Chaleponcus teres, Enghoff, 2014

Enghoff, Henrik, 2014, A mountain of millipedes I: An endemic species-group of the genus Chaleponcus Attems, 1914, from the Udzungwa Mountains, Tanzania (Diplopoda, Spirostreptida, Odontopygidae), European Journal of Taxonomy 100, pp. 1-75 : 51-53

Chaleponcus teres sp. nov.

urn:lsid:zoobank.org:act:F4EB8A22-2F19-438F-8C65-DB6091867337

Figs 4 , 6 , 9 , 25

Diagnosis

Medium-sized. Differs from all other group members, except C. malleolus sp. nov., by the absence of a dorsal spine on each anal valve. Further characterized by the subquadratic outline of the cucullus and the structure of the telomere, especially the presence of a slender, sinuous, spine-like branch. Gonopod coxa ( Fig. 9 ) without a lateral process; metaplical shelf-spine long.

Etymology

The name is a Latin adjective meaning “smooth” and refers to the spineless anal valves.

Material studied (total: 29 ♂♂)

Holotype

TANZANIA: ♂, Iringa Region, Iringa District, Udzungwa Mts, New Dabaga / Ulangambi FR, 08°04’ 05.7” S, 35°54’ 18.8” E, montane, 1930–1950 m asl, plot 1, casual, 16–19 Oct. 2000, Frontier Tanzania leg. ( ZMUC).

Paratypes

All from TANZANIA, Iringa Region, Iringa District, Udzungwa Mts, New Dabaga/Ulangambi FR, all collected by Frontier Tanzania, all in ZMUC: 27 ♂♂, 08°04’ 05.7” S, 35°54’ 18.8” E, montane, 1930– 1950 m asl, plot 1, casual, 16–19 Oct. 2000; 1 ♂, 08°04’ 05.7” S, 35°54’ 13.8” E, montane, 1940 m asl, plot 1, sample 3 of 3, 19 Oct. 2000.

Type locality

TANZANIA: Iringa Region, Iringa District, Udzungwa Mts, New Dabaga/Ulangambi FR, 08°04’ 05.7” S, 35°54’ 18.8” E, montane, 1930–1950 m asl.

Description (male)

DIAMETER. 1.9–2.2 mm, 45–47 podous rings.

COLOUR. After 12 years in alcohol yellowish, with dark spots at ozopores and paramedian dark dorsal bands flanking a mid-dorsal light stripe; paramedian dark colouration sometimes extending down flanks on metazonites, giving the body a ringed appearance; body rings 6 and 7 darker than the others.

ANAL VALVES ( Fig. 6D ). Entirely without dorsal and ventral spines; marginal rim not raised, setae not on tubercles.

LIMBUS ( Fig. 4H ). With low, broad, rounded lobes, separated by parabolic sinuses; each lobe ca. 4 times broader than long, margin densely and finely serrate, lobes indistinctly striate on external surface.

TARSAL SETATION. Normal.

GONOPOD COXA ( Figs 9 , 25 ). About 3½ × as long as wide. Lateral margin straight in basal 2/3, then shallowly concave, angle between lateral and apical margins 90°, sharp; cucullus (cu) hence subquadratic. Metaplical flange (mf) smoothly rounded, no angle, no process; metaplical mesal margin straight up to level of arculus. Metaplical shelf (ms) forming subrectangular process just distal to arculus, followed by very deep incision (in) separating cucullus from basal part of metaplica; ms proximally stout, continuing

in metaplical shelf-spine (mss) with no clear demarcation. mss medium long, originating from anteriordistal surface of ms, first projecting distad, then curving mesad, and then slightly basad.

GONOPOD TELOPODITE ( Fig. 25 ). Solenomere with a small, inconspicuous, irregular proximal spine (ps).

Telomere without a separate proximal lobe but posterior margin of proximal part of main stem (st’) lying

closely against base of solenomere (slm). Telomere distally with three branches:

• A large, roughly rectangular basal lamella (bal) carrying a secondary lamella (bal’) on its lateral side,

• A distal spine-like branch, slender and sinuous (spl),

• An irregular apical lamella dividing in two branches, proximal branch (al1) with smooth margins, the distal branch (al2) with irregularly serrated margin. al1 and bal in situ curving around opposite coxa ( Fig. 25A ).

Distribution and habitat

Known only from Udzungwa Mts, New Dabaga/Ulangambi FR. Altitudinal range: 1930–1950 m asl. Habitat: montane forest.

Coexisting species

C. termini sp. nov. and C. vilici sp. nov. were found in the same samples as C. teres sp. nov. In addition, C. dabagaensis , C. gracilior sp. nov., C. krai sp. nov., C. malleolus sp. nov., C. mwabvui sp. nov., C. nectarinia sp. nov., C. netus sp. nov. and C. vandenspiegeli sp. nov. occur in New Dabaga/ Ulangambi FR.

Notes

The gonopods somewhat resemble those of C. hamerae sp. nov.

Figures

Fig. 4. Limbus types in Chaleponcus species, SEM micrographs, external view, except I: internal view. — A. Lobes pointed, more than twice as long as broad (C. scopus sp. nov.). B. Lobes pointed, slightly less than twice as long as broad (C. howelli sp. nov.). C. Lobes pointed, almost equilateral triangles (C. netus sp. nov.), D. Lobes rounded, slightly longer than broad (C. dabagaensis Kraus, 1958). E. Lobes broadly rounded, slightly shorter than broad (C. hamerae sp. nov.). F. Lobes spatulate (C. gracilior sp. nov.). G. Lobes rounded, broader than long, spinose, ridged (C. krai sp. nov.). H. Lobes ca. 3 times as broad as high, rounded, spinose (C. teres sp. nov.). I. Lobes rounded, much broader than high, smooth (C. malleolus sp. nov.). J. No lobes (C. circumvallatus sp. nov.). Scales: 0.01 mm (A– F, J), 0.001 mm (G–I).

Fig. 6. Telson types in Chaleponcus species. — A. Dorsal and ventral anal valve spines well developed (C. nectarinia sp.nov.).B.Spinesverylong(C.circumvallatussp.nov.).C.Dorsal spinewell developed, ventral spinebarelyindicated(C.mwabvuisp.nov.).D.Nospines(C.teressp.nov.).E.Setiferoustuberclesonravelins (C. nectarinia sp. nov.). F. With setiferous tubercles, not on ravelins (C. mwabvui sp. nov.). Scales 0.1 mm.

Fig. 9. Chaleponcus spp., outline of coxite of left gonopod, posterior view. (The ’transverse’ plane of the gonopod is usually slightly at angles with the exact transverse plane of the millipede, so it may be necessary to tilt the gonopod slightly in order to obtain the view shown on the drawings.) The stippled lines indicate the place where the telopodital basomere emerges from the coxal cavity. Not to scale.

Fig. 25. Chaleponcus teres sp. nov., gonopods. A. Gonopods in situ in seventh body ring, anterior view. B. Left gonopod, mesal view. C. Right gonopod, base of solenomere and telomere, ventral view. D. Right gonopod, posterior view. E. Left gonopod, anterior(-lateral-ventral) view. F. Right telopodite, mesalanterior-ventral view. G. Right telopodite, mesal-anterior view. al1, al2 = branches of apical telomeral lamella, bal, bal’ = basal lamella of telomere, cu = cucullus, in = metaplical incision, mf = metaplical flange, ms = metaplical shelf, mss = metaplical shelf-spine, ps = proximal spine of solenomere, slm = solenomere, spl = spine-like lamella of telomere, st, st’ = main stem of telomere. Scales 0.1 mm.