Polydrepanum spinatum Muhsina & Sudhikumar, 2025

Muhsina, Othayoth Musthafa, Misal, Pooja Kumar, Kalawate, Aparna Sureshchandra & Sudhikumar, Ambalaparambil Vasu, 2025, Two new species of the Indian millipede genus Polydrepanum Carl, 1932 (Diplopoda, Polydesmida, Paradoxosomatidae), Zootaxa 5642 (1), pp. 29-40 : 34-38

publication ID	https://doi.org/10.11646/zootaxa.5642.1.3
publication LSID	lsid:zoobank.org:pub:95E33544-2FA5-4041-8C54-2A18270CDC54
DOI	https://doi.org/10.5281/zenodo.15584811
persistent identifier	https://treatment.plazi.org/id/AB209B23-FFE3-FFA8-FF10-FAEAFDB4FAD0
treatment provided by	Plazi
scientific name	Polydrepanum spinatum Muhsina & Sudhikumar
status	sp. nov.

Treatment

Polydrepanum spinatum Muhsina & Sudhikumar sp. nov.

( Figs 5A View FIGURE 5 – 8D View FIGURE 8 )

Material examined. Holotype: 1 male ( CATE-MC, MS/154 ), India, Kakkad , Kozhikode , Kerala, 11.494722N, 75.960278E. 16 August 2024, evergreen forest, coll. Muhsina O. M. GoogleMaps Paratypes: 2 adult males, 5 females and 5 sub adults ( CATE-MC, MS/155 ), same date as for the holotype GoogleMaps .

Etymology: To emphasize many spines, present at the lateral margin of a curved solenomere; spina meaning “spine” in Latin. Adjective in neuter gender.

Diagnosis:Adult males of P. spinatum sp. nov. are distinguished from other members of the genus Polydrepanum based on the following combination of characters. Lacking adenostyles on male femora 1 and 2 ( Figs 7A and 7C View FIGURE 7 ). Other members of the genus possess an adenostyle on femur of the second leg only, except P. xiphosum sp. nov. having an adenostyle on the femora of first and second leg. Metazonites with six serrations on posterior margin (rings 2–19), pointing rearward ( Figs 5A–B, 5E View FIGURE 5 ). Not smooth like other members of the genus—except P. horridum with dense dorsal setae on metanoa/paranota. Gonopod: gonofemorite long, slender ( Figs 7D View FIGURE 7 and 8A–D View FIGURE 8 ); not stout as in P. tamilum . Short, circular distomesal process a. Laminar process b ( Figs 8A–D View FIGURE 8 ), not tapered like other Polydrepanum species. Solenophore with four spines on lateral margin ( Figs 8A–D View FIGURE 8 ); spines absent in P. tamilum , P. horridum , P. granuliferum , P. lamprum , P. xiphosum sp. nov.

