Echiniscus blumi Richters 1903

Guil, Noemí, 2008, New records and within-species variability of Iberian tardigrades (Tardigrada), with comments on the species from the Echiniscus blumi-canadensis series, Zootaxa 1757, pp. 1-30 : 7

Echiniscus blumi Richters 1903

I have identified 1,302 specimens from all kinds of samples collected. Several morphotypes of Echiniscus blumi were identified in this study ( Fig. 2 ). The typical morphotype of this species (with lateral filaments at positions B, C and D; Table 4 ) ( Ramazzotti & Maucci 1983) was observed in 84% of all the specimens examined, while 7 morphotypes were found to represent less than 15% each as follows ( Fig. 2 ): (i) 14% of the specimens lacked a lateral filament at position B, (ii) 0.8% lacked a lateral filament at position D, (iii) 0.1% lacked lateral filaments at positions B and C, (iv) 0.08% had no filaments at positions C and D, (v) 0.08% lacked dorsal spines at position D, (vi) 0.4% lacked filaments at positions B and D and (vii) 0.5% lacked filaments at position C. Different morphotypes appear mixed within the same sample. Juvenile specimens, those with only two claws per leg, showed dorsal spines instead of dorsal filaments at position B. I recognized three sizes of cuticle sculptures with the same design (i.e., blumi type (Ramazzotti & Maucci 1983)): large, normal and small (comparing individuals of similar body length). Besides, several specimens showed two spurs at the base of the external claws of the fourth pair of legs while the remainder had only one spur. Mean body size was 507 μm (SD 85), range 208 to 748 μm. This species has been cited for Europe, Asia, America, Africa and Oceania. In the Iberian Peninsula, it has been recorded for Portugal ( Da Cunha 1941; Maucci & Durante Pasa 1985) and Spain ( Mihelčič 1955). Echiniscus blumi was collected at 35 sampling points (Table 3).

Figures

FIGURE 2. Morphological variability found in Echiniscus blumi. Percentages are provided for each morphotype. Arrows indicate missing appendages.