Otostigmus (Parotostigmus) rex Chamberlin, 1914

Chagas-Jr, Amazonas, 2016, A systematic appraisal of the types of ten species of Otostigmus (Parotostigmus) (Scolopendromorpha, Scolopendridae, Otostigminae), Zootaxa 4147 (1), pp. 36-58 : 46-47

Otostigmus (Parotostigmus) rex Chamberlin, 1914

( Figures 20–21 )

Otostigmus rex Chamberlin, 1914: 176 ; Bücherl, 1940: 222; Otostigmus (Androstigmus) rex Bücherl, 1942: 59 ;

Otostigmus (Parotostigmus) rex Bücherl, 1974: 115 .

Type material examined. Holotype MCZ IZ no.1476 (14535), Brazil, Mato Grosso, Madeira-Mamore, Railroad Camp 39, Stanford Expedition to Brazil 1911, Coll: W.M. Mann, 1911 ( Figs 20–21 ).

Redescription (female). Length: 78 mm from the anterior margin of the cephalic plate to the posterior margin of tergite 21. Right antenna with 17 articles and left with 14 (damaged); two basal articles glabrous. Cephalic plate smooth, without sutures and depressions (punctate, very fine and rather weak).

Coxosternal tooth-plates wider than long with 4+4 teeth, a strong seta on each plate. Coxosternite with a short median longitudinal suture and transverse suture at the base of the tooth-plates, the latter laterally bifurcate. Forcipular trochanteroprefemoral process larger than the tooth plates and distally pointed.

The tooth-plates and the lateral margin of the trochanteroprefemoral process worn.

Tergites 5–20 with complete paramedian sutures; tergites 6–21 marginate; tergites 6–20 with a shallow median longitudinal keel; tergites 9–20 laterally rugose; tergites 16–21 with many tubercles; tergite 21 with a shallow and deep depression at posterior margin; posterior margin lightly convex.

Sternites without sutures, but with depressions from sternites 3–19; sternite 21 with a median longitudinal depression and straight posterior margin.

Coxopleuron without spines and with pore-field covers almost the entire coxopleuron; posterior end of the coxopleuron poreless; terminal part of coxopleura rounded.

Legs 2–19 with one tarsal spur, lacking legs 1.

Remarks. O. rex was the fourth of five species of Otostigmus (Parotostigmus) described by Chamberlin (1914). Otostigmus amazonae Chamberlin, 1914 and O. tidius Chamberlin, 1914 were described from Manaus, and O. rex , O. casus and O suitius were described from Madeira-Mamoré, at the border between the Brazilian states of Mato Grosso and Rondônia. Chamberlin (1914) pointed out that O. rex belongs to the forms closely allied with O. scabricauda but O. rex differs from O. scabricauda in having the tergites rugose, in having no tarsal spur on legs 20, and by the large body size (70 mm). Otostigmus rex is close to O. suitius , O. casus and O. samacus in having margination on tergites 5–21, by the presence of one tarsal spur on legs 2–19, by complete paramedian sutures from tergites 5–20, by absence of sternite sutures and by coxosternal tooth-plates with 4+4 teeth. The only significant difference is tergites 1–8 smooth in O. rex , O. suitius and O. casus , and tergites 1–2 smooth in O. samacus . Therefore, O. rex is hereby considered as a junior synonym of O. suitius .

Figures

FIGURES 20 – 21. Otostigmus (P.) rex. Holotype MCZ IZ no. 1476 (14535). 20. Habitus, (dorsal view). 21. Habitus, (ventral view). Scale bars 10 mm.