Prionopetalum kraepelini ( Attems, 1896 )

Henrik Enghoff, 2016, A mountain of millipedes IV: Species of Prionopetalum Attems, 1909, from the Udzungwa Mountains, Tanzania. With notes on “ P. ” fasciatum (Attems, 1896) and a revised species key (Diplopoda, Spirostreptida, Odontopygidae), European Journal of Taxonomy 215, pp. 1-23 : 10-13

Prionopetalum kraepelini ( Attems, 1896)

Figs 5–6 , 9 R, 11I

Odontopyge kraepelini Attems, 1896: 37 .

Prionopetalum stuhlmanni Attems, 1914: 210 . New synonymy

Odontopyge pardalis – Attems 1896: 39.

Prionopetalum pardalis – Attems 1909: 52.

Prionopetalum kraepelini – Attems 1914: 210.

Not Spirostreptus pardalis Gerstäcker, 1873 .

Diagnosis

Differs from all congeners by the multi-cusped proximal telomere process ( Fig. 6 F).

Material studied (total: 9 ♂♂)

Syntypes

TANZANIA: 1♂, 1 ♀, Mhonda ( Unguru ), 6 Sep. 1888, F. Stuhlmann leg. ( ZMUH).

Other material

TANZANIA: 1 ♂, Lewa ( Usambara ), 26 Apr. 1888, F. Stuhlmann leg., holotype of Prionopetalum stuhlmanni ( ZMUH) ; 3 ♂♂, Morogoro Region, Mang’ula, at Udzungwa Ecological Monitoring Centre , 300 m, 7°50'56" S, 36°53'17" E, 28–31 Sep. 2012, T. Pape leg. ( ZMUC) ; 4 ♂♂, Morogoro Region, Udzungwa Mts, Udzungwa Ecological Monitoring Centre, Mang’ula , 07°50'44.9" S, 36°53'28.2" E, 339 m, 18–20 Jan. 2014, T. Pape & N. Scharff leg. ( ZMUC) .

Type locality

TANZANIA: Tanga Regon, Lushoto District, Usambara Mts, Lewa.

Description (male)

SIZE. Length c. 5 cm, diameter 3.2–3.6 mm, 61–65 podous rings, no apodous rings in front of telson.

COLOUR. After 1–3 years in alcohol head amber below antennae, blackish above; antennae blackish brown; collum blackish brown with light margins; body rings light brown below ozopores and immediately above, dorsally blackish brown with broad middorsal light spot; telson and legs medium brown.

ANAL VALVES. Each with a long, pointed dorsal spine and a much smaller ventral one, marginal rim raised, with 3 setae on very poorly demarcated tubercles.

LIMBUS ( Fig. 5 F). With triangular, almost equilateral, pointed lobes, external surface of lobes densely striate.

MALE LEGS. Postfemora and tibiae with large soft pads, except on first four to five and several posteriormost leg pairs.

GONOPOD COXA ( Fig. 5 A –E). Lateral margin almost straight, entirely smooth or with a tiny tubercle (lt) at c. ⅔ height. Mesal margin of proplica straight, proplical lobe (prl) in anterior view hidden behind apical expansion of metaplica. Basal part of metaplica with large, longitudinal mesad flange (mlf), separated by a deep sinus from an oblique-horizontal, two-lobed mesad flange (mof), apical part of metaplica expanded anteriad to form a process (amp) covering proplical lobe and produced disto-mesad into slender, apically bifid process (mmp).

GONOPOD TELOPODITE ( Figs 5 D–E, 6). A well-developed post-torsal spine (“femoral spine”, pts) inserted just before post-torsal narrowing. Solenomere (slm) simple, slender. Telomere with a large, proximal lobe (pxl). Proximal telomere process (tpp) elaborate, with a longitudinal 3–5-dentate flange and a slender apical process, in certain views ( Fig. 5 E) recalling the head profile of cartoon character Woody Woodpecker. Distal telomere process (tdp) only slightly broader than solenomere, apically with one margin denticulate ( Fig. 6 F).

Distribution and habitat

In addition to the newly collected material from the Udzungwa Mts, Udzungwa Ecological Monitoring Centre, Mang’ula (http://www.udzungwacentre.org/) at 300–339 m asl, O. kraepelini has been recorded from several other sites, all in Tanzania: Morogoro Region, Mhonda (Nguru) (type locality); Tanga Region, Lushoto Distr. Usambara Mts, Lewa (type locality of P. stuhlmanni ); Arusha Region, Arusha District, near Lake Babati; Dar es Salaam (the latter two records by VandenSpiegel & Pierrard 2009).

Coexisting species

At Mang’ula, P. kraepelini was collected together with another odontopygid species which will be described in a forthcoming article.

Remarks

Two of the four species of Odontopyge (re)described by Attems (1896) distinguished themselves by the possession of a peculiar, multi-cusped process on the gonopod telopodite. This process, labelled c on Attems’ figures, corresponds to the proximal telomere process (tpp) in the sense of the present paper. The two species in question were O. kraepelini , described as new, and a species which Attems identified as O. pardalis (Gerstäcker) . He later ( Attems 1914) realised that this was not the real pardalis Gerstäcker and offered the replacement name Prionopetalum stuhlmanni Attems, 1914 ( pardalis has subsequently been transferred to the genus Calyptomastix Hoffman & Howell, 2012).

