Iulidesmus sabaneta, Romero-Rincon & Golovatch, 2024

Romero-Rincon, Juan & Golovatch, Sergei I., 2024, The millipede genus Iulidesmus Silvestri, 1895 in Colombia (Polydesmida, Paradoxosomatidae, Catharosomatini), Zootaxa 5415 (1), pp. 56-76 : 66-68

Iulidesmus sabaneta new species

Figs 8 , 9 , 14

urn:lsid:zoobank.org:act:12A43986-6F9C-417B-A1BA-D0F948E74E69

Diagnosis. The new species seems to be particularly similar to both I. minerus n. sp. and I. florezi n. sp., but it differs from congeners by the gonopodal conformation in addition to the observations already mentioned above: solenophore (sph) with evident overlapping elements in the apical region; medial distal element much longer and larger than lateral distal element, and the evident encasement at the base of the sph that surrounds the solenomere (sl).

Name. After the type locality: Sabaneta , Antioquia; a noun in apposition .

Material examined.

Holotype. COLOMBIA ● ♂; Antioquia, Sabaneta (6°9′3′′N, 75°36′54′′W); 28 October 2022; K. López leg.; (MHN-UPN-MD-123).

Description. Length of holotype, 24 mm, width of midbody metazona, 2.4 mm. Coloration in alcohol reddish black 24. Antennae reddish black 24 with lighter distal borders, tip of antenna entirely pallid and legs: prefemur, femur and postfemur 56 deep brown 56. vs tibia and tarsus pale yellow 89.

Body strongylosomoid, not moniliform, with poorly developed paraterga ( Fig. 8 ). Postcollar constriction evident; in width, head = ring 2 = 3 <4 <collum <5 – 16; on rings 17 – 20, trunk gradualky tapering towards telson. Antennae long, claviform, in situ reaching the middle of ring 5 ( Fig. 8 ); in length, antennomeres 3>5>2=4>6>1=7.

Paraterga set low (at about half midbody height), considerably larger on pore-bearing rings than on poreless ones, never projecting caudally past rear tergal margin, flattened and decreasing in size only from ring 17 towards telson. Transverse mid-dorsal sulci present on rings 5–18, very faint, thin lines not reaching the bases of paraterga. Ozopores lateral, invisible from above, located inside round to ovoid grooves, lying on paraterga at ca 1/3 metazonital length off caudal edge. Tegument generally smooth, 2+2 long setae (each ca 0.23 mm long) or their insertion points anteriorly in one transverse row on each postcollar metatergum.

Sterna with evident transverse cross-impressions, slightly setose, traceable sternal cones (male) very small and moderately setose between the coxae 4–7 except for the cones between coxae 4, a little larger than the rest and more axially separated than 3 and 5 ( Fig. 8B ). Legs long (ca 1.15 times longer than midbody height), tarsal brushes present on all legs, but less evident in ring 18, coxae and prefemora each with a conspicuous long seta ventro-apically. Femora with adenostyles in legs 4–6 such as in I. garciae n. sp. In length, prefemur = femur> tarsus> postfemur> tibia.

Gonopod ( Fig. 9 ) relatively simple. Coxite (cx) subcylindrical, with a faint, ventral, subtransverse ridge at midway, not elongate, setose ventrally in proximal zone; cannula (ca) normal, tubiform. Prefemorite (pfe) much shorter than femorite (fe), densely setose; fe clearly demarcated basally from pfe, also distally by a distofemoral sulcus (su1). sph directed medially, large, long and flattened, subcircular, apical lobe (lo) very short and marking the beginning of sheathing the sl between a lamina medialis (lm) and a lamina lateralis (ll), very evident in mesal view. lo slightly demarcated by su1 and a postfemoral sulcus (su2); lm shorter and smaller than ll; su2 marking the beginning of a flagelliform sl inside lm.

Remarks. The new species clearly falls in group V, subgroup 3c of Jeekel (1963), together with I. venezuelanus ( Verhoeff, 1938) , I. minerus n. sp. and I. florezi n. sp. sharing the gonopod sph being curved and bilobate apically to form an almost complete circle, but it differs from both former species by the apical part of the sph overlapping the lamellar processes as in I. minerus n. sp., and from the lattter species by the free lm supporting most of the sl and in the absence of k in the lateral part of the sph.

Distribution. Only known from the type locality ( Fig. 14 ).

Figures

FIGURE 8. Iulidesmus sabaneta n. sp., male holotype (MHN-UPN-MD-123). A. Habitus in dorsal view. B. Habitus in ventral view. Scale bar: 4 mm.

FIGURE 9. Left gonopod of Iulidesmus sabaneta n. sp., male holotype (MHN-UPN-MD-123). A, D. Mesal view. B, E. Ventral view. C, F. Lateral view. Abbreviations: ca: cannula, cx: coxite, fe: femorite, ll: lamina lateralis, lm: lamina medialis, lo: apical lobe, pfe: prefemorite, sl: solenomere, sph: solenophore, su1: distofemoral sulcus, su2: postfemoral sulcus. Scale bar: 0.5 mm.

FIGURE 14. Distribution map of six new species of Iulidesmus Silvestri, 1895 in Colombia.