Holotype ♂ (MRAC 22840), Guinea, Nimba Mountains, summit of Mount Nion, ca 1405 m a.s.l., forest litter, 28.V.2019, A. Henrard, D. VandenSpiegel, C. Allard et al. leg. (Nimba 2019-24). Paratypes: 1 ♂ (MRAC 22841), 9 ♀ (MRAC 22852), 1 ♂ (SEM, MRAC 22842), same locality and date, together with holotype.

Differs from all other species of the genus by the unusually complex gonopodal structure, i.e. the presence of a particularly prominent, distolateral, gonocoxal lobe (lo) that protects a similarly clearly exposed telopodite, the latter being largely represented by a high apicomesal lobe/outgrowth (ab) that carries a highly peculiar, large, tube-shaped solenomere (tu). The gonocoel is shallow and conceals only the bases of the telopodites (Figs 2K, 3).

To emphasize the complex gonopodal structure; adjective in feminine gender.

Length of holotype ca 5 mm (♂), width of midbody pro- and metazonae 0.5 and 0.7 mm (♂), respectively. Length of paratypes ca 5 mm (♂) or 6–7 mm (♀), width of midbody pro- and metazonae 0.5 and 0.7 mm (♂) or 0.6–0.7 and 0.8–1.0 mm (♀), respectively. Coloration in alcohol marbled light or darker reddish brown, venter and legs light brown to nearly pallid (Fig. 1A).

Figure 1. 

Habituses of A Physetoparia complexa sp. nov., ♂ holotype, lateral view B, C Bactrodesmus grandis sp. nov., ♂ paratype, lateral view of entire animal and its anterior body half, ventral view D Hemisphaeroparia parvula (Porat, 1894), both ♀ syntypes, lateral, subventral or sublateral view E Hemisphaeroparia longibrachiata sp. nov., ♂ holotype, dorsal view F Hemisphaeroparia avis sp. nov., ♂ paratype, lateral view. Scale bars: 1.0 mm.

Body with 20 segments in both sexes. Tegument very delicately micro-alveolate, mainly slightly shining. Head densely micropilose, devoid of epicranial modifications (Fig. 2A, B, E). Interantennal isthmus almost two times diameter of antennal socket. Antennae long and strongly clavate, reaching back past segment 3 when stretched dorsally. In length, antennomere 3 = 6 > 2 = 5 > 1 = 4 =7; antennomere 6 the largest, antennomeres 5 and 6 each with a distinct, round, distodorsal field of sensilla. In width, collum < head < segments 2–4 < 5–16; thereafter body gradually tapering towards telson. Collum ellipsoid, transversely oval, like all following metaterga with three transverse, regular rows of setae on low, but evident, setigerous bosses. Tergal setae medium-sized, each ca 1/4–1/5 as long as metatergum, bacilliform and longitudinally ribbed, gradually growing longer towards telson, set on minute knobs (Fig. 2A–J), always 3+3 in each row on postcollum metaterga; 2–3 additional setae normally present at lateral margin of paraterga. A faint, sinuate, transverse sulcus visible behind first row on most metaterga. Dorsum invariably regularly convex. Paraterga medium-sized, set at around upper 1/3 of metazonae (Fig. 2A–H), visible starting with collum, often slightly upturned caudally, faintly, but regularly rounded and bordered, lateral incisions almost absent. Caudal corner of paraterga mostly rounded, sharply truncate only in a few caudal segments (Fig. 2D, G). Pore formula normal: 5, 7, 9, 10, 12, 13, 15–19. Ozopores small, round, opening flush dorsally near caudal corner of poriferous paraterga. Stricture between pro- and metazonae wide, shallow. Limbus very finely microspiculate. All spiracles usual, simple. Pleurosternal carinae traceable as very faint lines on most segments (Fig. 2B, D). Epiproct short, conical, flattened dorsoventrally. Hypoproct semi-circular, setae strongly separated and borne on minute knobs.

Figure 2. 

