Echiniscus curiosus Claxton, 1996

Pilato, Giovanni, Binda, Maria Grazia & Lisi, Oscar, 2005, Remarks on some Echiniscidae (Heterotardigrada) from New Zealand with the description of two new species, Zootaxa 1027 (1), pp. 27-45 : 27-45

Echiniscus curiosus Claxton, 1996 ( Fig. 5 )

Material examined: North Island , Featherston summit: 2 specimens from a sample of Thuidiopsis furfurosa (moss) on rock in stream .

Horning et al. (1978) identified as Echiniscus quadrispinosus Richters, 1902 brachyspinosus Bartos, 1930 some specimens with “the typical E. quadrispinosus pore

pattern in the dorsal plates” and “with lateral spines B, C, D and E and dorsal spines Cd and

Dd ”.

In two of the specimens so named by Horning et al. (1978) we noted that there is a plate sculpture different from that of E. quadrispinosus and they lack spines B ( Fig. 5 ).

The plate sculpture ( Fig. 5 ) consists of dots surrounded by a crown of pores. The pattern of the surrounding pores is random on the head and scapular plates, on the median plates and on the anterior portions of the paired plates II and III; while on the posterior portion of the above mentioned paired plates II and III and on the terminal plate, the pores tend to be arranged in a well defined circular pattern. The paired plates II and III have a transversal smooth band; the anterior portions of these plates also have an oblique smooth band ( Fig. 5 B ).

The two specimens more closely resemble Echiniscus curiosus Claxton, 1996 of which we examined five paratypes ( Fig. 6 ) kindly sent to us by Sandra Claxton.

Claxton (1996) described Echiniscus curiosus from Australia and noted three spine combinations in adults: A, C, D; A, C, D, E, Dd; and A, C, D, E, Cd, Dd; juveniles also showed two other spine combinations: A, E; and A, E, Dd. Some specimens were also provided with appendages Bd.

As mentioned earlier, examiation of two paratypes of E. zetotrymus raised doubts about their identity: either they do not belong to E. zetotrymus or E. zetotrymus is more variable than described by Horning et al. (1978). Those paratypes have the same plate sculpture as E. curiosus , lateral appendages A, C, D, E and dorsal appendages Cd.

Considering that the appendage Dd may be absent in E. curiosus ( Claxton 1996, p. 21) , the only difference between E. curiosus and the examined paratypes of E. zetotrymus is the different length of the appendage E.

In conclusion, probably the examined paratypes of E. zetotrymus can be ascribed to E. curiosus ; but taking into consideration the variability of the lateral and dorsal appendages of E. zetotrymus , an examination of the holotype of this species is necessary to establish whether E. curiosus Claxton, 1996 is a synonym of E. zetotrymus Horning et al., 1978 .

Echiniscus curiosus is new for New Zealand; the presence of Echiniscus quadrispinosus brachyspinosus in New Zealand needs to be confirmed.

Figures

FIGURE 5. Echiniscus curiosus: A, B, details of the plate sculpture. Scale bar = 10 m.

FIGURE 6. Echiniscus curiosus (paratype). Scale bar = 30 m.