Ecology of an Indian grassland millipede Streptogonopus phipsoni (Diplopoda: Polydesmoidea)

Abstract

Each of stadia II‐VII and adults (stadia VIII) of Streptogonopus phipsoni (Pocock) can be distinguished by segment numbers, length, breadth and paired legs. Sexes are separate from stadium IV and sex ratios in immature stages were more or less 50% throughout the year, but high proportions of adult females are noted from June to September. High ratios of immature to adult were related to the breeding periods, from May to October, and in other months adults increased in proportion as a result of heavy mortality of immatures. Adults were aggregated in distribution from April to October while solitary individuals were common in other months of the year. Population density of S. phipsoni varied from 0.25 to 98 m‐2 on the soil surface and 1 to 11.75 m‐2 in the lower layer (0–7 cm deep). Biomass ranged from 12.25 to 2253 mg‐2 on the surface and 50.75 to 424.75 mg‐2 in the lower layer (0–7 cm deep). A positive and significant correlation was found between mean monthly population density and mean monthly rainfall. Streptogonopus phipsoni appears to complete its life cycle in one or two years

Anamorphosis in millipedes (Diplopoda)-the present state of knowledge with some developmental and phylogenetic considerations

“…The only other report of this kind known to us is that of Bhakat (1987, Bhakat et al, 1989 who recorded stadium I1 juveniles of Streptogonopusphipsoni as having seven leg-pairs. Bhakat (1987) noted that this observation is at variance with the findings of Bellairs et al (1983) who found the normal number of six leg-pairs in stadium I1 of S. phipsoni. Intraspecific variability is thus indicated.…”

Ecology of Chondromorpha kelaarti (Diplopoda, Polydesmida)

“…Aggregations in millipedes have been reported by several authors (Fryer, 1957;Toye, 1967;Blower, 1970;Lewis, 1971aLewis, , 1974Snider, 1984;Bhakat, 1987). The highly aggregated distribution pattern of C. kelaarti may indicate that its requirements are unevenly dispersed.…”

“…Sampling was made at fortnightly intervals from December 1985 to November 1986 and on every sampling data 8 samples each of 0.1 m2 were taken at random. The samples were then processed in the Laboratory as described by Bhakat (1987) and individuals were sorted according to their sex, size and maturity. During sampling, a metal quadrat (0.1 m2) with a sharp lower edge was driven into the ground to a depth of 8 cm and the contents of the sample placed in a plastic jar.…”

“…Lengths and breadths of different stadia were determined as described by Blower & Gabbutt (1964), Blower & Miller (1977) and Bhakat (1987). Each sample was weighed separately with an accuracy up to 0.01 mg for the estimation of biomass and each adult (male and female) was also weighed for determining size/ weight relationship.…”

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

“…Bhakat 1987Bhakat , 1989Lewis 1971) have been based on intensive hand-sampling of all life-stages. Pitfall trapping in the present study selectively captured adults, and the results do not allow conclusions to be drawn about life histories, breeding cycles or population densities.…”