Physetoparia complexa sp. nov., SEM micrographs of ♂ paratype A habitus, lateral view B, E anterior part of body, lateral and dorsofrontal views, respectively C, F midbody segments, lateral and dorsal views, respectively D, G posterior part of body, lateral and dorsal views, respectively H cross-section of a midbody segment, caudal view I fine tergal structure, dorsal view J tergal seta, lateral view K gonopodal coxa in situ, lateral view. Scale bars: 0.5 mm (A), 0.1 mm (B–H), 0.05 mm (I, K), 0.01 mm (J).

Sterna wide, unmodified, setose. Legs rather long and slender, ca 1.2–1.3 (♂) or 1.0–1.1 (♀) times as long as midbody height; in length, tarsus > femur > prefemur > coxa = postfemur = tibia, the latter with a particularly long, tactile seta apicodorsally. Tarsal brushes absent.

Gonopods (Fig. 3) with large, subglobose, barely setose coxae, fused medially at base, each coxa carrying a very prominent, rounded, distolateral lobe (lo) and two very strong setae near place of fusion. Telopodites very clearly exposed, but strongly protected by lo, bases only a little concealed inside a shallow gonocoel. Telopodites only slightly shorter than lo, each with only a single, large, subsecuriform, lobe-shaped, apicomesal branch/outgrowth (ab) showing a microdentate apical margin, a peculiar tube (tu) with a large orifice (or), and a field of fimbriae at base of tu, both hidden between lo and ap; tu apparently functioning as a solenomere.

Figure 3. 

Physetoparia complexa sp. nov., gonopods of ♂ paratypes A, B left gonopod, lateral and ventrolateral views, respectively C right gonopod, ventrocaudal view D, E right gonopod, lateral and mesal views, respectively. Abbreviations: lo distolateral lobe of coxa, ab apicomesal branch/outgrowth of telopodite, tu tube/solenomere between lo and ab with a broad orifice (or) and a field of filaments (fi) at base.Scale bars: 0.05 mm.

This new species shows several clear-cut apomorphies in gonopodal characters (see Diagnosis above), but on balance it fits quite well the scope of Physetoparia as outlined by Golovatch et al. (2018). Especially distinct similarities concern the sole congener that has a marked apicolateral outgrowth/lobe on the gonopodal coxa to protect a likewise well exposed telopodite: P. villiersi (Schubart, 1955). However, the gonotelopodite in the latter species is tripartite, including a finger-shaped solenomere, while the coxal lobe is much smaller and less conspicuous (Schubart 1955). In addition, both these species compared come from the same area, the Nimba Mountains which are shared by Liberia, Guinea and Côte d’Ivoire.

Bactrodesmus claviger Cook, 1896, by subsequent monotypy, Liberia.

As reiterated recently (Golovatch et al. 2018), this genus was first proposed as a nomen nudum (Cook 1896a), but then properly typified (Cook 1896b). The sole useful information contained in the original description of B. claviger, which was accompanied by no illustrations, concerns its small size (7 mm long, 1 mm wide), typically micropolydesmid facies (small paraterga, large and clubbed tergal setae arranged in three transverse rows etc.), strongly enlarged gonocoxae that fully conceal the telopodites and, above all, ♂ legs 2, especially their tibiae, greatly enlarged compared to others (Cook 1896b). No number of body segments has been given.

Below we put on record a new Bactrodesmus coming from the Guinean portion of the Nimba Mountains. This allows us to unequivocally clarify the identity of the genus and provide a new diagnosis.

At least ♂ tibiae 2, as well as both gonopodal coxae and gonocoel hypertrophied, telopodites being strongly sunken and their distal outgrowths remaining nearly fully concealed inside gonocoel. Only one prominent, basal fold/branch (bb = sp) present, albeit fully concealed as well; a simple and short solenomere branch (sl) protected by bb mesally and by a clearly 2-segmented lateral part laterally.

This genus is presumably among the most advanced representatives of Afrotropical Trichopolydesmidae in showing several autapomorphies.

