Attemsostreptus reflexus, Akkari & Enghoff, 2019

Akkari, Nesrine & Enghoff, Henrik, 2019, Revision of the genus Attemsostreptus Verhoeff, 1941 with description of a new species from Tanzania and notes on the tribe Trachystreptini Cook, 1896 (Spirostreptida, Diplopoda), European Journal of Taxonomy 575, pp. 1-12 : 3-10

Attemsostreptus reflexus sp. nov.

urn:lsid:zoobank.org:act:ACE58179-F898-43CD-A9CC-BE4121D77A8C

Figs 2–5

Diagnosis

A species of genus Attemsostreptus that differs from A. costatus in the shape of the coxal apical and lateral processes, and in the presence of coxal distomesal spines.

Etymology

The species epithet is a Latin adjective meaning ‘turned back’ and referring to the shape of the lateroapical metaplical process of the gonopod.

Material examined

Holotype

TANZANIA • 1 ♂, missing posterior part, dissected; Morogoro Reg., Morogoro Distr., Kimboza Forest Reserve ; 37°48′ E, 07°01′ S; Jan.–Mar. 1994; Frontier Tanzania leg.; NHMD 607065 .

Paratypes

TANZANIA • 1 ♂, missing posterior part; same collection data and repository as for the holotype; NHMD 607073 • 4 ♀♀, three of which broken in half and one missing posterior part; same collection data and repository as for the holotype; NHMD 607073 .

Other material examined

TANZANIA • 1 ♂, without data, mesal coxal spines (mcs) short, originating more distally than in the type specimens, mesoapical metaplical process (map) more truncate than round, distolateral spine maybe not quite so extraordinarily long, only 51 PR vs 56 PR in females from type series, body length (L) 65 mm, vertical diameter (H) 4.0 mm; NHMD 621669 • 1 ♂, HNHM diplo-1697, without data, exactly like type specimens except that (mcs) are broken, 53 PR, L 70 mm, H 4.3 mm .

Description

MEASUREMENTS. Holotype ♂: H = 4.3 mm, broken in three parts, missing posterior end. Paratypes ♂: H = 4 mm; broken, missing posterior end. Females: L = 78.5–81.2 mm; H = 4.8–5.2 mm; 56 PR.

COLOUR ( Figs 2–3 ). After several years in ethanol, orange-reddish-brown, colour more intense at margin of the posterior half of metazonites, prozonites lighter with a hint of chestnut at the lateral margins. Head dark brown in occipital area, sputtered with yellowish on frons and reddish to yellowish brown on labrum and gnathochilarium. Antenna and legs yellowish.

HEAD ( Fig. 2 ). Four supralabral setae. Antennae reaching back to body ring 6. Eyes reaching slightly beyond mesal margin of antennal socket, each with ca 10 vertical rows of ommatidia, ca 5 horizontal rows, ca 35 ommatidia. Mandible as in Tropostreptus ( Enghoff 2017) : stipes in males with a small apicoventral lobe; odontomere long, moveable; sectile edge of psectromere with ca 5 lobes; ca 12 pectinate lamellae; one wide molar furrow. Gnathochilarium: prementum simple, not depressed; mentum with deep depression basally delimited by sharp ridge, as in Pseudotibiozus ( Enghoff & Larsson 2018: fig. 3); stipites with basal row of setae adjacent to mentum, apicolaterally with field of many setae, distally with swelling harbouring one modified seta, as in Pseudotibiozus ( Enghoff & Larsson 2018: fig. 3).

COLLUM ( Fig. 2 ). With protruding antero-ventral lobes in males. Three or four lateral furrows. No antennal groove.

BODY RINGS ( Figs 2B , 3A, E ). Prozonae with non-consipicuous furrows. Metazonae with regular longitudinal striae on entire body ring circumference, areas between striae elevated as ridges, ridges projecting beyond posterior margin of ring ( Fig. 3B ). Ozopore round, visible as bright spot rimmed with grey at the middle of metazona, behind suture ( Fig. 3A ), latter thin and sometimes curving at level of ozopore. Pleurotergal lobes meeting behind posterior pair of legs on each body ring.

LEGS ( Figs 2–3 C–D). Length ca 4 mm, slightly shorter in females. Males with postfemoral and tibial pads from third pair until beyond midbody ( Fig. 2A ), pads decreasing in size posteriorly, absent from posteriormost legs. First pair of legs in male ( Fig. 3D ) similar to those of A. costatus as described by Krabbe (1982).

TELSON ( Fig. 3 E–F). Preanal ring with straight dorsal margin. Anal valves with raised median margins forming blunt lips, flanked by distinct grooves, i.e., of the “fossate” type sensu Hoffman (2011).

GONOPODS. ( Figs 4–5 ). Sternum (st) small and simple, lower than paracoxite (px).

COXA. Proplica (pp) simple, straight and broad, distomesal corner sharp, distal margin almost straight, oblique, surface in distal part with scattered bristles. Metaplica (mp) broad and stout; mesal margin straight, in basal part folded laterad as broad duplicature, subapically with large distad spine (mcs); in some specimens, (mcs) smaller and inserted more distally than in the holotype; metaplica apically gently rounded, mesoapical metaplical process (map) protruding as narrow ovoid mesal lobe, truncate in a few specimens ( Fig 5B ), meeting medially and totally lacking the meso-apical incision observed in A. costatus , laterally showing a strong constriction and protruding as lateroapical metaplical process (lap). This process (lap) very long, and strongly curved, first directed laterad, then making a U-turn and pointing distomesad to mesad in most specimens, ending in claw-like pointed apex.

TELOPODITE. With a thin and curved antetorsal process (atp) ending in a pointed apex, post-torsal part long, with several torsions and an incomplete loop, thereafter narrowing towards apex and bifurcating into a thin serrated lamella (sl) and an acuminate apical process.

Distribution

Kimboza Forest Reserve, Morogoro.

Figures

Fig. 2. Attemsostreptus reflexus sp. nov., male holotype (NHMD607065), head and anteriormost body rings. A. Ventral view. B. Lateral view. Scale bar: 1 mm.

Fig. 3. Attemsostreptus reflexus sp. nov., external structures. A. Midbody rings in lateral view, telson towards the left, female paratype. B. Limbus, male holotype (NHMD607065). C. First pair of legs, male holotype (NHMD607065). D. Midbody leg with soft pads, male holotype (NHMD607065). E. Posteriormost body rings and telson in lateral view, female paratype. F. Posteriormost body rings and telson in ventral view, female paratype. Scale bar: 1 mm.

Fig. 4. Attemsostreptus reflexus sp. nov., male holotype (NHMD607065), gonopods. A. Gonopods, anterior view.B. Right gonopod, antero-apical view. C. Telopodite.D.Tipof telopodite.For abbreviations, see Material and methods. Scale bars: A = 1 mm; B–D = 0.5 mm.

Fig. 5. Attemsostreptus reflexus, males without locality data. A. ♂, (NHMD621669). B. ♂, deviating gonopods (HNHM diplo-1697). Scale bar: 1 mm.