Iulidesmus jeekeli, 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 : 70-72

Iulidesmus jeekeli new species

Figs 12–14

urn:lsid:zoobank.org:act:8C128ABC-2311-4B23-BE54-0B2EFEDE223D

Strongylosoma pulvillatum (partim): Carl, 1914: 882.

Diagnosis. The new species clearly falls into group V, subgroup 3b of Jeekel (1963), together with I. pulvillatus ( Attems, 1898) , from Paraguay, I. salvadorii ( Silvestri, 1895) , from both Salta, Argentina and Caiza, Bolivia, I. truncatus ( Schubart, 1943) , from Mato Grosso, Brazil, and I. venezuelanus ( Verhoeff, 1938) , from Venezuela, sharing the gonopodal solenophore (sph) curved to form an almost complete circle, and its apical part obliquely truncate. However, I. jeekeli n. sp. differs from the former species by the presence of a setose distodorsal tubercle on the gonocoxite (= coxite) ( Carl 1914), a non-expanded femorite (fe), evident tergal setae, and a usual cannula (ca); from I. salvadorii by the presence of a setose distodorsal tubercle on the gonopodal cx and a free lm supporting most of sl; from I. truncatus mainly by the lm being much longer and exceeding the ll in length; and from I. venezuelanus by the pfe being shorther, su2 less marked and deep, and the free lm supporting most of sl and exceeding the ll in length.

Name. The new species is dedicated to the late Casimir Albrecht Willem Jeekel (1922–2010), a great Dutch myriapodologist and entomologist known for his major contributions to the taxonomy of millipedes globally.

Material examined.

Holotype. COLOMBIA ● ♂; Cundinamarca, Viotá (4°26′N, 74°31′W), ca 1000 m asl; s.f. O. Fuhrmann leg.; (MHNG-ARTO-0034037).

Description. Length of holotype, 20 mm, width of midbody metazona, 2.1 mm. Coloration in alcohol apparently faded, likely also tanned green by the tin insect pin piercing the body, presently dark greenish yellow 103. Antennae and legs brilliant yellow 83.

Body strongylosomoid, not moniliform, with poorly developed paraterga ( Fig. 12 ). Postcollar constriction evident; in width, head = ring 3 = 4 <collum <2 <5 – 16; on rings 17 – 20, trunk tapering towards telson. Antennae long, claviform, in situ reaching the end of ring 3 ( Fig. 12 ); in length, antennomeres 4>5>3>2>6>1=7.

Paraterga set low (at about half midbody height), evidently larger on pore-bearing rings than on poreless ones, never projecting caudally past rear tergal margin, flattened and decreasing in size only from ring 18 towards telson. Transverse mid-dorsal sulci present on rings 5–18, marked, thin lines not reaching the bases of paraterga. Ozopores lateral, slightly visible 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 short setae (each ca 0.14 mm long) or their insertion points anteriorly (very evident) in one transverse row on each postcollar metatergum.

Sterna with slight transverse cross-impressions, setose, traceable sternal cones (males) very small, located between coxae 4–7 ( Fig. 12B ). Legs rather long (ca 1.06 times longer than midbody height), tarsal brushes present on all legs, but less dense in last rings, coxae and prefemora each with a conspicuous long seta ventro-apically. Femora with adenostyles on legs 4 – 7. In length, prefemur> tibia> tarsus> femur = postfemur.

Gonopod ( Fig. 13 ) relatively simple. Coxite (cx) subcylindrical, with a faint, ventral, subtransverse ridge at midway, elongate, setose ventrally; cannula (ca) normal. Prefemorite (pfe) shorter than femorite (fe), densely setose as usual; fe clearly demarcated from pfe basally, but distally only very slightly by a distofemoral sulcus (su1). sph directed medially, large, long and almost fully flattened, subcircular; apical lobe (lo) shorter and not too pronounced, slightly delimited by su1 and very clearly by su2. lm acuminate, slender and large, surpassing even ll apically in ventroposterior view, supporting most of solenomere (sl); ll emarginate, longer and larger.

Remarks. In addition to Carl’s (1914) false record of I. pulvillatus from Colombia (see above), which is here described as a new species, I. jeekeli n. sp., we have also come across some more inconsistencies. That false record was said to be based on a male and a female coming from a single locality, but, when revising the material borrowed from the Geneva Museum, we found two males instead: MHNG-ARTO-0034037 and MHNG-ARTO-0032168. Either the female could have been replaced by another male or Carl (1914) simply mistook the sex. The study of the second male, especially its gonopods, is deferred for a later project. As the gonopods of the current holotype have been removed and studied by Carl (1914), while the second male with its gonopods remains intact, we prefer to restrict our paper to what it is now.

In addition, the label underlying the specimens raises some doubts as well, since the locality for both males is referred to as “ Colombie coll. Fuhrmann ”, but neither is further precised to Carl’s (1914) published record from “Buenavista near Viotá, Cundinamarca ”; however, this locality currently corresponds to Viotá, Cundinamarca, and is regarded here as the type locality of I. jeekeli n. sp. (MHNG-ARTO-0034037). The provenance of the second male, (MHNG-ARTO-0032168), as well as the specimen itself, still require further research.

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

Figures

FIGURE 12. Iulidesmus jeekeli n. sp., male holotype (MHNG-ARTO-0034037). A. Habitus in dorsolateral view. B. Habitus in ventrolateral view. Scale bar: 4 mm. Photographs taken by Christina Lehmann-Graber (MHNG).

FIGURE 13. Gonopods of Iulidesmus jeekeli n. sp., male holotype (MHNG-ARTO-0034037). A, D. Mesal view of right gonopod. B, E. Posteroventral view of right gonopod. C, F. Lateral view of left gonopod. 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. Photographs taken by Christina Lehmann-Graber (MHNG).

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