Holotype ♂ (MRAC 22843), Guinea, Nimba Mountains, near cave 2, Serengbara, camp 3, ca 1035 m a.s.l., litter, 2.V.2019, A. Henrard, D. VandenSpiegel, C. Allard et al. leg. (Nimba 2019-41). Paratypes: 1 ♀ (MRAC 22844), same locality, together with holotype: 2 ♂, 1 ♀ (MRAC 22845), 2 ♂ (MRAC 22862), 1 ♂ (SEM, MRAC 22846), 1 ♂ (ZMUM Rd 4628), same locality, forest; ca 975 m a.s.l., 2.V.2019, A. Henrard, D. VandenSpiegel, C. Allard et al. leg. (Nimba 2019-49).

Differs from both other species of the genus by ♂ legs 1–3 being clearly enlarged and modified, vs. ♂ legs 2 or 2 and 3, from B. bicornis also by three (vs. two) transverse rows of tergal setae and the collum which is narrower than the head, from B. claviger by the considerably larger body.

To emphasize the relatively large body and clearly enlarged ♂ legs 1–3; adjective.

Length ca 8 (♂, including holotype) or 9 mm (♀), width of midbody pro- and metazonae 1.0 and 1.3 mm (♂, including holotype) or 1.2 and 1.5 mm (♀), respectively. Coloration in alcohol marbled light brown to reddish brown, venter and legs usually lighter, light grey-brown to nearly pallid (Fig. 1B, C).

Body with 20 segments in both sexes. Tegument very delicately micro-alveolate, mainly slightly shining. Head densely micropilose, devoid of epicranial modifications, but genae roundly squarish and very strongly swollen laterally; gnathochilarium without modifications (Fig. 4G). Interantennal isthmus 1.8 times diameter of antennal socket. Antennae long and strongly clavate, reaching back past segment 3 (♂) when stretched dorsally. In length, antennomere 3 = 6 > 5 > 2 = 4 > 7 > 1; antennomere 6 the largest, antennomeres 5 and 6 each with a distinct, round, distodorsal field of minute sensilla. In width, collum < segments 2 and 3 < head = 4 < 5–16; thereafter body gradually tapering towards telson. Collum ellipsoid, transversely oval, like all following metaterga with three transverse, regular rows of setae. Tergal setae largely abraded, medium-sized, each ca 1/4–1/5 as long as metatergum, bacilliform and longitudinally ribbed, set on minute knobs, growing slightly longer toward telson, 3–4 additional setae present at lateral margin of paraterga (Fig. 4A–E, H), always 3+3 in each row on postcollum metaterga. Dorsal surface of metaterga nearly smooth, regularly convex. Paraterga medium-sized, set at around upper 1/3 of metazonae (Fig. 4A–C, E, H), visible starting with collum, often slightly upturned caudally, faintly, but regularly rounded and bordered, lateral incisions absent, with minute setigerous knobs present in their stead, including ones located at caudal corners. Paraterga 2 slightly enlarged, more strongly declined and broadly rounded compared to following ones (Fig. 4A). Starting with paraterga 5 or 6, caudal corner increasingly sharp and drawn back past rear tergal margin (Fig. 4A–C, H). Pore formula normal: 5, 7, 9, 10, 12, 13, 15–19. Ozopores small, round, opening flush dorsally near caudal corner of poriferous paraterga. Stricture between pro- and metazonae wide, shallow. Limbus very finely microspiculate. Spiracles very small, located on short cones (Fig. 4K). Pleurosternal carinae traceable as very faint ridges or lines on most segments (Fig. 4A, B). Epiproct short, conical, flattened dorsoventrally. Hypoproct semi-circular, setae strongly separated and borne on minute knobs.

Figure 4. 

