PROCEEDINGS OF THE UNITED STATES NATIONAL MUSEUM issuea by (he SMITHSONIAN INSTITUTIONU. S. NATIONAL MUSEUM Vol. 98 Washington: 1948 No. 3225NEW PEMPHILIDINE WASPS FROM SOUTHERN NIGERIA By V. S. L. Pate The present paper is a report on a small but very interesting col-lection of pemphilidine wasps (family Sphecidae) made by J. C. Brid-well in southern Nigeria. The types of all the new species are in theUnited States National Museum.Genus ENCOPOGNATHUS KohlThis widely distributed genus, whicli reaches its maximum specificdifferentiation in Africa, is represented in the Ethiopian Region byonly the nominate subgenus.^ The following key will serve to separatethe eight known species : KEY TO SPECIES OF THE SUBGENUS ENCOPOGNATHUS 1. Postscntellum armed posteriorly with a translucent lamella, or bilobate; abdo-men more or less elongate. {Brownei group) 2Postscntellum simple, unarmed posteriorly ; abdomen relatively short and com-pact. (Braueri group) 52. Postscutellum bilobate, produced backward on each side in form of a thick,opaque, trigonal laminate plate (Southern Rhodesia) _chirindensis (Arnold)Postscutellum furnished with a translucent lamella around posterior andlateral margins 33. Abdomen with first three tergites coarsely rugosopunctate, fourth and fifthtergites more sparsely punctate; postscutellum yellow (Kenya to SouthernRhodesia) brownei (Turner)Abdomen with first three tergites impunctate; postscutellum black 44. Abdomen with fourth and fifth tergites granular to finely pustulate. Femaleswith only middle tibiae yellow ; pygidium yellow at base, ferruginous atapex (Belgian Congo) granulata (Arnold) iPate, V. S. L., On the taxonomy of the genus Encopognathus. Lloydia (Cincinnati),vol. 6, pp. 53-76, 1943.788793?48 149 150 PROCEEDINGS OF THE NATIONAL MUSEUM vol. MAbdomen with fourth and fifth tergites finely sparsely acupunctate. Femaleswith all tibiae and tarsi light yellow; pygidium wholly ferruginous. Maleswith fore femora armed beneath with a retrorse spine ; fore metatarsi irregu-larly laminate ; scape irregularly widened and angulate subapically ; pedicelproduced into an acuminate lateral process (Nigeiia).acanthomerus, new species5. Front armed between antennal sockets with a short, porrect, lamelliformtooth; postscutellum bisected by a carinule; abdomen black with tergitesclosely punctured, the first two quite coarsely so ; second stemite verycoarsely and sparsely punctate; pygidial area coarsely, closely punctate(Southern Rhodesia)? rhodesiana (Arnold)Front simple, unarmed; postscutellum not bisected by a carinule; abdomenimpunctate or finely punctured at most 66. Abdomen black, the second and fourth tergites with yellow fasciae, the thirdwith lateral spots, the fifth tergite wholly and the pygidium largely, yellow ; smooth, shining, finely and sparsely punctate, but fifth tergite much morestrongly and closely punctate than preceding tergites ; the pygidium coarselyclosely punctate (Senegambia) braueri (Kohl)Abdomen red, not maculated with yellow; fifth tergite not appreciably morecoarsely punctate than preceding tergites 77. Scutellum longitudinally striatorugose ; eyes separated at their nearest pointby a distance equal to three-fourths length of scape ; postorbital carina con-tinued onto the posterior margin of head (Natal) rugosopunctata TurnerScutellum with large scattered and well-separated variolate punctures; eyesseparated at their nearest point by a distance equal to less than one-halflength of scape ; postorbital carina not continued onto posterior margin ofhead (Nigeria) bridwelli, new speciesENCOPOGNATHUS (ENCOPOGNATHUS) BRAUERI (Kohl)Crabro (Encopognathus) Braueri Kohl, Ann. Naturhist. Hofmus. Wien, vol. 11, p. 486, fig. 89, 1896 ( 5 ; Senegambia).Tihyreopusl (Encopognathus) Braueri Abnold, Ann. Transvaal Mus., vol. 11,p. 346, 1926.Encopognathus (Encopognathus) braueri Pate, Lloydia, vol. 6, pp. 75, 76, 1943.This, the genotypic species, is known from only the unique femalefrom Senegambia. The finely punctate, black, maculated abdomenreadily separates hraueri from the following three species.ENCOPOGNATHUS (ENCOPOGNATHUS) RUGOSOPUNCTATA TamerEncopognathus rugosopunctatus Tubnbhi, Ann. Mag. Nat. Hist., ser. 8, vol. 9,p. 419, 1912 ( 5 ; Durban, Natal).Tlhyreopus] (Encopognathus) rugosopunctatus Abnold, Ann. Transvaal Mus., vol. 11, p. 345, 1926.Encopognathus (Encopognathus) rugosopunctatus Pate, Lloydia, vol. 6, p. 75,1943.The bright red, immaculate, finely punctate abdomen distinguishesfugosofunctata from all other members of the hraueri group exceptbridwelli. The diiferential