Amastigogonus orientalis, Mesibov, Robert, 2017

Mesibov, Robert, 2017, Iulomorphid millipedes (Diplopoda, Spirostreptida, Iulomorphidae) of Tasmania, Australia, ZooKeys 652, pp. 1-36 : 15-16

Amastigogonus orientalis sp. n. Fig. 8A

Holotype.

Male, Maclaines Creek, Tas, -42.4628 147.8564 ± 100 m [label "EN 703 983" (= 55G 570300 5298300, AGD66)], 260 m a.s.l., 26 April 1991, R. Mesibov, QVM 23:54523 (in 2 pieces).

Paratypes.

2 males, details as for holotype, QVM 23:54401.

Other material.

14 males and 3 probable females from 14 unique localities; details in Suppl. material 1.

Diagnosis.

Like Amastigogonus hellyeri sp. n. in having a broad pseudoflagellum abruptly narrowed apically; distinguished by having a subquadrate extension of the posterobasal telopodite margin, with the prostatic groove opening on a very short tooth-like extension of the reduced pseudoflagellum tip, rather than on a relatively long, flexible extension.

Description.

Mature males observed with (43+3) rings, 2.6 mm midbody diameter to (67+0) rings, 4.2 mm. Cardo not deeper posteriorly. Leg 7 (only) with elongated coxa. Prefemoral pad ca 1/2 femur length. Striae on posterior metazonites reaching 3/4 ozopore height.

Coxite process on anterior gonopod (Fig. 8A) with posterodistal margin substantially extended as rounded tab and folded over laterally to ca 1/2 process width. Telopodite with posterobasal surface produced posteriorly as large rounded flange (Fig. 8A; fl) and with single row of prominent setae on posterior side of medial thickening. Pseudoflagellum ca 1/2 width of telopodite at base, expanded slightly posteriorly, tapering gradually before expanding distally in wedge shape, often curving laterally, with very short pointed extension at middle of distal margin; prostatic groove making S-bend from anterior side of pseudoflagellum into tip, terminating in pointed extension. Posterior margin of pseudoflagellum sometimes sinuous in transverse plane.

Distribution.

Eucalypt forest over ca 100 km linear extent in the Eastern Tiers of Tasmania (Fig. 7A) from ca 150 to at least 600 m elevation; the disjunction in the distribution map is likely to be a sampling artefact. Possibly parapatric with Amastigogonus elephas sp. n. near Gray; overlapping to a small extent with Amastigogonus danpicola sp. n. in the Douglas-Apsley National Park and with Amastigogonus fossuliger northwest of Triabunna; parapatric or overlapping with Amastigogonus michaelsae sp. n. in the southern Eastern Tiers.

Name.

Latin orientalis , eastern; adjective. This species is restricted to the East Coast region of Tasmania.