Bactrodesmus grandis sp. nov., SEM micrographs of a ♂ paratype A anterior part of body, lateral view B–D midbody segments, lateral, dorsal and ventral views, respectively E cross-section of a midbody segment, caudal view F fine tergal structure, dorsal view G head, ventral view H midbody paratergum, lateral view I from right to left, legs 1–3 in situ, lateral view J leg-pair 1, oral view K leg 2 and base of leg 3, frontoventral view L coxae 2, subventral view M leg 3 and bases of several following legs, frontoventral view. Scale bars: 0.2 mm (A–E), 0.1 mm (G, I–K, M), 0.05 mm (I, L), 0.02 mm (F).

Sterna wide, unmodified, setose. Legs rather long and slender, ca 1.3–1.4 (♂) or 1.1–1.2 times (♀) as long as midbody height; in length, tarsus > femur > prefemur > coxa = postfemur = tibia. Tarsal brushes present only on ♂ legs 1 and 2; ♂ legs 1–3 conspicuously enlarged (Fig. 4I): legs 1 (Fig. 4J) with increasingly inflated pretarsal podomeres; legs 2 (Fig. 4K, L) with each coxa caudally supplied with what seems to be a gland whose wide orifice is surrounded by a whorl of setae while the interior carries bundles of abundant, very long, sharp, distally entangled filaments; tibiae 2 particularly strongly swollen, while tarsi 2 somewhat shortened, dorsally flattened and spoon-shaped; legs 3 (Fig. 4K, M) resembling legs 1, but their prefemora and femora especially densely setose ventrally.

Gonopods (Fig. 5) complex, with particularly strongly enlarged, globose and nearly smooth coxae (cx), both forming a very deep gonocoel, both clearly rimmed apically and with 2+2 especially strong setae mediobasally near place of coxal fusion; one small rounded lobe each present on cx distolaterally (lol) and distomesally (lom); cannulae relatively small, as usual. Telopodites deeply sunken inside gonocoel, very poorly exposed beyond it, each starting with a setose funnel-shaped part (fu) marking the orifice for the cannula to enter and the beginning of a seminal groove, the latter quickly passing onto a short, stout, slightly curved, distad attenuating solenomere (sl) branch fully concealed inside gonocoel; basal part of telopodite extended mesally along fu into a distinct fold turning apically into a long, gently and regularly curved, laterad directed spine (sp); lateral part of telopodite divided distally by a clear-cut suture (su) into two sections, both being simple and stout slabs, but distal one bearing a meso-central membranous sac to protect sl tip.

Figure 5. 

Bactrodesmus grandis sp. nov., gonopods of ♂ paratypes A, B left gonopod, subventral and ventromesal views, respectively C, D right gonopod, ventrolateral and ventral views, respectively E, F right gonopod, lateral and mesal views, respectively. Abbreviations: cx coxa, lol distolateral lobe of coxa, lom distomesal lobe of coxa, fu basal funnel of telopodite, sl solenomere, sp spine, su parabasal sulcus on telopodite. Scale bars: 0.1 mm.

The size, external structures and gonopodal conformation of B. grandis sp. nov. match closely those as described and depicted for B. bicornis by Demange and Mauriès (1975). The latter species is 8.0 mm long and 1.5 mm wide. Its hypertrophied gonopodal coxa is likewise nearly smooth and shows two small distal lobes, lol and lom. The short spiniform solenomere (sl), the long mesobasal spine (sp) and the two-segmented lateral part of the gonotelopodite look much like, and are located similarly in B. grandis sp. nov. Unfortunately, even though the gonopodal structure of B. claviger remains unknown, the genus Bactrodesmus can presently be redefined (see above).

Syntypes 2 ♀ (NHRM-GULI000069465), Kamerun, Yngve Sjöstedt leg.

Porat (1894) described this species, based on two syntypes deriving from an unspecified locality in Cameroon. We have revised both syntypes and found them to be adult females, one incomplete, the other one complete and with 20 segments (Fig. 1D). Since Cameroon appears to support solely species of the trichopolydesmid genus Hemisphaeroparia (24 at the moment), we tentatively transfer the above species to Hemisphaeroparia, comb. nov., even though the spiracles located next to coxa 1 or 2 are not enlarged (Fig. 1D). Characteristically enlarged spiracles 1 appear to be restricted to far from all species of Hemisphaeroparia (see below under H. spiniger). We doubt though that the identity of this enigmatic species will ever be properly established, as superficially the females of most species of Trichopolydesmidae look very much alike. Only the everted vulvae of one of the syntypes might be helpful in the future, but first their comparative study must be accomplished.

