Moojenodesmus simplex, Golovatch, 2024

Golovatch, S. I., 2024, Five new species of the millipede family Trichopolydesmidae from Peru (Diplopoda: Polydesmida), Arthropoda Selecta 33 (1), pp. 1-13 : 3-4

Moojenodesmus simplex sp.n.

Figs 1–4 .

HOLOTYPE ♂ ( ZMUM), Peru, Junin Region, Satipo , S 11°15′15″, W °38′17″, fruit orchard, under wooden planks and stones, 21.IX.2017, K.Yu. Eskov leg.

NAME. To emphasize the unusually simple gonopods.

DIAGNOSIS. Differs from all 10 or 11 presently recognized congeners by the unusually simple gonopods ( Fig. 4 ), which are basically sac-shaped, squarish and totally devoid of considerable outgrowths, and showing subequally high coxite (cx) and telopodite (te), the latter with only a rudimentary solenomere (sl) that terminates a straight, fully mesal seminal groove (sg).

DESCRIPTION. Length ca 10.5 mm, width of midbody pro- and metazonae 0.45 and 0.65 mm, respectively (♂). Colouration in alcohol uniformly light brown with lighter grey-brown paraterga and legs ( Figs 1–3 ). Body with 20 segments. Tegument moderately shining, texture very delicately shagreened. Head unmodified, clypeolabral region very finely and densely pilose, vertex and occiput bare, genae squarish.Antennae medium-sized, clearly clavate due to highest antennomere 6 (height measured from the lower to the higher edge) ( Figs 1–3 ), in situ reaching past ring 2 dorsally (♂).

In width, collum << head <ring 2 = 3 <4 <5=15, thereafter body gradually tapering towards telson ( Fig. 1 ). Paraterga strongly developed, set high (at about upper ¼ midbody height), starting with collum, mostly subhorizontal, leaving dorsum largely slightly convex. Caudolateral corner of paraterga spiniform, postcollum ones extending increasingly past rear tergal margin, especially clearly so in rings 17 and 18. All poreless segments with two, all pore-bearing ones with three, minute, barely visible, setigerous incisions at lateral margin. Front margins of metaterga very narrowly bordered and forming distinct shoulders. Pore formula normal, ozopores evident pits, fully dorsal, located behind posteriormost marginal indentation at about caudal ¼ poriferous metaterga. Metatergal sculpture typical, poorly-developed, obliterate, with three transverse rows of typical (= polydesmid), setigerous, polygonal bosses ( Figs 1–3 ). Tergal setae very short, slightly longer only on collum, simple, usually sharpened at tip, often obliterate. Stricture between pro- and metazona wide, shallow and nearly smooth. Limbus very thin and microdenticulate. Pleurosternal carinae absent. Epiproct rather short, conical, pre-apical lateral papillae very small ( Figs 1, 3 ). Hypoproct semi-circular; caudal, paramedian, setigerous papillae very distinct and well-separated cones ( Fig. 3 ). Sterna without modifications, setose. Legs (♂) generally rather long and slender ( Figs 1–3 ), ca 1.7–1.8 times as long as midbody height, very densely setose, almost all setae being simple; prefemora slender, devoid of lateral bulges ( Fig. 3 ). In length, tarsus = femur> prefemur> postfemur = tibia> coxa ( Fig. 3 ).

Gonopods ( Fig. 4 ) with large, subquadrate and transverse coxites (cx) strongly fused medially at base and carrying a few long setae ventrally; a long, simple and unciform cannula (ca) as usual. Telopodite (te) only slightly stouter than cx, also subquadrate, prefemorite (= densely setose part) much shorter than both cx and te; seminal groove (sg) running over most of te extent on mesal side alone, straight, terminating on a very small solenomere (sl).

Figures

Figs 1–3. Moojenodesmus simplex sp.n., ♂ holotype, habitus, dorsal, lateral and ventral views, respectively. Photographs by K.V. Makarov, taken not to scale. Рис. 1–3. Moojenodesmus simplex sp.n., голотип ♂, обЩий вид, соответственно сверху, сбоку и сниЗу.Фотографии К.В. Макарова, снЯты беЗ масштаба.

Fig. 4. Moojenodesmus simplex sp.n., ♂ holotype, right gonopod, caudal view. Abbreviations: ca — cannula; cx — coxite, sg — seminal groove; sl — solenomere; te — telopodite. Scale bar: 0.2 mm. Рис. 4. Moojenodesmus simplex sp.n., голотип ♂, правый гонопод, сЗади. ОбоЗначениЯ: ca — канюлЯ; cx — коксит; sg — семенной канал; sl — соленомер; te — телоподит. Масштаб: 0,2 мм.