Pogonosternum nigrovirgatum ( Carl, 1902 )

Decker, Peter, Mesibov, Robert, Voigtländer, Karin & Xylander, Willi E. R., 2017, Revision of the Australian millipede genus Pogonosternum Jeekel, 1965, with descriptions of two new species (Diplopoda, Polydesmida, Paradoxosomatidae), European Journal of Taxonomy 259, pp. 1-34 : 11-15

Pogonosternum nigrovirgatum ( Carl, 1902)

Figs 1 , 2B–E, 3, 5A–B, D–E, 6B, 7–11, 26A

Strongylosoma nigrovirgatum Carl 1902: 567 , figs 1, 2.

Pogonosternum nigrovirgatum infuscum Jeekel 1982a: 203 , 207; fig. 3; syn. nov.

Pogonosternum coniferum Jeekel 1965: 13 , figs 2, 7; syn. nov.

Strongylosoma nigrovirgatum – Brölemann 1916: 539 (mention). — Chamberlin 1920: 120 (record). — Shelley et al. 2000: 97 (record).

Akamptogonus nigrovirgatus – Attems 1914: 222 (key, new combination), 223 (record). — Attems 1937: 253–254 (key, redescription), fig. 316. — Jeekel 1968: 18 (record). — Rowe & Sierwald 2006: 533 (mention).

Pogonosternum nigrovirgatum – Jeekel 1965: 9 (redescription, new combination), figs 1, 3–6. — Jeekel 1968: 30 (mention). — Jeekel 1981: 51 (record). — Jeekel 1982a: 202–207 (mention, key). — Decker 2016a: 16–27 (record, mention).

Pogonosternum nigrovirgatum nigrovirgatum – Mesibov 2004: 42 (record). — Nguyen & Sierwald 2013: 1158 (record).

Pogonosternum nigrovirgatum infuscum – Mesibov 2004: 42 (record). — Nguyen & Sierwald 2013: 1158 (record).

Pogonosternum coniferum – Jeekel 1968: 20–30 (record, mention). — Jeekel 1981: 51 (record). — Jeekel 1982a: 202–208 (mention, key). — Mesibov 2004: 42 (record). — Nguyen & Sierwald 2013: 1158 (record). — Decker 2016a: 16–25 (record, mention).

Diagnosis

Differs from the other Pogonosternum species in having two lighter paramedian stripes and a median darker stripe; from P. jeekeli Decker , sp. nov., primarily by lateral process (lp) often shorter, not reaching or projecting most distad position of prolongation of femorite (prof), male tarsal and tibial brushes present to legpair 7, sometimes present to legpair 9, but then prof distinctly elongated and broadly curved.

Material studied

Lectotype (here designated) AUSTRALIA: 1 ♂ Strongylosoma nigrovirgatum , Victoria, Melbourne, leg. Konsul Martin ( GMNH) . Paralectotype (here designated)

AUSTRALIA: 1 ♀ Strongylosoma nigrovirgatum , same data as lectotype ( GMNH).

Other material examined

See Supplement 1 (total: 82 localities, 214 ♂♂, 118 ♀♀, 11 juv.)

Description

MEASUREMENTS. Length ca 1.7–2.4 cm; midbody width ca 1.7–2.2 mm.

COLOURATION. Colour in fresh material ( Figs 8 , 26A ): margin of lateral edges of collum often slightly to distinctly lighter ( Fig. 8B ). Dorsum with 2 paramedian light yellowish brown stripes and darker median brown stripe. On prozonites the trapezoidal paramedian light band slightly broader anteriorly, and on metazonites slightly broader posteriorly, broadest at 1/3 of length ( Figs 8D , 26A ). Median darker stripe narrow to rhombic, broadest 3/4 of length on metazonites and prozonites. Flanks often distinctly lighter. Area around ozopores slightly to distinctly lighter, cloudy pale ( Fig. 8C ).

STERNITES. Sometimes with slightly developed sternal cones, especially in anterior and midbody rings.

LEGS. Male tarsal and tibial brushes present from legpair 1 to 7 or 9, rarely to 8. Male coxa of legpair 6 and 7 slightly swollen to cone-like. Female coxa of legpair 2 rarely with slightly enlarged rounded

GONOPODS. Considerable variability present ( Figs 1 , 9–10 ). Femorite (F) moderately long and wide. Prolongation of femorite (prof) long to very long, S-shaped. Apical part of prof ranging from short, directed straight distad ( Fig. 9 A–D), to long, curving posterolaterally, nearly reaching tip of lateral process (lp) ( Fig. 9 E–H). Femoral process 1 (fp1) laminate, short, more or less broadly subtriangular with pointed tip, often slightly curved posteriad, not reaching lp and solenomere (S). Femoral process 2 (fp2) small, knob-like to subtriangular. Lateral process (lp) on lateral side of prof, short to long, slender, directed distolaterally, sometimes projecting distad of solenomere.

broadly extended, not lobiform and spiracular filter not or slightly protruding. Posterior spiracle ovoid with low rim, spiracular filter not protruding ( Fig. 11 ).

