PAROTOSTIGMUS. 25 
PAROTOSTIGMUS, gen. nov. 
I propose this new generic name for the American species of Centipedes which have 
hitherto been assigned to Otostigmus. A considerable number of these species have 
now been described, and they all agree amongst themselves, and differ from the Oriental 
members which belong to Otostigmus in the strict sense of the word, in having the 
anal pleure posteriorly truncate and the anal femora unarmed. 
1. Parotostigmus denticulatus, sp.n. (Tab. II. figg. 10, 10 a-c.) 
Colour (in alcohol) very variable, mostly of a greenish ochraceous tint with a bluish or reddish tinge of colour ; 
shining, sometimes strongly, with metallic lustre. 
Body slender, attenuated anteriorly and posteriorly. 
Head a very little wider than long, convex, finely punctured, without sulci. 
Antenne short, composed of 17 segments, whereof the basal 2 are naked and the rest clothed with 
pubescence of a reddish tint. 
Mazillipedes: coe lightly convex, mesially and longitudinally impressed posteriorly, faintly punctured ; 
prosternal plates wider than long, almost contiguous and parallel, bearing four sharp subequal teeth; 
femur with conspicuous sharply bifid tooth. 
Tergites finely and closely punctured, from the sixth bisulcate, all, except the last, with unraised margins, 
laterally wrinkled and marked between the sulci with two shallow, longitudinal grooves, the wrinkling 
being especially conspicuous in the posterior portion of the body; finely granular, either thickly and 
irregularly, or more sparsely, indistinctly, and subserially. 
Sternites smooth and shining, very finely punctured, not sulcate, but marked more or less distinctly with four, 
an anterior and posterior median and two lateral, impressions. 
Anal somite: tergite with raised margins, not sulcate, mesially impressed posteriorly ; pleure thickly covered 
with larger and smaller pores, produced posteriorly into a smooth blunt process which projects a little 
beyond the lateral margin of the tergite, without trace of spines; sternite with converging margins, 
rounded angles, and straight posterior border, mesially impressed ; /egs without spines, of moderate 
length, the femur thicker distally than proximally, claw basally spurred ; tarsus unspined. 
Legs: claws spurred, proximal tarsal segment with a single spine, first pair of legs with an anterior tibial 
spine ; in the posterior part of the body the legs are sometimes finely granular proximally. 
Length up to 56 millim. 
Hab. Mexico, Amula 6000 to 7000 feet, and Omilteme 7000 to 9000 feet, both in 
Guerrero (H. H. Smith). 
Several specimens, found under rotting wood in clearings and in the forest. 
Judged by the formation of the dorsal plates, the species of this genus may for con- 
venience be divided into two sections—the first comprising those in which the tergites, 
at least in the hinder half of the body, have elevated margins, and the second those in 
which all the tergites, except the anal, have simple margins. Into the former division 
fall Otostigmus scabricauda (Humb. & Sauss.) (=O. appendiculatus, Porat), from Brazil 
and Ecuador; O. inermis, Porat, from Buenos Ayres; 0. occidentalis, Meinert, from 
Hayti; O. brasiliensis, Meinert, from Bahia; O. sudcatus, Meinert, from Monte Video; 
O. kerviliei, Karsch, from Ecuador; and 0. spiculiferus, Pocock, from St. Vincent. 
Whereas to the latter section belong 0. limbatus, Meinert, from Buenos Ayres and 
Brazil, and the Mexican species above described. 
BIOL. CENTR.-AMER.. Chilop., January 1896. E 
