and (2) to assess the pattern and causes underlying the latitudinal diversity gradient in Chilean millipedes. In Chile, 95 native millipede species have been recorded. However, rarefaction and extrapolation curves showed that increased sampling effort will reveal more species. An asymptotic estimate of diversity predicted that millipede diversity fluctuates between 125 and 197 species. The estimate, though, was based on a limited data set. Therefore, millipede diversity is probably higher than predicted. Chilean millipedes were categorized as micro-range endemics because they all have latitudinal ranges of less than 1,000 km (with 78% of species exhibiting latitudinal ranges of only ~222 km). Millipede species richness also exhibited a bell-shaped latitudinal diversity gradient, i.e. diversity peaks in the temperate climate of central Chile and decreases towards the arid and polar climates of northern and southern Chile. A multiple regression analysis revealed that this biogeographic pattern is shaped by environmental variables related to water availability, ambient energy inputs and climatic stability. These environmental variables are proxies for two of the five biogeographic hypotheses we tested in this study, i.e. the water-energy balance hypothesis and climatic stability hypothesis. Both hypotheses suggest that millipedes need stable, humid and warm climates to grow, survive and reproduce (niche conservatism). These climatic conditions are only found in central Chile, which is consistent with the diversity peak observed in that region.

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DOI: 10.3897/asp.79.e70002

Authors: Leif Moritz, Thomas Wesener

Abstract: Abstract The production of sticky threads from spinnerets is known from various myriapod groups including some representatives of the millipedes (Diplopoda). In Diplopoda the thread-producing glands are mostly seta-like and positioned terminally on the telson, and the secretion product is typically used to build molting chambers or egg sacs. So far, no such secretions or organs have been documented for the subgroup Pentazonia. Here we describe thread-producing glands from the species-poor Glomeridesmida. These putative spinning organs are single circular fields of small pores (spinning fields) positioned on the outer side of the tarsi of all walking legs of mature and juvenile individuals of both sexes. These pores are the openings of cuticular tubuli (conducting canals), which extend from the tarsus to an aggregation of cells, a putative gland, within the femur. In several specimens thin threads were observed to be extruded from the pores. The tarsal spinning fields are present in all 21 investigated Glomeridesmida morphospecies, including Termitodesmidae and Glomeridesmidae from South East Asia, the Indian subcontinent, Oceania, and South and Central America. These organs might constitute an apomorphic character of the Glomeridesmida, as similar organs are absent in other Myriapoda. The function of the extruded threads in Glomeridesmida remains speculative, because observations of living specimens of the group are almost non-existing. We suggest that the secretion might be used for defense, to build molting chambers or to secure tunnels burrowed in the substrate.

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DOI: 10.3897/asp.79.e67022

Authors: Magdalena Maria Rost-Roszkowska, Jitka Vilimová, Karel Tajovský, Vladimír Šustr, Anna Ostróżka, Florentyna Kaszuba

Abstract: Abstract The middle region of the digestive system of millipedes, the midgut, is responsible for all processes connected with digestion, but also takes part in homeostasis maintenance thanks to the ability to activate many mechanisms which neutralize changes occurring at different levels of the animal’s body. Numerous millipede species are treated as bioindicators of the natural environment and they are exposed to different stressors which originate from external environment. To obtain all data on the functioning of midgut of millipedes as the barrier against stressors, it is necessary to have a precise and general description of the midgut epithelium. Members from four millipede orders were selected for the studies: Polydesmus angustus (Polydesmida), Epibolus pulchripes (Spirobolida), Unciger transsilvanicus (Julida) and Glomeris tetrasticha (Glomerida). The structure and ultrastructure of their midgut epithelial cells (the digestive, secretory and regenerative cells) were documented using transmission electron microscopy and histochemical methods. The obtained results have been compared and discussed to previous ones, to present the general and structural organization of the midgut in Diplopoda. Our studies revealed that the ultrastructure of all cells which form the midgut epithelium in millipedes is general for all the species studied up to now and it resembles the cell ultrastructure observed in Chilopoda and Hexapoda, including the digestive, secretory and stem cells.

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