Otostigmus (Parotostigmus) beckeri, Chagas-Júnior, Amazonas, 2012

Chagas-Júnior, Amazonas, 2012, The centipede genus Otostigmus Porat in Brazil: Description of three new species from the Atlantic Forest; a summary and an identification key to the Brazilian species of this genus (Chilopoda, Scolopendromorpha, Scolopendridae, Otostigminae), Zootaxa 3280, pp. 1-28 : 2-5

Otostigmus (Parotostigmus) beckeri sp. n.

Figures 1–10

Type-specimens. Holotype, male (MNRJ 16019) and 3 paratypes, 1 female (MNRJ 16014) and 2 males (IBSP 3633 and MZSP), all from Reserva Biológica de Una, Una collected in 08–10.vi.2009 by A. Chagas, A. Kury, D. Pedroso, A. Giupponi & V. Dill. Another male paratype (MNRJ 15374) from Reserva Particular do Patrimônio Natural da Serra Bonita, Camacan collected in 14.iii.2008 by V. Dill. Both localities are in the state of Bahia, Brazil.

Additional material. 1 male and 1 female ( MNRJ 15232) from Condomínio Alphaville, Salvador, state of Bahia collected in 11.x.2001 by G. Montingelli.

Etymology. The specific epithet honors Dr. Vitor O. Becker, an entomologist, responsible for the administration of the Reserva Particular do Patrimônio Natural da Serra Bonita, Camacan.

Diagnosis. Cephalic plate smooth, without sutures, but with two slightly short longitudinal depressions at the posterior border; tooth plates slightly wider than long. First eleven tergites in male and eight tergites in female smooth, from tergite 12 in male and tergite 17 in female to tergite 21 with small blunt spinules or tubercles increasing gradually towards the posterior end; tergites 1 to 4 without sutures; tergites 5 to 20 with complete paramedian sutures and tergites 3 to 20 with a low median longitudinal incomplete keel; tergites 8 to 20 marginate; tergite 21 with incomplete median longitudinal keel and shallow longitudinal depression on each side of this keel; central part of the posterior border slightly convex and with a shallow depression. Sternites 2 to 20 with a rounded depression in the center, sternites 2 to 19 with three small weak rounded depressions arranged transversally at the posterior border. Coxopleuron with numerous pores; apical border not prominent, truncate and without spines. Legs 2 to 20 with one tarsal spur, leg 21 without. Prefemur of the ultimate pair of legs without spines, but males have a digitiform appendix as long as the prefemur, this appendix is slightly flattened dorsoventrally in the proximal half and concave in the distal half; with a tuft of reddish hairs in the dorsal side. Prefemur of ultimate legs of females without spines or digitiform appendix.

Description. Holotype (male) and paratype (female)

Length: 46 mm from the anterior border of the cephalic plate to the posterior border of tergite 21 and ultimate pair of legs 13 mm long (holotype). 52 mm from the anterior border of the cephalic plate to the posterior border of 21st tergite and ultimate pair of legs 11 mm long (paratype).

Color: cephalic plate, tergites 1 to 20 and coxosternite dark greenish blue; area under ocelli light brown. Leg bearing segment 21, penultimate and ultimate pairs of legs violet. Antennae light violet; from the ¾ of article III to article XVII covered by yellowish hairs. Sternites and legs 1 to 19 light blue. Margin of coxosternal tooth plates, tarsungula, trochanteroprefemur, spiracles, tibial and tarsal spurs, and distal parts of pretarsi red-brown.

Cephalic plate smooth, without sutures or sulci, but with two slight short longitudinal depressions at the posterior border ( Figure 1 ). These depressions are almost covered by the anterior border of tergite 1.

Antennae: reaching the anterior border of tergite 5; with seventeen articles; first two articles and ¼ of the third glabrous; from the apical quarter of article III densely hirsute, with short yellowish hairs.

The article 2 of telepodite of the second maxillae without spur.

