(173PTmac) Paratullbergia macdougalli (Bagnall, 1936)

Paratullbergia macdougalli is much less common than Paratullbergia callipygos although the records would suggest that it is probably a widespread and under-recorded species (with a possible north-easterly bias). The largest specimen seen by Steve was 0.95 mm in length. Paratullbergia macdougalli has prominent anal spines as long as a foot claw (Fig. 1), from which an empodium is absent (Fig. 2).
On the dorsal side of the second (abd2) and third (abd3) abdominal segments of Paratullbergia callipygos, the setae a2-a1-a1-a2 are in a straight line whereas in Paratullbergia macdougalli, setae a1-a1 are distinctly further forwards than the a2 setae (Figs. 3 and 4). Also in Paratullbergia callipygos, there is a pair of tubercles posterior to the crescent-shaped ridges; these tubercles are absent from Paratullbergia macdougalli (Fig. 1).

 

 

 

Fig. 1: Posterior abdomen of the holotype of Paratullbergia macdougalli collected from Corstophine near Edinburgh in April 1935 by Bagnall. There are no tubercles posterior to the crescent-shaped ridges (cr) on abd6. The anal spines are about the same length as a foot claw (cf. Fig. 2 which is at the same magnification).

Fig. 2: Foot of the third leg of the same specimen of Paratullbergia macdougalli shown in Fig. 1 (same scale as Fig. 1).

Fig. 3 (above): Dorsal side of the second (abd2) and third (abd3) abdominal segments of the same specimen of Paratullbergia macdougalli shown in Fig. 1. The area delimited by the green box is shown in Fig. 4.

Fig. 4 (above): Area delimited by the green box shown in Fig. 3. Setae a1-a1 are distinctly further forwards than the a2 setae.

 
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