MYRIAPODOLOGICA Virginia Museum of Natural History Vol. 8, No. 6 ISSN 0163-539 February 28, 2005 Another new telonychopine genus from western Brazil (Polydesmida: Chelodesmidae) By Richard L. Hof&nan ABSTRACT The new genus and species Dioplostemus salvatrix is described from a male collected at the headwaters of the Rio Guapore in western Mato Grosso, Brazil. The genus is related to the geograpliicaUy proximate Vanzolegulus but is distinct from that and all other known chelodesmid genera in the extremely long paramedian processes of the 6* stemuin. A revised key to the genera of Telonychopodini is provided. As sequentially treated in my three papers cited below, this initially monobasic taxon has increased to four genera largely localized in the headwater regions of the Rio Paraguay, and now augmented by a fifth in the upper basin of the Rio Guapore, Tlie new genus and species are described at this time to make the names available for use in the context of environmental/conservation programs being conducted in the headwaters region of the Rio Guapore in western Brazil with the support of Grupo Rede & Tangara Energia S.A. Millipeds collected under this initiative by Dr. Christine Strussmann were forwarded to me by Prof Dr. Joachim Adis; I am obligated to both of these colleagues for their involvement. Family Chelodesmidae Cook Tribe Telonychopodini Verhoeff Teionychopidae VerhoefT, 1951, Zool. Anz., 146: 82. Telonychopodini: Hoffinan, 1965, Pap. Avuls. Zool., 17: 252; 2000, Myriapod- ologica 7: 1; 2002, Myriapodologica 7: 113. Scanned with permission by the Virginia Tech Insect Systematics Group 2014 (www.jointedlegs.org) 60 Myriapodologica Key to genera of Telon yci iopodini 1 . Sternum of 6^ segment of males with two paramedian processes, telopodite of gonopod without soienomcre 2 - Sternum of 6^ segment flat to slightly concave, without trace of paramedian processes; prostatic groove terminating on a discrete solenomere at distal end of telopodite 3 2. Processes of 6^^ stemunt slender, digitiform, longer than their basal width (Fig.3), sternum of segment 5 with rounded setose knobs only between anterior pair of legs; prostatic groove terminating between small subapical flanges (Fig. 4) . . . Dioplostemus - Processes of 6*^ sternum scarcely longer than broad, apices turned caudolaterad; sternum of segment 5 with paramedian setose knobs between both pairs of legs; prostatic groove ending on a short lobe at about midlength of the telopodite. . .. Vanzolegulns 3. Telopodite terminating in a solenomere and two additional processes; prostatic groove carried by a ridge along the femoral region, visible only in ventral aspect Manfrediodesmus - Telopodite terminating in a solenomere and at most one additional process; prostatic groove visible only in mesal aspect 4 4. Telopodite arcuately curved dorsad (mesal aspect!), solenomere sigmoidally curved, evenly continuing distal reduction of femoral region Pantanalodesmus - Femoral region of telopodite essentially straight, apex abruptly set off as a short, broad, laminate solenomere Telonychopiis Dioplosternus, new genus Name: A neologism formed from the Greek elements di- (two) + koplos (armed) + stemon, in reference to the elongated paramedian sternal processes of the 6* segment. Diagnosis; Differing from all other known genera of Chelodesmidae by the elongate, divergent, processes of the 6^ sternum in males. The gonopod is similar to that of Vanzolegulus but differs in that the prostatic groove extends to the apex of the telopodite, its termination marked by a slight separation and flaring of the edges of Scanned with permission by the Virginia Tech Insect Systematics Group 2014 (www.jointedlegs.org) Hoffman; Dioplosternus salvairix 61 the groove. Differing also from Vanzolegulus by the presence of only one pair of paramedian sternal processes on segment 5, and by the occurrence of subcoxal sternal cones on postgonopodal segments. Comments; Although this taxon is manifestly related to Vanzolegulus, there are more than enough distinctive and singular structural traits in both gonopodal and peripheral characters to justify separation at the generic level, R.\nge: Known so far only from the type locality’ in the headwaters of the Rio Guapore, in northwestern Mato Grosso, Brazil. Species; Only the type species is known. Dioplosternus salvatrix, new species Figures 1-7 Name; A neologism derived from the Latin salvatus , with the intended meaning ‘"she who saves" in reference to the collector of the type specimen, a participant in the program “Resgate dc fauna" conducted prior to inundation of the region by a hydroelectric facility. M.aterj.ai,; Male holotype (MZUSP) from the Usina Hidroelectrica do Guapore, Vale do Sao Domingo (15.07", 32' S, 58.57 Edo. Mato Grosso, Brazil, 1 1- 1 7 August 2002, Christine Strussmann leg. Holotype; Adult male, broken into several pieces, length ca. 56 mm, width of segments 2-8 ca. 8.6 mm, thereafter gradually narrower, 8.0 mm at segments 11-16 then abruptly narrower to 19“\ LAV ratio ca. 15%. Color of recently preserved specimen overall light brown with faint purplish cast, perhaps maroon in life, legs and antennae somewhat