1 ♂ (MRAC 22847), 1 ♂ (SEM, MRAC 22848), Cameroon, Center Region, Mafou and Afamba Division, Mfou, cocoa plantation, 3°48’49.6”N, 11°40’49.6”E, 24.VII.2019, A.R. Nzoko Fiemapong leg.

The new samples fully agree with the original description (Golovatch et al. 2018) and are again illustrated not only to confirm the species’ identity (Figs 6, 7), including the unique, conspicuous, epicranial bundles of long filaments on the ♂ head (Fig. 6D, J), but also to note the presence of a marked ventrobasal process on each ♂ prefemur 1 (Fig. 6L), which is much like the one observed in H. avis sp. nov.

Figure 6. 

Hemisphaeroparia falcata Golovatch, Nzoko Fiemapong, Tamesse, Mauriès & VandenSpiegel, 2018, SEM micrographs of ♂ from Mfou A, D, G anterior part of body, lateral, ventral and dorsal views, respectively B, E, H midbody segments, lateral, ventral and dorsal views, respectively C, F, I posterior part of body, lateral, ventral and dorsal views, respectively J epicranial bundles of filaments, dorsal view K fine tergal structure with setae, dorsal view L anterior legs with a triangular ventral process on prefemur 1, lateral view. Scale bars: 0.1 mm (A–I), 0.05 mm (L), 0.02 mm (K), 0.01 mm (J).

Figure 7. 

Hemisphaeroparia falcata Golovatch, Nzoko Fiemapong, Tamesse, Mauriès & VandenSpiegel, 2018, gonopods of ♂♂ from Mfou A both gonopods in situ, ventral view B–E left gonopod in various views F right gonopod, caudal view. Scale bars: 0.05 mm (A, F), 0.02 mm (B–E).

The new locality, Mfou, lies quite close to the type one, Awae, both in the Central Region of Cameroon. Because Awae represents a native woodland habitat, H. falcata might have been introduced to the cocoa plantation at Mfou.

1 ♂ (MRAC 22860), 1 ♂ (SEM, MRAC 22861), Cameroon, Center Region, Mafou and Afamba Division, Mfou, cocoa plantation, 3°48’49.6”N, 11°40’49.6”E, 24.VII.2019, A.R. Nzoko Fiemapong leg.

The new samples fully agree with the original description (Golovatch et al. 2018) and are again illustrated to confirm the species’ identity (Figs 8, 9), including the remarkably enlarged spiracles 1.

Figure 8. 

Hemisphaeroparia spiniger Golovatch, Nzoko Fiemapong, Tamesse, Mauriès & VandenSpiegel, 2018, SEM micrographs of ♂ from Mfou A, D, G anterior part of body, lateral, dorsal and ventral views, respectively B, E, I midbody segments, lateral, dorsal and ventral views, respectively C, F, J posterior part of body, lateral, dorsal and ventral views, respectively H, L enlarged spiracles near coxae 2, ventral view K cross-section of a midbody segment, caudal view M fine tergal structure with setae, dorsal view N tergal seta, enlarged. Scale bars: 0.1 mm (A–G, I–K), 0.05 mm (H, M), 0.02 mm (L), 0.01 mm (N).

Figure 9. 

Hemisphaeroparia spiniger Golovatch, Nzoko Fiemapong, Tamesse, Mauriès & VandenSpiegel, 2018, gonopods of ♂♂ from Mfou A both gonopods in situ, ventral view B, C right gonopod, caudolateral and subcaudal views, respectively D left gonopod, mesal view. Scale bars: 0.1 mm (D), 0.05 mm (A–C).