The two species, kraepelini and stuhlmanni , are very similar indeed according to the descriptions and illustrations offered by Attems (1896). The only substantial apparent difference concerns the profile of the gonopod coxa. Attems (1896) provided two gonopod drawings of stuhlmanni (as pardalis ), and one of kraepelini . The three drawings are all quite different regarding the gonopod coxa profiles, but this is due to the fact that two of them, the one of kraepelini (Attems’ fig. 1) and one of those of stuhlmanni (Attems’ fig. 8), are based on gonopods macerated in KOH, whereas his fig. 7 (of stuhlmanni ) is based on unmacerated gonopods. Attems’ fig. 7 is fully compatible with the present illustrations ( Figs 5–6 ) of specimens from Mang’ula, and side-by-side comparisons of the body and gonopods of Mang’ula specimens with the holotype of stuhlmanni reveal no differences (see Fig. 2 for agreement in body size). The male syntype of kraepelini is devoid of its gonopods, and these are not retrievable elsewhere. I interpret the apparent differences between macerated gonopods of kraepelini ( Attems 1896: fig. 1) and stuhlmanni ( Attems 1896: fig. 8) as being artificial and possibly due to different durations of the KOH maceration, and I therefore synonymize the two names.

Knob-like intercalary cuticular micro-scutes were observed in this species ( Fig. 5 G), cf. Enghoff (2014).

Under the name Prionopetalum stuhlmanni this species is a popular pet millipede; see, e.g., Sigling (2010) and http://www.diplopoda.de/index.php (accessed 29 February 2016).

Figures

Fig. 2. Body size (body diameter / number of podous rings) of ♂♂ of Prionopetalum spp. Based on original measurements and data from the literature (see Table 1). For “ other spp. ” the entries are median values of the intervals in Table 1. The report of “ 93 (1) Rumpfringen ” (corresponding to 92 podous rings) for P. tanganjikum by Verhoeff (1941) has been omitted, as has Chamberlin’s (1927) “ nearly fourtythree ” segments for P. clarum; both are regarded as quite unlikely and are probably erroneous.

Fig. 5. Prionopetalum kraepelini (Attems, 1896), specimen from Mang’ula, 339 m asl. A – C. Right gonopod coxa. A. Anterior view. B. Anterior-mesal view. C. Mesal view. D – E. Left gonopod. D. Posterior view. E. Anterior-mesal view. F. Midbody-dorsal limbus. G. Row of intercalary microscutes with knobs, from midbody metazona. Abbreviations: amp = anterior metaplical process; lt = lateral coxal tubercle; mlf = metaplical longitudinal flange; mmp = distomesal metaplical process; mof = metaplical oblique / horizontal flange; prl = proplical lobe. Scale bars: A – E = 0.1 mm; F – G = 0.001 mm.

Fig. 6. Prionopetalum kraepelini (Attems, 1896), specimen from Mang’ula, 339 m asl. Gonopod telopodite. A, C – D, F. Right gonopod telopodite. A. Posterior view. C. Apical (ventral) view. D. Anterior view. F. Telomere distal process. B. Tip of left solenomere. E. Left gonopod, (posterior-) mesal view. Abbreviations: pts = post-torsal spine; pxl = proximal lobe of telomere; slm = solenomere; tdp = telomeral distal process; tpp = telomeral proximal process. Scale bars: A, C – D, E = 0.1 mm; B, F = 0.2 mm.

Fig. 9. Prionopetalum spp., outlines of distal part of gonopod coxa. The species appear in the sequence in which they key out in the identification key. A. P. megalacanthum (after a specimen in NHMW). B. P. frundsbergi (based on Kraus 1960). C. P. bifidum (based on VandenSpiegel & Pierrard 2009). D. P. tricuspis (based on Brolemann 1920). E. P. aculeatum (based on Kraus 1960). F. P. ndelei (based on VandenSpiegel & Pierrard 2009). G. P. serratum (based on Kraus 1960). H. P. dentigerum (based on Kraus 1960). I. P. tanganjikum (based on Kraus 1960). J. P. xerophilum (based on Kraus 1960). K. P. clarum (based on Kraus 1960). L. P. pulchellum (based on Kraus 1960). M. P. etiennei (based on Demange 1982). N. P. lindi (based on VandenSpiegel & Pierrard 2009). O. P. coronatum (based on Kraus 1958). P. P. exaratum (based on Kraus 1960). Q. P. cornutum (based on Kraus 1960). R. P. kraepelini (orig.). S. P. glomeratum (based on Attems 1935). T. P. urbicolum (based on Kraus 1960). U. P. suave (based on Kraus 1960). V. P. fryeri (based on Kraus 1960). W. P. asperginis sp. nov. (orig). Not to scale.