characters separating the present speciesfrom hridwelli have been presented in the foregoing key to species. NEW WASPS FROM SOUTHERN NIGERIA?PATE 151 If all the pemphilidine wasps were to be placed in one blanketgenus Crabro, as Arnold proposes, it would be necessary to renamethis species inasmuch as it would then be a homonym of Taschenberg's1875 Venezuelan species and also Provancher's 1882 Canadian form.ENCOPOGNATHUS (ENCOPOGNATHUS) BRIDWELLI,* new species FiGUBE 16, mThe superficial habitus of hndwelli is very similar to that of Tur-ner's Natal I'ugosopunctata^ from which it may be differentiated bythe variolate sculpture of the scutellum and the narrower front. Inaddition, the postorbital carinule of hridwelli is not continuous ontothe vertex and the recurrent vein of the fore wing is received by thesubmarginal cell three-fifths of the way from its base, whereas inrugosopwnctata the postorbital carinule is continuous dorsally on thevertex while the recurrent vein is received by the submarginal cellonly two-fifths of the way from its base.Type.?Female; Oloke-Meji to Ibadan. Lagos, southern Nigeria.(J. C. Bridwell : U. S. N. M. No. 58083.)Female.?Length 8 mm. Black; the following stramineous: Basalhalf of mandibles (remainder red), scapes except for a small blackspot behind ; postscutellum with a small lateral spot on each side ; foreand middle femora with a small spot at apex ; all tibiae on outer faces; all tarsi except last segment. Fulvous : Apex of clypeal lobe ; pronotaltubercles; fore femora; all tibiae beneath; last segment of all tarsi;trophi. Abdomen bright ferruginous. Wings clear hyaline, with afaint cloud in marginal cell ; veins and stigma brunneous.Head fulgid; clypeus except bevel, and inner orbits with a narrowband of silver}^ sericeous pile ; temples with a thin vestiture of puberu-lent silvery hair. Front in scapal region strongly concave, impunc-tate, width at narrowest point about three-sevenths (0.436) the lengthof scape; upper front and vertex with scattered, irregular, coarse,variolate punctures; supraorbital foveae large, distinct, ovate, im-marginate; ocelli in a curved line, the ocellocular line three-fourthsthe postocellar distance; postorbital carinule sharp, distinct, but notfoveolate anteriorly or continuous above and separating the vertexfrom the occipital region, though with a low transverse ridge there mediall}'^; temples and occiput very finely punctulate. Antennae withsockets contiguous to nearest lower inner orbits; scapes simple, sub-cylindrical, ecarinate, about six-tenths the vertical eye length ; pedicelobterete, seven-tenths the length of first flagellar article; fiagellum ? After .T. C. Bridwell, who collected the type of this and other species described in thisreport. 152 PROCEEDINGS OF THE NATIONAL MUSEUM vol.98 simple, second segment four-fiftlis the length of first. Clypeus (fig.16, m) finely punctiilate, median length almost three-eighths (0.363)the vertical eye length; disc flatly tectate, bisected by a low keel whichends in the gently declivous, glabrous, polite, impunctate, low trigonalbevel of the median lobe, the apical margin of which is truncatemedially, laterally on each side with two teeth.Thorax subfulgid; with a thin vestiture of decumbent silverypuberulent hair, which is most noticeable on mesopleura. Pronotumshort, anterior dorsal margin bluntly carinate except medially, humeribluntly dentate, tubercles edentate ; dorsal face traversed by a trans-verse foveolate furrow. Mesonotum and scutellum with coarse, scat-tered, variolate punctures throughout, the latter with lateral edgesvery weakly margined; postscutellum finely rugidose, simple, withoutlaminae or lobes. Mesopleura coarsely rugosopunctate above to finelypunctate below; metapleura with a few horizontal rugulae. Pro-podeum : Dorsal face with a row of large areoles radiating from an-terior margin; posterior face with a broad, trigonal discal areole,laterad of which the surface is traversed by horizontal rugae; lateralcarinae well developed below, obsolescent above, simple and not bifur-cate below ; lateral faces finely acupunctate.Legs stout, simple. Fore metatarsi flattened, with a pecten of short, stilf spines. Middle and hind tibiae with outer faces spinulose.Longer hind tibial calcar eight-tenths the length of hind metatarsus.Forewings with marginal cell about tliree times as long as broadand broadly truncate at apex; both radius and cubitus with secondabscissae almost eight-tenths (0:78) the length of first abscissae.Abdomen fulgid ; with a thin vestiture of decumbent silvery puberu-lent