The new locality, Mfou, lies quite close to the type one, campus of University Yaounde 1, both in the Central Region of Cameroon. Moreover, because both known localities/habitats represent artificial palm or cocoa plantations, H. spiniger could have been introduced there from some native woodlands still to be revealed or already vanished.

Holotype ♂ (MRAC 22857), Cameroon, West Region, Haut-Nkam Division; sacred forest, 5,313712N, 10,250323E, 28.V.2019, A.R. Nzoko Fiemapong leg.

Paratypes , 2 ♂, 2 ♀, 1 ♀ fragment (MRAC 22858), 1 ♂ (SEM, MRAC 22859), 1 ♂ (UY1), 1 ♂ (ZMUM Rd 4629), same locality, together with holotype.

Differs from all other species of the genus by the presence of only 19 segments in both sexes, coupled with a distinct, central, setose pit with two paramedian pores at the bottom in the ♂ epicranium, and the particularly long, falcate, fully exposed branch/process ab on the gonopodal telopodite.

To emphasize the particularly long branch/process ab on the gonopodal telopodite; adjective in feminine gender.

Length of holotype ca 4 mm (♂), width of midbody pro- and metazonae 0.3 and 0.5 mm (♂), respectively. Length of paratypes 4–5 mm, width of midbody pro- and metazonae 0.3–0.4 and 0.5–0.6 mm (♂, ♀), respectively. Coloration in alcohol faintly marbled, light brown to brown, venter and legs light grey-brown (Fig. 1E).

Body with 19 segments in both sexes. Tegument very delicately micro-alveolate, mainly slightly shining. Head very densely micropilose, ♂ epicranium slightly elevated and supplied with a very distinct, central, oval, densely setose pit with two paramedian pores (Fig. 10G, K). Interantennal isthmus almost three times diameter of antennal socket. Antennae long and strongly clavate, reaching back past segment 4 (♂) or 3 (♀) when stretched dorsally. In length, antennomere 3 = 6 > 5 > 2 = 4 > 7 > 1; antennomere 6 the largest, antennomeres 5 and 6 each with a distinct, round, distodorsal field of sensilla. In width, segments 5–15 >2 > head = segments 3 and 4 > collum; body gradually tapering towards telson on segments 16–19. Collum ellipsoid, transversely oval, like all following metaterga with three transverse, regular rows of setae; anterior row composed of somewhat longer setae. Tergal setae medium-sized, each ca 1/5 as long as metatergum, bacilliform and longitudinally ribbed (Fig. 10A–E, I, M), always 3+3 in each row on postcollum metaterga; 2–3 additional setae at lateral margin of paraterga. Dorsum invariably regularly convex. Paraterga medium-sized, set at around upper 1/3 of metazonae (Fig. 10D–F), visible starting with collum, regularly rounded, lateral incisions absent. Caudal corner of paraterga mostly rounded, drawn back past rear tergal margin only on segments 16 and 17 (Fig. 10C, E). Pore formula normal: 5, 7, 9, 10, 12, 13, 15–18. Ozopores small, round, opening flush dorsally near caudal corner of poriferous paraterga. Stricture between pro- and metazonae wide, shallow. Limbus very finely microspiculate. Spiracles very small, as usual. Pleurosternal carinae traceable as very faint ridges or lines on most segments (Fig. 10D, E). Epiproct short, conical, flattened dorsoventrally. Hypoproct semi-circular, setae strongly separated and borne on minute knobs.

Figure 10. 

