Taxonomic review of the Amazonian millipede genus Parastenonia Hoffman, 1977 and description of a new species from iron-ore caves (Polydesmida: Chelodesmidae) Author Bouzan, Rodrigo S. Author Iniesta, Luiz Felipe M. Author de Souza, Claudio A. R. Author Zampaulo, Robson A. Author Brescovit, Antonio D. text Journal of Natural History 2020 2020-04-28 53 45 - 46 2781 2799 http://dx.doi.org/10.1080/00222933.2020.1749956 journal article 10.1080/00222933.2020.1749956 1464-5262 4608825 CCBEED10-DCB4-48C9-A71D-CED3462DD72A Family CHELODESMIDAE Cook, 1895 Subfamily CHELODESMINAE Cook, 1895 Tribe Priodesmini Hoffman, 1977 Genus Parastenonia Hoffman, 1977 Parastenonia Hoffman, 1977: 449 459 . Type species: Priodesmus aurae Schubart, 1947 [= Priodesmus parae Cook 1895 ], by original designation. Hoffman 1980: 152 ; Shelley et al. 2000: 120 . Diagnosis Males of Parastenonia differ from those of other chelodesmid genera by the combination of the following characters: metaterga granular and crossed by a transversal sulcus ( Figure 4 (d)), as in Cypraeogona , Cayenniola , Cearodesmus and Brasiloschubartia , from which however this genus differs in the shape of the gonopod; lateral edge of paranota trilobed by the presence of two deep sinuses ( Figure 4 (a,b)), as in Priodesmus and Stenonia , (see Attems 1938 , figs 68 69; Jeekel 1963 , figs 30 32) however without modifications on the walking legs; gonocoxae large, with a dorsal field of setae; a long slender acuminate process on acropodite and an elongated prefemoral process ( Figure 9 (a,b)). Redescription General measurements. Body length between 32.30 mm (female of P. parae ) and 22.60 mm (male of P. carajas sp. nov. ). Colouration (in 70% ethanol). Variable among species, ranging from reddish brown to ochre. Head. With scattered tubercles, some of which bearing setae ( Figure 2 (a f)); shape of the incisura lateralis suboval. Antenna elongated, about 1.5x the width of midbody ring ( Figure 3 (a d)). Body rings. Integument with small tubercles, without setae ( Figure 4 (a,b,d,e)). A transversal groove on the metazonite. Collum with the anterior border arched and posterior border straight. Spiracles oval. Sternites without modifications. Ozopores on trunk rings: 5, 7, 9, 10, 12, 13, 15 19 (the standard polydesmid pore formula), located at the tip of the intermediate paranotum; and surrounded by peritremata. Paranota: prominent and long, wide, covering part of the legs, without setae on the edges. Paranota divided laterally into three lobes: -pro; -meso and -meta ( Figure 4 (a,b)). Telson: triangular, wide and with tubercles ( Figure 4 (e)). Epiproct with five pairs of macrosetae projecting through the tubercles on the dorsal side and two pairs in the apical region; paraproct with two macrosetae on each valve; hypoproct with two macrosetae. Legs. Granulated; scattered setae along the entire surface ( Figure 4 (c)). Male sexual characters. Gonopore located on the coxae of the legs of the third body ring, coxae rounded, with a large apical pore ( Figure 9 (a)). Gonopod aperture large, rectangular-shaped; posterior edge slightly folded ( Figures 8 (a b) and 9(b)). Gonopods: coxae ( Cx ; Figures 6 (a) and 9(c,d)) equivalent to about half the length of the telopodite, without spiniform process, with several setae on dorsal side; coxae dorsally prominent in ectal view. Cannula ( C ; Figure 9 (e)) robust and hook-shaped. Spermatic groove: runs along the mesal side of the acropodite in the entire length ( SG ; Figure 6 (b)). Telopodite elongated, divided into two parts: the prefemoral region ( Figure 9 (d)) and the femoral region ( Figure 9 (d)). Prefemoral process ( Figure 9 (d)): branch long with stretch marks ( Figure 9 (f)). Acropodite long divided into two parts, the larger central branch is the solenomere carrying the spermatic groove with a thin elongated branch, rising proximally from the femoral region ( Figure 9 (d)). Female sexual characters. Cyphopods elongated, situated directly behind the second pair of legs on the third body ring; composed of valves and operculum, all densely setose; two valves joined by a membrane and operculum apically, appressed against both larger valves ( Figures 6 (c f) and 10(a e)). A small projection of the valves with S-shaped curvature in the intermediate membrane ( Figures 6 (c,d) and 10(a)). Included species Two species: Parastenonia parae ( Cook, 1895 ) and P. carajas sp. nov. Distribution Known only from Amazon rainforest in the state of Pará, Brazil ( Figure 11 ).