Pseudonannolene leucomelas * Schubart 1947

Pseudonannolene leucomelas Schubart, 1947

Figs 12, 81– 82, 165N, 184

Pseudonannolene leucomelas Schubart, 1947: 32, figs 32–34.

Pseudonannolene leucomelas – Schubart 1958: 240. — Jeekel 2004: 89. — Golovatch et al. 2005: 279. — Gallo & Bichuette 2020: 36.

Diagnosis

Adults resemble those of P. spelaea by the reduced number of ommatidia (less than 15 ommatidia) (Fig. 81A), but differing by having solenomere with evident and elongated seminal apophysis; internal branch with long setae restricted to the apical margin (Fig. 82D).

Etymology

Name ‘leucomelas’ taken from the Greek words ‘ lefkó ’ = ‘white’, plus ‘ mélās ’ = ‘black’, referring to the pattern of coloration of the body rings of the species (Schubart 1947).

Material examined

Holotype BRAZIL • ♂ [fragmented in two different vials and in microscope slide; gonopod, first and second leg-pair missing]; Mato Grosso, Barra do Tapirapé [= Santa Terezinha]; [-10.501639, -50.731877]; Dec. 1939; A.L. Carvalho leg.; MNRJ 11828 [some body rings], MNRJ 11826 [head and remaining body rings], MZSP [body ring on microscope slide].

Paratypes (total: 3 ♀♀, 2 immatures) BRAZIL • 1 ♀; same collection data as for holotype; MZSP • 2 ♀♀, 2 immatures; same collection data as for holotype; MNRJ 11829.

Descriptive notes

Gonopod description adapted from Schubart (1947: 32) to supplement original description and to introduce gonopod terminology; remaining male sexual characters described based on examined syntype and non-sexual characters described only for female.

MEASUREMENTS. 62–65 body rings (2–3 apodous + telson). Males: fragmented, body length ca 25 mm; maximum midbody diameter 1.5 mm. Females: fragmented, body length 27–30 mm; maximum midbody diameter 1.6 mm.

COLOR. Body color faded, but apparently prozonites dark brown, metazonites with a lighter posterior band; head, collum, antennae, and legs dark brownish.

HEAD. Antennae short (Fig. 81A), just reaching back to end of ring 5 when extended dorsally; relative antennomere lengths 1<2<3>4<5≈6>7. Mandibular cardo with ventral margin narrow. Ommatidial cluster reduced and almost entirely covered by collum; ca 15 ommatidia in 3 rows.

BODY RINGS. Collum with lateral lobes broadly subrectangular, with ca 5 thickened striae, slightly curved mesad (Fig. 81A). Very faintly constricted between prozonite and metazonite; prozonites smooth; metazonites laterally with transverse striae below ozopore. Anterior sterna in midbody rings subrectangular, without transverse striae (Fig. 82C).

FIRST LEG-PAIR OF MALES. Coxae (cx) short (less than half of remaining podomere lengths), subtriangular, with the base arched, densely setose; prefemoral process (prf) as wide as half of prefemur, subcylindrical, densely setose up to its median region; remaining podomeres with setae along the mesal region.

SECOND LEG-PAIR OF MALES. Coxa (cx) large and rounded; penis (pn) located at proximal region, rounded, not extended basally; prefemur compressed dorsoventrally; remaining podomeres setose.

GONOPODS. Gonocoxa (gcx) elongated, medially expanded and thinning towards apex; slightly flattened antero-posteriorly; with rows of papillae mesally. Seminal groove (sg) protruded on squamous region of sl, terminating apically on the seminal apophysis (sa). Shoulder absent. Telopodite (tp) less wide than half of gcx; solenomere (sl) with sa thickened, visible apically; ectal process absent; sa located at medial portion, visible apically. Internal branch (ib) shovel-shaped, with horizontal plate; setae restricted to the apical region of ib exceeding seminal region of sl (Fig. 82D).

VULVAE. As typical for the genus. Bursa subtriangular, glabrous; internal valve subtriangular; operculum narrow, curved medially; external valve wide, subtriangular.

Distribution

Known only from the type locality Santa Terezinha (formerly Barra do Tapirapé), Mato Grosso, Brazil (Fig. 184). The indigenous region of “Barra do Tapirapé” is restricted to the marginal forests in the Araguaia River, with typical Amazonian fauna and flora interspersed by patches of Cerrado (tropical savannah).