Hemisphaeroparia longibrachiata, Golovatch, Sergei I., Fiemapong, Armand Richard Nzoko & VandenSpiegel, Didier, 2019

Golovatch, Sergei I., Fiemapong, Armand Richard Nzoko & VandenSpiegel, Didier, 2019, Trichopolydesmidae from Cameroon, 2: A species-level reclassification of Afrotropical trichopolydesmids (Diplopoda, Polydesmida), with two new species and two new records from Cameroon, and two new species from the Nimba Mountains, Guinea, ZooKeys 891, pp. 31-59 : 31

Hemisphaeroparia longibrachiata sp. nov. Figs 1E , 10 , 11

Type material.

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.

Diagnosis.

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.

Name.

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

Description.

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. 10 A–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. 10 D–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.

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.

Figures

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.

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)

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).