Riotintobolus antafoky,

Wesener, Thomas, 2020, Ecotone shifts in southern Madagascar: first barcoding data and six new species of the endemic millipede genus Riotintobolus (Spirobolida, Pachybolidae), ZooKeys 953, pp. 1-29: 1

publication ID

http://dx.doi.org/10.3897/zookeys.953.53977

publication LSID

lsid:zoobank.org:pub:BA81E879-88A2-495A-92FB-98D1F2909BA7

persistent identifier

http://treatment.plazi.org/id/9F3E2163-ACA9-4A1F-B6D0-D24CD3A692D8

taxon LSID

lsid:zoobank.org:act:9F3E2163-ACA9-4A1F-B6D0-D24CD3A692D8

treatment provided by

ZooKeys by Pensoft

scientific name

Riotintobolus antafoky
status

sp. nov.

Riotintobolus antafoky  sp. nov. Figure 9View Figure 9

Material examined.

Holotype: ♂, CASENT 9032794, MGF007, Madagascar, Province Toliara, Antafoky, 80 m, spiny thicket, 23°29'16"S, 44°4'39"E, coll. Frontier project, millipede dig (3 m x 3 m), 14.xi.2001.

Paratypes: 1 ♂, 1 ♀, CASENT 9032794, same data as holotype

Etymology.

Antafoky, after the type locality, spiny forest of Antafoky (Fig. 2View Figure 2). Noun in apposition.

Diagnosis.

R. antafoky  sp. nov. shares the flag-like membranous tip of the posterior gonopod with R. mandenensis  , R. minutus  , R. aridus  , R. anomalus  and R. makayi  sp. nov. R. antafoky  sp. nov. shares the absence of tarsal pads only with R. bovinus  sp. nov., and the relatively simple tip of the posterior gonopod only with R. anomalus  . R. antafoky  sp. nov. differs from the sympatric R. anomalus  in details of the posterior gonopod, the absence of a dorsal red stripe, the much longer antenna (protruding back to body ring 5), and the much smaller size ( R. anomalus  males 45 mm long, 4.3 mm wide, R. antafoky  sp. nov. ca. 33 mm long, 3.2 mm wide).

Description.

Measurements (holotype): 51+0 segments, ca. 33 mm long (fragmented) and 3.2 mm wide.

Coloration: segments grey, with a dark grey posterior margin, ozopore highlighted by a black spot. Head, antennae and legs dark grey.

Head: each eye with 34 ommatidia in six rows. Incisura lateralis open. Labrum with standard three irregular teeth and a single row of 10-12 stout marginal setae. Clypeus with two setiferous foveolae on each side. Antennae long, protruding back to segment 5. Terminal antennomere with four large sensory cones located together inside a membranous area. Antennomere 5 and 6 latero-apically with sensilla basiconica.

Gnathochilarium: lamellae linguales each with two standard setae located behind one another. Stipites each with three apical setae. Endochilarium not dissected.

Mandible: Stipes without projection, well rounded. Gnathal lobe not dissected.

Collum: smooth, laterally not protruding as far as ring 2.

Body rings: ozopores starting at segment 6, marked by a black spot. Located slightly before, but touching suture between meso- and metazonite. Rings with smooth, but irregular coriaceous surface, ventrally on metazona with transverse ridges.

Telson: paraprocts without lips, abundant micropunctation especially towards edges. Epiproct well-rounded, covering, but not reaching above paraproct. Hypoproct inconspicuous.

Legs: leg 1 with a large cylindrical coxa, twice as long as other podomeres. Tarsus with three pairs of ventral spines and an apical spine beyond claw. Leg 2 with an elongated coxa and a strongly swollen prefemur. Tarsus with two pairs of ventral spines and a short apical spine. Midbody legs with a rectangular coxa, as long as other podomeres. Each podomere ventrally with a single or a pair of apical setae, tarsus without a tarsal pad, a single apical and two pairs of ventral spines. Length of midbody legs ca. 0.9 times body diameter in males.

Female: not investigated.

Male sexual characters: tarsal pads absent. Coxae 3-7 without coxal processes, but coxae 6 and 7 flattened, rectangular.

Anterior gonopod sternite massive (Fig. 9AView Figure 9), elongated into a wide, well-rounded triangular lobe (Fig. 9AView Figure 9). Sternite in anterior view well-visible, without discernible apodemes, protruding almost as high as coxal processes. Coxite with sharp triangular mesal process (Fig. 9A, BView Figure 9), upper rim bending forward in anterior view (Fig. 9AView Figure 9). Telopodite with strong process arising mesally (Fig. 9BView Figure 9), process apically curved with a short triangular projection (Fig. 9AView Figure 9), tip well-rounded, protruding above lateral margin of telopodite (Fig. 9BView Figure 9).

Posterior gonopods consisting of two parts, separated by an articulation: a long coxite and a slightly shorter telopodite, efferent duct discharging apically (Fig. 9C, DView Figure 9). Process of coxite and telopodite standing in same axis (Fig. 9DView Figure 9). Pair of posterior gonopods located parallel to each other, connected by a small, sclerotised and visible sternite (Fig. 9DView Figure 9). Basal part of coxite wide, mesally with a triangular sclerite located on lower level than remaining part (Fig. 9CView Figure 9). Coxite elongated. Efferent duct running at mesal margin of coxite (Fig. 9C, DView Figure 9). Telopodite as wide as but slightly shorter than coxite, standing in same axis (Fig. 9DView Figure 9), apically with a membranous ‘flag’ (Fig. 9C, DView Figure 9). Laterally with sclerotised projection bending laterally and completely surrounded by membranous flag. (Fig. 9C, DView Figure 9). Efferent duct ending at base of process (Fig. 9C, DView Figure 9). Apex laterally with weakly developed finger-shaped process.

Remarks.

this species lives in direct sympatry with the much larger R. anomalus  .