Hemisphaeroparia longibrachiata sp. nov., SEM micrographs of a ♂ paratype A, G anterior part of body, dorsal and ventral views, respectively B, D, H midbody segments, dorsal, lateral and ventral views, respectively C, E, I posterior part of body, dorsal, lateral and ventral views, respectively F cross-section of a midbody segment, caudal view J fine tergal structure with setae, dorsal view K epicranial pit, dorsal view L leg 2 with gonopore on coxa M limbus and tergal seta, enlarged. Scale bars: 0.1 mm (A–G, I–K), 0.05 mm (H, M), 0.02 mm (L), 0.01 mm (N)

Sterna wide, unmodified, setose. Legs rather long and slender, ca 1.2–1.3 (♂) or 1.0–1.1 (♀) times as long as midbody height; in length, tarsus > femur > coxa = prefemur = postfemur = tibia, the latter with a particularly long, tactile seta apicodorsally. Tarsal brushes absent.

Gonopods (Fig. 11) with large, subglobose, clearly exposed, alveolate coxae, these rather densely setose nearly throughout, fused medially at base, each carrying two very long setae near place of fusion. Telopodites largely well exposed beyond a moderately deep gonocoel, each with two low bulges basal to anterior branch (ab), the latter extremely long, slightly coiled in basal third, falcate, gradually attenuating towards a narrowly rounded tip. No solenomere discernible at base of ab.

Figure 11. 

Hemisphaeroparia longibrachiata sp. nov., gonopods of ♂ paratypes A both gonopods in situ, ventral view B, C left gonopod, caudolateral and subcaudal views, respectively D right gonopod, mesal view. Abbreviation: ab apical branch. Scale bars: 0.1 mm (D), 0.05 mm (A–C).

Holotype ♂ (MRAC 22853), Cameroon, Center Region, Mafou and Afamba Division, Mfou, cocoa plantation, 3°48’49.6”N, 11°40’49.6”E, 24.VII.2019, A.R. Nzoko Fiemapong leg. Paratypes: 3 ♂, 12 ♀, 2 subadult ♀ (many fragmented) (MRAC 22854), 12 ♂ (MRAC 22855), 1 ♂ (SEM, MRAC 22856), 1 ♂, 1 ♀ (ZMUM Rd 4630), 1 ♂ (UY1), same locality, together with holotype.

Diagnosis. Differs from all other species of the genus by the presence of a boletiform epicranial tubercle (♂) (Fig. 12D, K), coupled with the unusually large, disc-shaped spiracles next to coxae 1 or 2 (Fig. 12G, L), the strong, setose, subtriangular, distoventral process on ♂ prefemur (Fig. 12J), the densely setose sterna between ♂ coxae 2 and 3 (Fig. 12M), and the sole prominent, clearly exposed process (ab) with a bird’s beak-shaped tip on the gonopodal telopodite (Fig. 13).

Figure 12. 

Hemisphaeroparia avis sp. nov., SEM micrographs of a ♂ paratype A, D, G anterior part of body, lateral, dorsal and ventral views, respectively B, E, H midbody segments, lateral, dorsal and ventral views, respectively C, F, I posterior part of body, lateral, dorsal and ventral views, respectively J telopodite 1 with a prominent process in prefemur K, L epicranial tubercle M densely setose sterna between coxae 2 and 3 N fine tergal structure with limbus and setae, dorsal view. Scale bars: 0.1 mm (A–I), 0.05 mm (J, K, M), 0.02 mm (L, N).

Figure 13. 

Hemisphaeroparia avis sp. nov., gonopods of ♂ paratypes A both gonopods in situ, ventral view B–D right gonopod, ventrocaudal, lateral and mesal views, respectively. Abbreviations: ab apical branch, sl solenomere. Scale bars: 0.1 mm (A, C, D), 0.05 mm (B).

Name. From Latin avis (= bird), to emphasize the bird’s beak-shaped tip of the sole process (ab) of the gonopodal telopodite; noun in apposition.

Description. Length of holotype ca 4.5 mm, width of midbody pro- and metazonae 0.45 and 0.6 mm (♂), respectively. Length of paratypes 4.0–5.5 mm, width of midbody pro- and metazonae 0.45–0.5 and 0.6–0.7 (♂) or 0.6–0.8 mm (♀), respectively. Coloration in alcohol mostly uniformly reddish, apparently in part due to a thin earth crust coating most of the body (Fig. 1F); more rarely nearly pallid.