Forcipular coxosternum with slightly rounded depression below tooth plates (Figure 2); tooth plates slightly wider than long, with 4 teeth in each plate (Figure 4); a long bristle in the center of each plate; beneath the tooth plate there is a short median longitudinal sulcus and a transversal obtuse sulcus bordering the bases of tooth plates (Figures 2 and 4). Process of forcipular trochanteroprefemur with two low inner teeth and terminating in an acute tip (Figure 4).

First eleven tergites in male and eight tergites in female smooth, but from tergite 12 in male and tergite 17 in female to tergite 21 with small blunt spinules or tubercles increasing gradually towards the posterior end; lateral sides of tergites 4 to 20 with weak corrugations. Tergites 1 to 4 without sutures ( Figure 3); tergites 5 to 20 with complete paramedian sutures, tergites 3 to 20 with a low incomplete median longitudinal keel ( Figure 5); tergites 8 to 21 marginate; tergite 21 with incomplete median longitudinal keel and low longitudinal depression on each side of this keel ( Figure 7); central part of the posterior border slightly convex and with a low depression ( Figure 7). In the female, tergites 1 to 4 without sutures; tergites 5 to 6 with short incomplete paramedian sutures at the posterior border, tergites 8 to 20 with complete paramedian sutures. Tergite 7 to 21 marginate. Tergite 21 without keel and the central part of the posterior border slightly convex and with a low depression.

Sternites smooth, with anterior margin wider than posterior ( Figure 6); sternites 2 to 20 with a rounded depression in the center, sternites 2 to 19 with three small weak rounded depressions arranged transversally at the posterior border ( Figure 6); sternite 21 longer than wide, converging posteriorly and with a slight median longitudinal depression; posterior border straight ( Figure 8).

Coxopleuron with numerous pores; pore field almost covering the whole coxopleuron, only the posterior and dorsal part without pores; apical border not prominent, truncate and without spines ( Figures 8 and 9 ).

Legs smooth; leg 1 with femur and tibia with one and tarsus with two spurs; legs 2 to 20 with one tarsal spur, leg 21 without. Pretarsus of legs 1 to 21 with anterior and posterior accessory spurs.

Prefemur of the ultimate pair of legs without spines, but males have a digitiform appendix as long as the prefemur ( Figures 7 and 10). This appendix is attached to the base of the dorsomedial side of prefemur. Digitiform appendix slightly flattened dorsoventrally in its proximal half ( Figure 10); the distal half with a shallow longitudinal depression deepening distally, the tip curved dorsally ( Figure 9 ), and a tuft of reddish hairs on the dorsal side ( Figure 10). Prefemur of ultimate legs of females without spines and digitiform appendix.

Type locality. Reserva Biológica de Una, Una, state of Bahia.

Distribution. Atlantic Forest of state of Bahia.

Remarks. O. beckeri resembles O. scabricauda ( Humbert & Saussure, 1870) , O. rex Chamberlin, 1914 , O. diringshofeni Bücherl, 1969 and O. demelloi Verhoeff, 1937 in the presence of a digitiform appendix on the prefemur of the ultimate pair of legs in males, but the shape of the appendix and the position of the tuft of hairs are different. In O. scabricauda and O. demelloi the appendix is rounded, in O. diringshofeni and O. rex the dorsal side is slightly flattened dorsoventrally. In O. scabricauda the tuft emerges from a terminal concavity, in O. demelloi the tip of the appendix is oblique and accommodates the tuft of hairs ( Verhoeff, 1937) and in O. diringshofeni and O. rex the tuft of hairs is borne terminally on the dorsal side.

Figures

FIGURE 1. Otostigmus beckeri n. sp., male holotype (MNRJ 16019). Cephalic plate and tergites 1 and 2.. Scale bar 1 mm. FIGURE 2. Otostigmus beckeri n. sp., male holotype (MNRJ 16019). Forcipular coxosternum. Scale bar 1 mm. [forcipular and first leg-bearing segments]

FIGURE 9. Otostigmus beckeri n. sp., male holotype (MNRJ 16019). Leg-bearing segment 21, coxopleuron and digitiform appendix. Lateral view. Scale bar 1 mm.