Distribution

From Central Gippsland and central Victoria to the Otway Ranges and Ballarat area; also present in northwestern Tasmania and on King Island ( Fig. 7 ). It has recently been found in the city of Launceston in north central Tasmania, and is apparently introduced there (with short prof).

Remarks

Carl (1902) described Strongylosoma nigrovirgatum based on one male and one female in the Muséum d’histoire naturelle de la Ville de Genève. The male right gonopod is missing. We designate the male as lectotype and female as paralectotype.

The subspecies P. nigrovirgatum infuscum , described from Central Gippsland, only differs by a broader fp1 from the nominate species. In the material studied here, including material from the type locality of P. nigrovirgatum , the width of the fp1 differed within some populations from slender to broadly infuscum -like. Pogonosternum n. infuscum is treated here as a synonym of P. nigrovirgatum .

Specimens fitting the description of P. coniferum by Jeekel (1965) are restricted to the coastal area around Port Philip Bay. These have a very long and curved prof, a moderate to long lp, and male tarsal and tibial brushes present from legpair 1 to 9 ( Fig. 9 E–H), while in P. nigrovirgatum sensu stricto, distributed from northern central Victoria to Gippsland, prof and lp are short and tarsal and tibial brushes are present to legpair 7 ( Fig. 9 A–D). However, the Tasmanian, Otway Ranges and western central Victorian populations contain long coniferum -like ( Fig. 9 E–H) to intermediate states of prof ( Fig. 10 ), sometimes both forms present within one population, with male brushes ranging to legpair 7, except in Brisbane Ranges National Park to legpair 9. Pogonosternum coniferum is here made a synonym of P. nigrovirgatum due to the existence of these intermediate forms and the fact that P. coniferum clusters with P. nigrovirgatum in a phylogenetic analysis based on mitochondrial COI and 16S rDNA sequences ( Decker 2016a).

The mention of Pogonosternum in northwestern Tasmania by Jeekel (1982a: 202) probably refers to P. nigrovirgatum , although Jeekel does not state what material he examined.

Figures

Fig. 1. Right gonopod of Pogonosternum nigrovirgatum (Carl, 1902), mesal view (NMV K-12158). Scale bar: 0.5 mm.

Fig. 8. Pogonosternum nigrovirgatum (Carl, 1902), ♂, from Kennett River, Grey River Road (NMV K-13114). A–B. Anterior rings. A. Left lateral view. B. Dorsal view. C–D. Rings 10 and 11. C. Left lateral view. D. Dorsal view. E–F. Posterior rings. E. Left lateral view. F. Dorsal view. Scale bars: 1 mm.

Fig. 26. Habitus and live colouration. A. Pogonosternum nigrovirgatum (Carl, 1902), ♂ from Adams Creek Nature Conservation Reserve (SMNG VNR016989). B. P. adrianae Jeeker, 1982, ♂ from Grand Ridge Road (NMV K-13349). C. P. laetificum Jeeker, 1982, ♂ from Toolangi State Forest, Two Hills Road. D. P. jeekeli Decker, sp. nov., ♂ from Warby-Ovens National Park, Taminick Gap Road. E. P. montanum Decker, sp. nov., ♂ (left, NMV K-12183) and ♀ (right, NMV K-13351) from Linden Roth Drive. Scale bars = 5 mm.

Fig. 9. Pogonosternum nigrovirgatum (Carl, 1902), ♂, right gonopod. A–D. AMS KS96017 Ferntree Gully. E–H. NMV K-10248 from Sandringham and Brighton. A, E. Posterior view. B, F. Lateral view. C, G. Anterior view. D, H. Mesal view. Scale bars: 0.5 mm.

Fig. 10. Pogonosternum nigrovirgatum (Carl, 1902), male, right gonopod (QM 23:40346). A. Posterior view. B. Lateral view. Scale bars: 0.5 mm.

Fig. 11. Pogonosternum nigrovirgatum (Carl, 1902), male, spiracles, midbody ring, left lateral view (NMV K-12158). Scale bar: 0.1 mm.

Fig. 7. Map of southeastern Australia and Tasmania, showing the known distribution of Pogonosternum spp.: red circles = P. nigrovirgatum (Carl, 1902); green stars = P. laetificum Jeeker, 1982; yellow squares = P. adrianae Jeeker, 1982; blue triangles = P. montanum Decker, sp. nov.; orange diamonds = P. jeekeli Decker, sp. nov. Abbreviation: ACT = Australian Capital Territory.