Body with 20 segments in both sexes. Tegument very delicately micro-alveolate, slightly shining to dull. Head very densely micropilose, with a very distinct, mushroom-like, frontal tubercle (♂) (Fig. 12D, K). Interantennal isthmus ca 1.3–1.4 times diameter of antennal socket. Antennae long and strongly clavate, reaching back up to segment 3 when stretched dorsally (♂, ♀). In length, antennomere 3 = 6 > 5 > 2 = 4 > 7 > 1; antennomere 6 the largest, antennomeres 5 and 6 each with a distinct, round, distodorsal field of minute sensilla. In width, collum < head < segments 2–4 < 5–16; thereafter body gradually tapering towards telson. Collum ellipsoid, transversely oval, like all following metaterga with three transverse, regular rows of setae. Tergal setae relatively long, each mostly ca 1/3–1.4 as long as metatergum, a little longer on collum and gradually reduced in size towards telson, bacilliform and longitudinally ribbed (Fig. 12A–F, N), always 3+3 in each row on postcollum metaterga. Dorsum invariably regularly convex. Paraterga medium-sized, set at around upper 1/3 of metazonae (Fig. 12A–C), visible starting with collum, often slightly upturned caudally, faintly, but regularly rounded and bordered, lateral incisions absent; but 2–3 setae or their insertion points present at lateral margin. Caudal corner of paraterga mostly rounded, drawn increasingly back, but faintly reaching past rear tergal margin only on segments 18 and 19 (Fig. 12C, F). Pore formula normal: 5, 7, 9, 10, 12, 13, 15–18. Ozopores small, round, opening flush dorsally near caudal corner of poriferous paraterga. Stricture between pro- and metazonae wide, shallow. Limbus very finely microspiculate. Spiracles next to coxae 1 or 2 unusually prominent, discoid and microporose (Fig. 12G, L); following ones small, inconspicuous, as usual. Pleurosternal carinae traceable as very faint ridges or lines on most segments (Fig. 12A–C). Epiproct short, conical, flattened dorsoventrally. Hypoproct semi-circular, setae strongly separated and borne on minute knobs.

Sterna wide, mostly unmodified and sparsely setose, unusually densely setose only between ♂ coxae 2 and 3 (Fig. 12M); each ♂ prefemur 1 with a prominent, densely setose, subtriangular, blunt, distoventral process (Fig. 12J) (much like in H. falcata); some setae on ♂ legs slightly modified, with flattened or branching tips. Legs rather long and slender, ca 1.2–1.3 (♂) or 1.0 –1.1 (♀) times as long as midbody height; in length, tarsus > femur > coxa = prefemur = postfemur = tibia, the latter with a particularly long, tactile seta apicodorsally. Tarsal brushes absent.

Gonopods (Fig. 13) with large, subglobose, clearly exposed, alveolate coxae, these rather densely setose nearly throughout, fused medially at base, each carrying two very long setae near place of fusion. Telopodite bases clearly concealed inside a large gonocoel, each very densely setose along funnel-shaped mesal part, with only one strong, slightly curved, very distinctly exposed, ribbon-shaped, apically bird’s beak-shaped branch (ab). Solenomere (sl) a short unciform branch located at and hidden by base of ab.

Mfou, the type locality of Hemisphaeroparia avis sp. nov., is shared with as many as further two congeners, H. spiniger and H. falcata.

Trichozonus escalerae Carl, 1905, the type species by monotypy, Equatorial Guinea (Carl 1905).

Female. 20 segments, body length 8 mm; paraterga modest, tergal setae long and bacilliform.

This genus is bound to remain dubious until a male topotypic sample from Fernando Po becomes available for study. The only other trichopolydesmid known from Fernando Po is Dendrobrachypus pusillus Verhoeff, 1941 (= Mecistoparia pusilla), which is only 5.0–5.5 mm long (Verhoeff 1941). Mauriès and Heymer (1996) tentatively synonymized Trichozonus with Physetoparia.