Emphysemastix Hoffman, 1966

Olsen, Sissel Anna, Rosenmejer, Trine & Enghoff, Henrik, 2020, A mountain of millipedes IX: Species of the family Gomphodesmidae from the Udzungwa Mountains, Tanzania (Diplopoda, Polydesmida), European Journal of Taxonomy 675, pp. 1-35 : 18-20

Genus Emphysemastix Hoffman, 1966

Diagnosis (after Hoffman 2005, modified)

Small to moderate-sized (length 32–65mm)gomphodesmids,pore formula:5,7, 9–19. Four apical sensory cones on antennae, clear, transverse fossa present on 5 th and 6 th antennomere. Collum asymmetrically narrowed laterally, with a shallow emargination in the posterior edge. Paranota placed high on the sides, moderate to large in size, dorsum only slightly convex. Sterna broad, with two transverse carinae on posterior end of body ring 8, four transverse carinae on rings 9–19 (except E. congdoni Hoffman, 2005 and E. dracarys sp. nov.). Coxae and prefemora with long hairs originating in clear basal tubercles on at least posterior legs. Sides of metazona smooth. Torus ( Fig. 4B ) present as small, distinct, cone-shaped projections. Subonychial pads on male legs 1–6. Sternal process of segment 6 long and slender, with median apiculus ( Fig. 5A ). Paxillus ( Fig. 4A ) present on sternum of body ring 15 (except in E. congdoni ). Gonopod aperture asymmetrically oval, extended back between the 8 th pair of legs, quite large, posterior edge elevated behind the gonocoxae, but not in front of coxae of the 8 th pair of legs. Rim of aperture is thickened, variously emarginate medially. Gonocoxa slanting and shortened as usual, not produced over base of cannula. Prefemoral region without basal fossa on the median side, but deeply impressed on lateral side (where surface is membranous), making prefemur seem almost like carina. Telepodite endonodal. Process M present, varies in both size and shape (exception: E. dracarys sp. nov.). Process L can be quite small, but is larger in some species. Postnodal telopodite curved dorsomesad, with a subglobose, hollow enlargement along the outer curvature. Apex of telopodite with a subterminal process of variable shape and size (e.g., Fig. 15 ).

Included species

Emphysemastix trepidans ( Attems, 1931) (type species)

Emphysemastix congdoni Hoffman, 2005

Emphysemastix dracarys Olsen & Enghoff sp. nov.

Emphysemastix flavosignatus ( Carl, 1909)

Emphysemastix frampt Olsen & Enghoff sp. nov.

Emphysemastix image Hoffman, 2005

Emphysemastix magnifrater Hoffman, 2005

Distribution

Tanzania. None of the previously described species are known from the Udzungwa Mts.

Key to species of Emphysemastix (modified after Hoffman 2005)

1. Basal setose side of gonopod prefemur unmodified, as seen in mesal aspect not extended ventrad as a distinct subtriangular lobe ( Hoffman 2005: fig. 201) ..................................................................... 2

– Basal setose side of prefemur projected ventrad as a more ( Hoffman 2005: fig. 204) or less ( Figs 14 , 17 ) distinct subtriangular lobe ........................................................................................................... 3

2. Postnodal telopodite very short, scarcely longer than distal lobe of nodus; nodal process M long and slender, projecting dorsally well beyond telopodite ( Hoffman 2005: fig. 201); sterna with sharp transverse carinae, body ring 15 with sternal paxillus............................ E. trepidans ( Attems, 1931)

– Postnodal telopodite 3–4 × as long as distal lobe of nodus; nodal process M small and short, not extending beyond edge of telopodite ( Hoffman 2005: fig. 202); sterna without transverse carinae, 15 th body ring without paxillus ............................................................... E. congdoni Hoffman, 2005

3. Nodal process M absent ( Fig. 14 )............................................ E. dracarys Olsen & Enghoff sp. nov.

– Nodal process M present ................................................................................................................... 4

4. Nodal process M broadly laminate, apical edge truncate and serrate ( Hoffman 2005: fig. 205); distal nodal lobe elongate and subrectangular in mesal aspect; body width 14 mm ................................................................................................ E. magnifrater Hoffman, 2005

– Nodal process M slender, subterete, gradually acuminate; distal nodal lobe shorter and subovoid; body narrower.................................................................................................................................... 5

5. Nodal process L long, visible in mesal aspect; postnodal telopodite of moderate length, not extending proximad beyond base of cannula ..................................................................................................... 6

– Nodal process L very small, not visible in mesal aspect; postnodal telopodite very long, extending proximad far beyond base of cannula ( Hoffman 2005: fig. 207)................. E. image Hoffman, 2005

6. Body width 9.0– 9.3 mm. Paxillus triangular, pointed. Gonopodal nodus subrectangular, processes M and L relatively short, straight ( Hoffman 2005: fig. 206)..................... E. flavosignatus ( Carl, 1909)

– Body width 13.1 mm. Paxillus rounded. Gonopodal nodus with slightly diverging sides, processes M and L longer, more curved ( Fig. 17 )....................................... E. frampt Olsen & Enghoff sp. nov.

Figures

Fig. 4. Particular gomphodesmid structural elements. A. Paxillus – a mid-ventral, most often triangular process on body ring 15 in most gomphodesmid males, from Hoffman (2005), modified. B. Torus – a low convexity of variable size and shape, found on the ventral surface of the poriferous paranota in males of many gomphodesmid species. Not drawn to scale.

Fig. 5. Sternal process on body ring 6. A. Emphysemastix spp. B. Agrophogonus spp. except A. hamulifer Olsen & Enghoff sp. nov. C. Agrophogonus hamulifer Olsen & Enghoff sp. nov. D. Pogoropsis prolixopes Rosenmejer & Enghoff gen. et sp. nov. E. Pogoro siren Rosenmejer & Enghoff sp. nov. F. Pogoro scharffi Hoffman, 2005. G. Pogoro alopias Rosenmejer & Enghoff sp. nov. Not drawn to scale.

Fig. 15. Emphysemastix spp., gonopod tip. A. E. dracarys Olsen & Enghoff sp. nov., holotype, ♂ (NHMD 621675). B. E. frampt Olsen & Enghoff sp. nov., holotype, ♂ (NHMD 621677). Abbreviations: so = solenomere; sp = subterminal process. Scale bars: 0.25 mm.

Fig. 14. Emphysemastic dracarys Olsen & Enghoff sp. nov., holotype, ♂, left gonopod (NHMD 621675). A–B. Mesal view. C–D. Lateral view. E–F. Dorsal view. Abbreviations: L = Process L; rl = rounded lobe; sg = subglobose enlargement; sp = subterminal process. Scale bars: 0.5 mm.

Fig. 17. Emphysemastix frampt Olsen & Enghoff sp. nov., holotype, ♂ (NHMD 621677), left gonopod. A–B. Mesal view. C–D. Lateral view. E–F. Dorsal view. Abbreviations: L = Process L; M = Process M; rl = rounded lobe; sg = subglobose enlargement. Scale bars: 1 mm.