Parastenonia parae ( Cook, 1895 )

Bouzan, Rodrigo S., Iniesta, Luiz Felipe M., de Souza, Claudio A. R., Zampaulo, Robson A. & Brescovit, Antonio D., 2020, Taxonomic review of the Amazonian millipede genus Parastenonia Hoffman, 1977 and description of a new species from iron-ore caves (Polydesmida: Chelodesmidae), Journal of Natural History 53 (45 - 46), pp. 2781-2799 : 2784-2790

Parastenonia parae ( Cook, 1895)

( Figures 1 (a), 5, 6, and 11(a,b))

Priodesmus parae Cook, 1895: 56 (Female holotype labelled only ‘ Para ’, Brazil, deposited in ZMB, examined by photographs). Attems 1899: 429; 1938: 64. Brölemann 1909: 81.

Parastenonia parae: Hoffman, 1977: 354 .

Priodesmus aurae Schubart, 1947: 45 , figs 44−45 (male syntype [ MNRJ 11825 ] and four females syntypes [MZUSP 1082; MZUSP 1083; MNRJ 11823 ; MNRJ 11824 ] from Aurá , Ananindeua (48°30 ʹ 15 ” W, 01°27 ʹ 21 ” S), Pará, Brazil, 16/IV−2/VI/1940, A.L. Carvalho coll., examined). New synonymy.

Parastenonia aurae: Hoffman, 1977: 354 .

Synonymy

Cook (1895) described P. parae from a single specimen from the state of Pará, but without a specific location. Attems (1938, p. 64) considered the species as incertae sedis, and Jeekel (1963, p. 101) mentioned as its possible synonym Parastenonia aurae , due to a presumed overlapping distribution and a concordant description of both species an opinion also expressed by Hoffman (1977b, p. 354).

Based on the examination of the type specimens of both nominal species, the identical shape of the cyphopods ( Figures 5 (b,c) and 6(c – f)) suggests indeed their synonymy. In addition, presumably the exact type locality of the material gathered by Cook corresponds to the coastal area of the state of Pará (the same for P. aurae ), mainly due to the easy access and by a long history of naturalist expeditions ( Schubart 1947) . Therefore, P. aurae is proposed herein as a junior synonym of P. parae .

Diagnosis

Adult males of Parastenonia parae differ from those of P. carajas sp. nov. based on the combination of gonopodal characteristics: apical portion of the solenomere broad ( Figure 6 (a,b)); presence of a secondary denticulated process on the prefemoral process of the gonopod ( Figure 6 (b)). Adult females of Parastenonia parae differ from those of P. carajas sp. nov. based on a combination of cyphopodal characteristics: valves of the cyphopod asymmetric and absence of an upper projection ( Figure 6 (c – f)).

Redescription

Measurements: (MNRJ 11825). Total length: unknown (body very fragmented and with parts missing). Width (body ring 5): 3.02.

Female (MZUSP 1082). Total length: 32.30. Width (body ring 5): 3.19. Telson 0.842.

Colouration (in alcohol 70%). Head missing. Body ochre and paranota tip with the same colour as the body. Legs whitish yellow. Telson missing. Female colouration reddish brown. Body as in male ( Figure 1 (a)).

Body rings. Fragmented and many parts of body missing. Integument with small tubercles and with a transversal groove on the metazonite; alignment of paranota straight; paranota divided laterally into three lobes: pro with usually three large processes; meso with two large processes except when the ozopore is present; meta usually with two processes. Sternite without modifications.

Male sexual characters

Gonopods. Gonopods ( Figure 6 (a,b)): gonopod coxae (Cx) dorsally elevated, equivalent to more than half the length of the telopodite and prominent in ectal view. Coxae with several setae in the distal dorsal side and several small bristles on the ventral side. Without a coxal apophysis. Prefemoral region long. Prefemoral process (PfP) wide, narrow in the final portion, branched at the base, with a shorter secondary process with the edge denticulated ( Figure 6 (b)). Femoral region branched at the base. Acropodite process slender and acuminate. The solenomere is the largest process carrying the seminal groove that extends until the apical part; elongated and broad. Gonopore and gonopod aperture on seventh body ring missing.

Female sexual characters

Cyphopods. Posterior edge of the cyphopod aperture with a medium rounded projection. Cyphopods ( Figure 6 (c – f)) with thick setae dispersed on the valves. Apical part of

cyphopod concave ( Figure 6 (c)), with the intermediate membrane projecting between the valves ( Figure 6 (e – f)).

Distribution

Known only from Aurá, Ananindeua, state of Pará, Brazil ( Figure 11 (a)).

Figures

Figure 1. Habitus images: (a) Parastenonia parae female (MZUSP 1082); (b) P. carajas sp. nov. (IBSP 4914). Scale bars: (a) 2,5 mm; (b) 2 mm.

Figure 5. Parastenonia parae female holotype (ZMB): (a) Midbody rings in detail; (b) Aperture of the cyphopods. Arrow indicates the cyphopod; (c) Cyphopods in ventral view.

Figure 6. Parastenonia parae male (MNRJ 11825) and female (MZUSP 1082), microscope and stereoscope images of the gonopod and cyphopods: (a) Gonopod in mesal view; (b) Distal portion of the gonopod; (c) Cyphopod in ectal view;(d) Detail of the junction between the internal and external valva; (e) Cyphopod in posterior view;(f) Cyphopod in anterior view.Scale bars: (a) 500 µm;(b) 250 µm;(c) 500 µm;(d) 250 µm; (e) 500 µm; (f) 500 µm.

Figure 11. Distribution map of Parastenonia parae and P. carajas sp. nov.: (a) South America; (b) Northern of Brazil. Pará state highlighted in grey; (c) Iron-ore outcrop in the Pará state; (d) Satellite image of the iron-ore outcrop where the caves were sampled.