Pseudonannolene pusilla Silvestri, 1895

Iniesta, Luiz Felipe Moretti, Bouzan, Rodrigo Salvador & Brescovit, Antonio Domingos, 2023, A reassessment of the Neotropical genus Pseudonannolene Silvestri, 1895: cladistic analysis, biogeography, and taxonomic review (Spirostreptida: Pseudonannolenidae), European Journal of Taxonomy 867 (1), pp. 1-312 : 71-73

Pseudonannolene pusilla Silvestri, 1895

Figs 111–112 , 176A , 178H , 186

Pseudonannolene pusilla Silvestri, 1895b: 7 , fig. 13.

Pseudonannolene pusilla – Silvestri 1902: 23. — Schubart 1958: 240. — Viggiani 1973: 367. — Jeekel 2004: 90. — Golovatch et al. 2005: 279. — Iniesta & Ferreira 2013a: 92; 2013c: 79.

Diagnosis

Males of P. pusilla resemble those of P. morettii sp. nov. by having short coxae on the first leg-pair with a constriction at about midlength ( Fig. 112A ), but differing by the absence of long scattered setae on the mentum and stipes ( Fig. 176A ); solenomere short and subtriangular ( Fig. 112D ).

Etymology

Named after the Latin adjective ‘ pusillus ’ (feminine ‘ pusilla ’) = ‘very little’, ‘tiny’. Unspecified in the original description.

Material examined (total: 5 ♂♂, 2 ♀♀, 3 immatures)

BRAZIL – Mato Grosso • 2 ♂♂; Pindaíba , Barra das Garças; [-15.881182, -52.238738]; 337 m a.s.l.; 19–31 Jan. 1998; M.E.V. Callefo leg.; IBSP 13390 • 3 ♂♂, 2 ♀♀, 3 immatures; same collection data as for preceding; IBSP 13391 .

Descriptive notes

MEASUREMENTS. 55–57 body rings (1 apodous + telson). Males: body length 39.7 mm; maximum midbody diameter 2.4 mm. Females: body length 43.1–44 mm; maximum midbody diameter 3.7–4 mm.

COLOR. Body color brownish grey; head and collum darker; prozonites anteriorly greyish; metazonites with a posterior band lighter; antennae and legs brownish.

HEAD. Antennae long ( Fig. 111A ), just reaching back to end of ring 6 when extended dorsally; antennomeres elongated; relative antennomere lengths 1<2<3>4=5≈6>7. Mandibular cardo with ventral margin narrow. Ommatidial cluster well-developed, elliptical; ca 40 ommatidia in 5 rows.

BODY RINGS. Collum with lateral lobes rounded, with ca 12 striae, strongly curved ectad ( Fig. 111A ). Very faintly constricted between prozonite and metazonite; prozonites smooth; metazonites laterally with transverse striae above ozopore in anterior body rings. Anterior sterna in midbody rings subrectangular, without transverse striae ( Fig. 176A ).

FIRST LEG-PAIR OF MALES. Coxae (cx) short (less than half of remaining podomere lengths), subtriangular, with the base strongly arched and constricted medially, sparsely setose ( Fig. 112A ); prefemoral process (prf) less than half of prefemur, subcylindrical, densely setose up to its median region ( Fig. 112B ); remaining podomeres with setae along the mesal region.

SECOND LEG-PAIR OF MALES. Coxa (cx) rounded; penis (pn) located at proximal region, rounded, not extended basally ( Fig. 112C ); prefemur compressed dorsoventrally; remaining podomeres setose.

GONOPODS. Gonocoxa (gcx) elongated, twice longer than telopodite, with the base arched; antero-posteriorly flattened ( Fig. 112D–F ); with rows of papillae mesally. Seminal groove (sg) curved; arising medially on mesal cavity and terminating apically on the seminal apophysis (sa). Shoulder (sh) inconspicuous. Telopodite (tp) almost as wide as gcx ( Fig. 112D ); solenomere (sl) with small squamous region; apicomesal process (amp) subtriangular; ectal process absent; sa located at mesal portion, slightly visible apically in oral view ( Fig. 112F ). Internal branch (ib) subtriangular, narrow and foliaceous, surrounding basally tp as a shield; ib with setae along its entire margin nearly not exceeding apically seminal region of sl ( Fig. 112D–F ).

VULVAE. As typical for the genus. Bursa subtriangular, glabrous ( Fig. 178H ); internal valve subtriangular, with its sides having the same length; operculum slightly curved ectad; external valve large, subtriangular.

Distribution

Known from Cerrado biome in the west region of Mato Grosso State, Brazil; other records from the literature for the Brazilian states of Mato Grosso do Sul and Goiás, and region of the Chaco in Argentina and Paraguay ( Fig. 186 ).

Comments

The type material was described by Silvestri (1895b) and supposedly deposited at the Museo Regionale Scienze Naturali, Torino, Italy (MRSN) ( Viggiani 1973: 367), but was not found. Nevertheless, neartopotypes from Mato Grosso were examined ( Fig. 186 ). Other specimens from Brazil (Goiás, Mato Grosso, and Mato Grosso do Sul) and Paraguay (Asunción) were recorded by Silvestri (1902).

Figures

Fig. 111. Pseudonannolene pusilla Silvestri, 1895, ♂ (IBSP 13390), in lateral view. A. Anterior region. B. Posterior region. Scale bars = 0.5 mm.

Fig. 112. Pseudonannolene pusilla Silvestri, 1895, ♂ (IBSP 13390). A. First leg-pair. B. Detail of prefemur. C. Second leg-pair. D. Detail of telopodites, in anal view. E. Gonopods, in anal view. F. Gonopods, in oral view. Abbreviations: see Material and methods. Scale bars: A, C, E–F = 0.5 mm; B, D = 0.2 mm.

Fig. 176. Stereoscopic images of gnathochilarium and anterior sternum of species of Pseudonannolene Silvestri, 1895. A. P. pusilla Silvestri, 1895. B. P. bovei Silvestri, 1895. C. P. brevis Silvestri, 1902. D. P. centralis Silvestri, 1902. E. P. rugosetta Silvestri, 1897. F. P. sulcatula Silvestri, 1895. Images not to scale.

Fig. 178. Stereoscopic images of left vulva of species of Pseudonannolene Silvestri, 1895, in oral view. A. P. magna Udulutsch & Pietrobon, 2003. B. P. maritima Schubart, 1949. C. P. mesai Fontanetti, 2000. D. P. microzoporus Mauriès, 1987. E. P. occidentalis Schubart, 1958. F. P. ophiiulus Schubart, 1944. G. P. parvula Silvestri, 1902. H. P. pusilla Silvestri, 1895. I. P. paulista Brölemann, 1902. J. P. robsoni Iniesta & Ferreira, 2014. K. P. rolamossa Iniesta & Ferreira, 2013. L. P. sebastianus Brölemann, 1902. M. P. segmentata Silvestri, 1895. N. P. silvestris Schubart, 1944. O. P. spelaea Iniesta & Ferreira, 2013. Images not to scale.

Fig. 186. Distribution map of the species Pseudonannolene parvula Silvestri, 1902, P. patagonica Brölemann, 1902, P. paulista Brölemann, 1902, P. pusilla Silvestri, 1895, and P. robsoni Iniesta & Ferreira, 2014.