Chaleponcus malleolus, 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 : 25-27

Chaleponcus malleolus sp. nov.

urn:lsid:zoobank.org:act:85393BDE-7999-4CD5-BFA2-2B21A022E2A8

Figs 4 , 9 , 14

Diagnosis

Small (smallest species in the C. dabagaensis group). Differs from all other group members, except C. teres sp. nov., by the absence of a dorsal spine on each anal valve. Further differs from all other group members by the profile of the gonopod coxal tip ( Fig. 9 ), especially the strongly curved, hooklike lateral process.

Etymology

The name is a Latin noun, here in apposition, meaning ‘little hammer’, and refers to the gonopod coxa profile.

Material studied (total: 14 ♂♂)

Holotype

TANZANIA: ♂, Iringa Region, Iringa District, Udzungwa Mts, New Dabaga / Ulangambi FR, 08°00’ 26.6” S, 35°56’ 06.1” E, montane forest, 1910 m asl, plot Kinyonga, casual, 24 Oct. 2000, Frontier Tanzania ( ZMUC).

Paratypes

All from TANZANIA, Iringa Region, Iringa District, Udzungwa Mts, New Dabaga/Ulangambi FR, all collected by Frontier Tanzania, all in ZMUC: 1 ♂, 08°00’ 26.6” S, 35°56’ 06.1” E, montane forest, 1910 m asl, plot Kinyonga, casual, 24 Oct. 2000; 9 ♂♂, 08°00’ 26.6” S, 35°56’ 06.1” E, scrub/thicket/bush, 1904–1915 m asl, plot Kinyonga, 18–20 Oct. 2000; 3 ♂♂, 08°03’ 39.9” S, 35°54’ 41.9”’ E, montane, 1945 m asl, plot 24, 29 Oct. 2000.

Type locality

TANZANIA: Iringa Region, Iringa District, Udzungwa Mts, New Dabaga/Ulangambi FR, 08°00’ 26.6” S, 35°56’ 06.1” E, montane forest, 1910 m asl.

Description (male)

DIAMETER. 1.7–1.8 mm, 38–39 podous rings.

COLOUR. After 13 years in alcohol pale yellowish, traces of dark dorsolateral bands and a pale middorsal band.

ANAL VALVES. Neither dorsal nor ventral spines; marginal rim not raised, setiferous tubercles small, not on ‘ravelins’.

LIMBUS ( Fig. 4I ). With very low, smooth lobes, ca. 0.2 times as long as broad.

TARSAL SETATION. Normal.

GONOPOD COXA ( Figs 9 , 14 ). Almost 4 × as long as wide; lateral margin very slightly convex up to level of proplical lobe, then curving laterad and then basad, forming cucullar hook together with otherwise almost straight apical margin; cucullus (cu) short, with big lateral, basad, blunt-tipped strongly curved hook. Metaplical flange ending in blunt, apicad process (mfp); metaplical mesal margin straight, but with triangular process (mp) just below level of arculus. Metaplical shelf mainly projecting mesad, continuing without transition in metaplical shelf-spine (mss). mss medium long, curving almost exclusively in horizontal plane, first anteriad, then mesad.

GONOPOD TELOPODITE ( Fig. 14 ). Solenomere without a spine or other secondary branches. Telomere

simple, distally with 2, closely adjoining branches:

• an oblong anterior lamella (al),

• a posterior lamella forming a direct distal continuation of main stem (st) and distally with three short lobes: apical (pl1) and intermediate (pl2) lobe, with irregularly jagged edges, basal lobe (pl3) smooth-edged, semicircular.

Distribution and habitat

Only known from New Dabaga/Ulangambi FR. Altitudinal range: 1904-1945 m asl. Habitat: montane forest, scrub/thicket/bush.

Coexisting species

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

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. 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. 14. Chaleponcus malleolus sp. nov., right gonopod. A. Anterior view. B. Mesal view, focus on coxa. C. Posterior view. D. Anterior-mesal view. E. Mesal view, focus on telopodite. F. Telopodite, ventral-posterior view. al = anterior lamella of telomere, cu = cucullus, mfp = metaplical flange process, mp = mesal metaplical process, mss; metaplical shelf-spine, pl1, pl2, pl3 = lobes of posterior lamella of telomere, st = main stem of telomere. Scales 0.1 mm.