Patterns in pitfall captures of millipedes (Diplopoda: Polydesmida: Paradoxosomatidae) at coastal heathland sites in Tasmania

Abstract

The millipede by-catch from a 1986-88 spider survey in Tasmanian coastal heathland was tallied by species, sex and life-stage. Two species of paradoxosomatid Polydesmida, Notodesmus scotius Chamberlin, 1920 and Pogonosternum sp., made up 99.8% of the pitfall captures. The N. scotius catch (9754 individuals) was 80% adult (stadium VIII) and peaked in October-December with only 23 captures in July-September. The Pogonosternum sp. catch (116 individuals) was 91% adult and peaked in September, with 40% of all captures in July-September. These results, together with field observations, indicate that pitfall trapping mainly captured adults wandering during the mating season, and that mating seasons for the two species did not coincide. The Pogonosternum sp. captures were tightly clustered in space, showing that pitfall trapping can be an unreliable method for estimating millipede abundance unless the fine-scale spatial patterning of target species is known in advance. A third paradoxosomatid species known to be present near the survey sites, Dicranogonus sp., did not appear in any of the 938 pitfall samples containing millipedes. The overwhelming dominance of paradoxosomatid Polydesmida in heathland is in marked contrast to the dominance of dalodesmid Polydesmida in forest habitats in Tasmania.

The Australian millipede Dicranogonus pix Jeekel, 1982 (Diplopoda, Polydesmida, Paradoxosomatidae): a species with and without paranota

“…The sampling was carried out by T.B. Churchill, who trapped paradoxosomatids (as by-catch) in three 9 × 9 m pitfall arrays (nine evenly spaced traps per array) located at each of four 90 × 90 m sampling sites, with the traps emptied once a month for 14 months (Mesibov and Churchill 2003). The traps yielded 9754 specimens of Notodesmus scotius and 116 specimens of an undescribed Pogonosternum species.…”

“…I am not certain whether he was referring to the Furneaux Group, which is politically part of Tasmania, or to the northeast Tasmanian mainland, from which I had earlier reported the presence of Dicranogonus (Mesibov and Churchill 2003). …”

Revision of the Australian millipede genus Pogonosternum Jeekel, 1965, with descriptions of two new species (Diplopoda, Polydesmida, Paradoxosomatidae)

“…nov. in Kosciuszko National Park) and mostly inhabits forests, but P. jeekeli Decker, sp. nov. can also be found in coastal heathland in northeastern Tasmania (Mesibov & Churchill 2003), whereas P. jeekeli sp. nov. and P. montanum sp.…”

Preliminary data on centipedes (Chilopoda: Scolopendromorpha and Scutigeromorpha) in Ta Xua natural reserve, Son La Province, Vietnam

“…Mẫu được thu vào tháng 5 và 11 năm 2017. Thu mẫu định tính bằng nhiều cách khác nhau như lật đá, vạch thảm mục, đào đất và bằng phương pháp bẫy đất Barber của Mesibov & Churchill (2003). Thu mẫu định lượng bằng phương pháp rây đất trong các ô 50 cm × 50 cm của Ghiliarov (1976) ở các sinh cảnh rừng cây gỗ, rừng tre nứa, rừng hỗn giao, mỗi tuyến thu 15 ô/sinh cảnh, lặp lại sinh cảnh ở 4 tuyến thu mẫu.…”