Pseudonannolene saguassu Iniesta & Ferreira, 2013

Iniesta, Luiz Felipe Moretti & Ferreira, Rodrigo Lopes, 2013, Two new species of Pseudonannolene Silvestri, 1895 from Brazilian limestone caves (Spirostreptida: Pseudonannolenidae): synotopy of a troglophilic and a troglobiotic species, Zootaxa 3702 (4), pp. 357-369 : 363-364

Pseudonannolene saguassu Iniesta & Ferreira, 2013 .

( Figs. 7–10 )

Material examined: Holotype: 1 Male (Fragmented, ISLA 2266), from Gruta do Éden, Pains/MG, Brazil, 15/III/ 2012.

Etimology. Saguassu (saguaçú) comes from the Tupi-Grarani origin (Brazilian Indian languages), meaning “those with big eyes”. This name obviously refers to the numerous ocelli observed in this species. It is to be treated as a noun in apposition.

Diagnosis. Body with 69 rings and brownish coloration. About 45 Ocelli, pigmented. 30 labral setae and mandible with 11 pectinate lamellae. Gonopod with rhomboid solonomere and a central spine. Basal section 0.75 times longer than wide and distal section about 0.5 times longer than wide.

Measurements: Length of 65.16 mm; maximum midbody diameter of 3.68 mm; 69 body rings; length of antennae of 3.67 mm (relation to diameter 0.99); length of legs 2.60 mm (relation to diameter 0.71); length of tarsal claw 0.2 mm (relation to diameter 0.05).

Color: Brownish.

Description of adults. Head ( Fig. 7 ): Head glabrous and pigmented. Three small labral teeth, a row of 30 labral setae and above a row of 6 supra labral setae (one apparently missing). Mandibles pigmented, glabrous and with 2 external teeth above, 5 internal teeth and 11 pectinate lamellae. Eyes pigmented with 45 ocelli, distributed into 5–6 rows. Antennae pigmented and densely setose. First antennomere small, second and third antennomeres of similar sizes, fourth and fifth antennomeres shorter than third. Sixth antennomere longer and wider than the fourth and fifth. Groups of basiconic sensilla on the edge of the fifth and sixth antennomeres. Four terminal sensory cones.

Gnathochilarium ( Fig. 8 A; B): Gula (Gu) with short setae. Mentum (Me) rounded and with base wider than the latter. Stipes (St) with base shorter than distal region. Promentum (Pme) with two trianguliform parts and Laminae linguales (Ll) entirely separated by Pme.

Trunk: Body with 69 rings. Tergites and collum pigmented (homogeneously brownish). Lateral transverse striae present (striae variables into individuals). Anal shield and anal valve pigmented like the trunk.

First male pair of legs ( Fig. 9 A): The first leg pair is modified and densely setose. Coxae (Cx) with basis longer than distal region. Distal region with a shoulder. Sternum not visible. Prefemur (Prf) with thin oral process parallel (P) to the coxa, more rounded in distal ( Fig. 9 B). Post-femur (Psf) and tíbia (Tb) reduced. Femur (F) elongated. Terminal claw (Tc) not modified.

Gonopod ( Fig. 10 A; B): Gonopod short and stout. Coxae (Cx) little visible and glabrous. The basal section (Bs) of telopodite glabrous, 0.75 times longer than wide. Shoulder absent. Basiconic sensilla (B) extending along the membranous margin from basal section. Distal section (Ds) about 0.5 times longer than width and with two well-developed processes, the solenomere (S) and an internal (seminal) branch (Ib). S rhomboid and with a squamous surface coating the structure. Spine (Sp) present in center of the apex. Ib (coxosternal branch?) digitiform and supporting setae at distal region that exceeds the length of S. Short seminal groove (Sg) between S and Ib.

Remarks. Morphological analysis was performed by stereoscopic observations and light microscopy in a single male specimen. The specimen was found in an area between the twilight and aphotic zones of Gruta do Éden, near the vertical entrance ( Fig. 1 B). In the same cave, there is a huge population of P. ambuatinga , which is distributed especially in the main conduit of the cave, however, cut by a stream. Accordingly, this cave represents the first case of syntopic species of Pseudonannolene occurring in Brazilian caves. However, it is very likely that P. saguassu actually represents an “accidental” species, since only a single specimen was found during many visits paid to the cave. Since the external (epigean) environment was not properly sampled, it is plausible to assume that the main habitat of this species is the external semi-deciduous forest which covers the area. Therefore, it is not possible to consider the species as “rare” based on the fact that only a single specimen was collected.

Figures

FIGURE 1. Distribution map of P. ambuatinga n. sp. and P. saguassu n. sp. A) Map of Brazil and Minas Gerais state, indicating the location of the Pains municipality; B) Map of the Gruta do Éden. The arrows show the cave entrances (blue arrow—natural entrance; red arrow—artificial entrance, opened by mining activities). The blue star indicates the area where P. saguassu was found and the yellow area shows the population distribution of P. ambuatinga inside the cave; C) Artificial entrance of the Gruta do Éden (red arrow); D) Upper conduits of the cave; E) Stream conduit, in which the population of P. ambuatinga lives; F) P. ambuatinga n. sp. found walking under the water; G) P. ambuatinga n. sp. on a rock.

FIGURE 7. P. saguassu n. sp., holotype male (ISLA 2266), stereoscope images. Detail of anterior region;

FIGURE 8. P. saguassu n. sp., holotype male (ISLA 2266), micrographic images. A) gnatochilarium; B) Detail of the gnatochilarium. Abbreviations: Gu = gula; St = stipes; Me = mentum; Pme = pro-mentum; Ll = Laminae linguaies; Op = outer palpus; Ip = inner palpus. Scales bars: A = 100 µm; B = 20 µm.

FIGURE 9. P. saguassu n. sp., holotype male (ISLA 2266), stereoscope images. A) First pair of legs; B) Details of the oral process. Abbreviations: Cx = coxae; P = process; Pf = pre-femur; F = femur.

FIGURE 10. P. saguassu n. sp., holotype male (ISLA 2266), stereoscope images and schematic drawings. A) Gonopod; B) Schematic drawing of the gonopod. Abbreviations: Bs = basal segment; Ds = distal segment; B = basiconic bistles; Ib = internal branch; S = solenomere; Sp = spine; Sg = seminal groove. Scale bars: 500 µm.