Description: Length of holotype (male), 12.5 mm, of paratype (female), 12.3 mm; width of mid-body proand metazonites 1.1 and 1.2 mm, respectively. Width of paranota of midbody rings, 0.113 mm. Live specimens uniformly brownish-black. Paranota dark brown in both sexes. Legs latte brown. Coloration after preservation in 70% ethanol faded to brown; Paranota darker than body rings. Sternites and legs latte brown. ( Figs 5A–E View FIGURE 5 ). Body with 20 rings in both sexes ( Figs 5A–B View FIGURE 5 ). Relative ring widths: 20<19<4<3<18<2<1<5=16. Head and collum subequal in width; width of rings gradually reducing towards telson. Vertex smooth and shining, bearing two rows of setae. Stipes, cardo and clypeus moderately setose. Epicranial suture ending 0.1 mm above interantennal isthmus ( Fig. 5C View FIGURE 5 ). Antennae moderately long (1.9 mm), slightly claviform, extending until ring 5 when stretched dorsally. Relative lengths of antennomeres: 7<1<6<3<2<4<5.Antennomere 7 broadest apically. Postantennal groove shallow. Diameter of antennal socket and isthmus between them, 0.2 mm and 0.334 mm, respectively ( Fig. 5C View FIGURE 5 ). Collum broad, lateral margins poorly developed as paranota. Anterior margin of collum curved; posterior margin slightly concave. Paranota subtriangular. Collum dorsally bearing a row of setae at anterior margin and midline ( Fig. 5D View FIGURE 5 ). Anterior margin of body rings almost straight and bearing a row of moderately long and fragile setae ( Figs 5A–B, 5D–E View FIGURE 5 ). Moderately developed paranota, set high, lying parallel to body axis ( Figs 5E View FIGURE 5 and 6B View FIGURE 6 ). Posterior corner of collum paranota circular in shape; on rings 2 and 3, subtriangular in shape ( Fig. 5D View FIGURE 5 ); those of other body rings (4–19) pointed ( Figs 5E View FIGURE 5 and 6B View FIGURE 6 ). Posterior corner of paranota thickness towards telson ( Fig. 6B View FIGURE 6 ). Anterior margins of paranota on collum rounded. Paranota of ring 2 larger than that of other rings and set slightly lower than lateral margin of collum and paranota of following rings ( Fig. 6A View FIGURE 6 ). Lateral margin of paranota thicker on poriferous rings ( Figs 5E View FIGURE 5 and 6B View FIGURE 6 ). Pore formula normal (5, 7, 9, 10, 12, 13, 15–19); ozopores small, circular, opening posterolaterally at a thickened paranotal margin ( Figs 5E View FIGURE 5 and 6B View FIGURE 6 ). Posterior margin of rings 2–19 serrate, six serrations per ring, pointed towards posterior end of body ( Fig. 5D View FIGURE 5 ). Pleurosternal carinae decreasing in size from 2 to 4. Prozonites smooth. Metazonites smooth in anterior portion and medially. Shallow groove present near posterior edge on collum to ring 19. Posterior edge of rings 5–19 serrate; middle of posterior region not smooth, rough; strictures between pro- and metazonite deep and beaded or striolate at bottom ( Fig. 5E View FIGURE 5 ). Surface below paranota finely granulate ( Fig. 5F View FIGURE 5 ). Sterna with fine depressions, bare ( Fig. 5F View FIGURE 5 ). Legs short and slender, with tiny claws. Males with tarsal brushes. Coxa and prefemur bear a single long seta ( Fig. 7B View FIGURE 7 ). Relative length of podomeres: femur> prefemur> coxa> postfemur> tarsus> tibia. Male leg pairs 1 and 2 lacking adenostyle on femora ( Figs 7A and 7C View FIGURE 7 ). Gonopores visible in anterolateral region of male coxae 2 ( Fig. 7C View FIGURE 7 ). Pre-anal ring distinctly setose, with a pointed epiproct, flattened dorsomedially, overhanging both anal valves. Hypoproct semicircular in shape with 1+1 setae on small knobs at caudal margin ( Figs 6B–6D View FIGURE 6 ). Gonopodal aperture oval, about 2/3 as wide as prozonite 7. Gonopods long, complex, in situ lying close to sternites ( Fig. 7D View FIGURE 7 ). Gonopodal coxite cylindrical, shorter than femorite. Distal portion of coxite swollen and setose distolaterally; proximal part with a cannula, as usual ( Figs 8A–D View FIGURE 8 ). Prefemoral region short, densely setose ( Figs 8A–D View FIGURE 8 ). Gonofemorite long, slender and twisted: distomesally consisting of a laminar structure, process b; anterolaterally with a short and round structure representing process a. The seminal groove runs laterally at the base of the gonofemorite, then turns medially at the distal one-third of the gonofemorite. A long and circular solenomere attached to solenophore. Four spines at lateral margin of solenomere ( Figs 8A–8D View FIGURE 8 ).