lighter, metaterga with yellow transverse band on posterior edge, widest and most conspicuous on anterior segments, caudolateral corners of paranoia also yellowish. Head without obvious modifications, most of facial setae abraded. Collum laterally acute, marginal groove not extending to outer angle. Surface of prozona coarsely microaspcnilate, composed of numerous minute, short, transversely oriented striae: surface of metazona smooth, superficially coriarious. Stricture broad and deep, anterior edge sharply defined ventrally, less so dorsally, without costulations. Paranota large, only slightly declivent anterior comers rounded, posterior comers obtusely angular back to segment 4, thereafter broadly rounded on poreless segments, variously modified by location of peritreme on poriferous Peritremata suboviform at midbody, pore opening laterally near posterior end (Fig. 1 ); in going posteriad the Scanned with permission by the Virginia Tech Insect Systematics Group 2014 (www.jointedlegs.org) 62 Myriapodologica shape becomes more slender (Fig. 2) and provided with a fine but evident groove along its dorsal side, not occurring in other chelodesmids known to me. Metaterga with evident transverse groove, postenor edge with a single row of about 20 minute tubercles. Limbus broad, with conspicuous fringe composed of setiform processes arising from about its midwidth. Efistal half of epiproct slightly declivent: h^poproct tnangular, with a broad, shallow transverse groove near midlength. Legs attached to strongly elevated podostema, deeply indented on posterior face; essentially glabrous, at midbody about as wide as length of prefemora but narrowed perceptably in going posteriad: each sternum posterior to gonopods produced into low but distinct subconical projections mesad to the coxal condyles. Sides of metazona Dioplosternus salvathx, structural details. Fig. 1. Left paranotum of segment 9. dorsal aspect. Fig. 2. Left paranotum of 15* segment, dorsal aspect, with the longimdinal groove indicated. Fig. 3. Sternal processes of 6* segment, posterior aspect. Fig, 4, Ape.x of gonotelopodite, to show termination of prostatic groove. Scanned with permission by the Virginia Tech Insect Systematics Group 2014 (www.jointedlegs.org) Hoffman: Dioplosternus salvathx 63 Dioplosternus salvatrix^ gonopod structure. Fig. 5. Left gonopod, dorsal aspect. Fig. 6. Left gonopod- mesal aspect. Fig. 7. Left gonopod. ventral aspect with open suture between prefemur and acropodite indicated. Scanned with permission by the Virginia Tech Insect Systematics Group 2014 (www.jointedlegs.org) 64 Myriapodologica finely granular, a low thin plcurostemal carina visible on anterionnost segments. Legs moderately long, without modifications, mostly glabrous except for apical setae of the distal podomeres. Sternum of 4^*^ segment with low but prominent median process composed of two coalesced paramedian processes; sternum of segment with low, rounded, contiguous setose knobs between anterior legpair only, sternum between posterior legs flat. Gonopod aperture transversely oval, extremely large, occupying most of ventral side of prozonum and reducing anterior edge to a narrow strip; postenor side of aperture forming broad, flat plane sloping up between legs of pair and reducing the sternum to a narrow^ transverse crest, this sloping surface with five or six short carinae on each side. Gonopods large and robust, of the form show n in Figs. 5-7. Proximal end of coxosternal apodeme small and decurved; coxae subglobose, very shorten medial side, separated by sclerotizcd. subtriangular median sternal element. No coxal apophysis present, and no paracannular setae. Distal edge of coxa rounded and reflexed inward as in other tclonychopodincs. Prcfemoral region not concealed on lateral side by apical extension of coxa. Telopodite relatively short and massive, prefemur w ith a large cuneatc process bearing a smalt truncated projection at its base. Acropodite of very' simple form, a flattened to slightly concave blade, prostatic groove visible along much of its medial edge, terminating apical fy wath the edges of the groove slightly flared and separated. In ventral aspect, a distinct unsclerotized space between prefemur and acropodite is evident (Fig. 7, possibly relict of a former movable articulartion. REFERENCES Hoffman. R. L. 1965. Chelodesmid Studies. 11. The status of the milliped Teionychopus meyeri Verhoeff, and of the family name Telonychopidae. Pap. Avuls. Dept Zool. Sao Paulo, 17: 243-253, figs. 1-7. Hoflhian, R. L. 2000. A syoiopsis of the Telonychopodini. a tribe of Pantanalian chelodesmid millepeds (Polydesmida: Chelodesmidae). Myriapodologica, 7: 1- 13, figs. 1-15. Scanned with permission by the Virginia Tech Insect Systematics Group 2014 (www.jointedlegs.org) Hoffinan: Dioplostemus salvotrix 65 Hoffman, R. L. 2002. A new genus of telonychopodine milliped from Brazil (Polydesmida: Chelodesmidae). Myriapodologica, 7: 1 13-121, figs. 1-10. Address of the author: Dr. Richard L. Hoffinan Virginia Museum of Natural History' Martinsville, Virginia 241 12, USA Scanned with permission by the Virginia Tech Insect Systematics Group 2014 (www.jointedlegs.org)