hair. Tergites with fine scattered acupunctures and fine micro-scopic transverse aciculation; fifth tergite with puncturation slightlymore distinct than preceding tergite; ultimate tergite with a broad,equilaterally trigonal pygidial area, the disc polite, with a few coarsepunctures. Sternites with fine microscopic cancellate sculpture.This Nigerian species is known from only the unique female de-scribed above.ENCOPOGNATHUS (ENCOPOGNATHUS) RHODESIANA (Arnold) T[?iyrcopus] {Encopognatlnis) vhirindensis Arnold, Occ. Pap. Rhodesian Mus.,No. 1, p. 19, figs. 10, 10a, 1932 (5,5; Southern Rhodesia ; Spongweni).Encopognathus {Encopoynathus) rhodesiunus Pate, LU)ydia, vol. 6, p. 75, 1943.The porrect lamelliform frontal tooth, the coarsely punctate firsttwo segments of the immaculate black abdomen, and the carinate post-scutellum distinguisli this Southern Rhodesian form from all the othermembers of the hraueri group. NEW WASPS FROM SOUTHERN NIGERIA?PATE 153ENCOPOGNATHUS (ENCOPOGNATHUS) CHIRINDENSIS (Arnold) T[hyreopus] (Encopo(/nathus) cJiirindensls Arnold, Occ. Pap. Rhodesian Mus.,No. 1, p. 17, figs. 11, 11a, lib, 1932 (5,5; Southern Rhodesia : Chirinda Forest,tunneling in a shady, sandy path).Encopognathus (Encopognathus) chirindensis Pate, Lloydia, vol. 6, pp. 75, 76,1943; 9t S ; Southern Rhodesia: Chirinda Forest; Mount Selinda).The thick, opaque postsciitellar lobes differentiate chirhidensis fvomall other members of the hrownei group. This is apparently one of thecommonest species of the subgenus.ENCOPOGNATHUS (ENCOPOGNATHUS) BROWNEI (Turner)Encopognathus Brovnei Txjrnek, Ann. Mag. Nat. Hist., ser. 8, vol. 10, p. 106,1017 ( 9 ; Kenya : Tana River, 3.0(X) feet, near Mount Kenya).T[hyreoptis] {Encopognathus) Brownei Arnold, Ann. Transvaal Mus., vol. 11,p. 346, 1926; Ann. Transvaal Mus., vol. 12, p. 122, 1927 {egrcgius Arnold, 1926,placed as a synonym of brownei Turner, 1917).T[hgreopiis] (Encopognathus) egrcgius Arnold, Ann. Transvaal Mus., vol. 11,p. 347, figs. 4a, 4b, 1926 ( 9 ; Southern Rhodesia : Sawmills ; Rhodesdale, nestingin sandy banks).Encopognathus {Encopognathus) 'brownei Pate, Lloydia, vol. 6, pp. 75, 76, 1943 ( 9 ; Southern Rhodesia: Sanyati Valley).This and the following two species liave the postscutellum armedwith a translucent lamella around the lateral and posterior margins.The coarsely punctate first three abdominal tergites immediately sep-ai'ates hrownei, which ranges from Southern Rhodesia northward toMount Kenya in east Africa, from both granulata and acanthomerv.s.ENCOPOGNATHUS (ENCOPOGNATHUS) GRANULATA (Arnold) T[hi/reopus] {Encopognathus) granulatus Arnold, Ann. Tran.svaal Mus., vol. 11,p. 348, 1926 ( 9 ; Belgian Congo: Penge).Encopognathus {Encopognathus) granulatus Pate, Lloydia, vol. 6, pp. 75, 76, 1943.The fourth and fifth tergites of this species are covered with small,oval, warty granules. This type of sculpture is very distinctive andof rare occurrence in the sphecoid wasps and serves to differentiateyranidata from all other species of Encopognathus . If all pemphilid wasps were to be placed in the single portmanteaugenus Cnthro^ as Arnold proposes to do, the present species would re-quire another name inasmuch as it would then be a homonym of theEgyptian Crahro granulatus Walker, 1871.ENCOPOGNATHUS (ENCOPOGNATHUS) ACANTH0MERUS,? new specieiFigure 16, b, ;, ?The present Nigerian species is evidently most closely related togranulata but lacks the granular to finely pustulate sculpture on the ' &Ka.vOa, spine +jii;p6i, thigh; in allusion to the rctrorsely spined fore femora of the males. 154 PROCEEDINGS OF THE NATIONAL MUSEUM vol. ?8fourth and fifth abdominal tergites, which is such a characteristicfeature of the Belgian Congo form. In addition, the fore femoraof the males are armed beneath with a long retrorse spine and alsohave the antennal scape and pedicel very curiously modified.Type.?Male; Oloke-Meji to Ibadan, Lagos, southern Nigeria. (J.C. Bridwell ; U. S. N. M., No. 58034.)MoHe.?Length 5 mm. Black ; the following citrinous : Scapes savefor a black spot behind ; pronotal tubercles ; fore femora with a nar-row stripe above and a broad stripe lengthwise below; fore tibiae;middle tibiae on outer faces ; hind tibiae with a broad stripe lengthwiseon outer faces; all tarsi. Mandibles dark red. Fulvous: Forefemora save for yellow maculation ; middle tibiae on inner faces ; lasttwo abdominal segments.Head fulgid; clypeus with a silvery sericeous appressed pile;temples with a thin vestiture of decumbent puberulent silvery hair.Front with scapal area concave, shining, impunctate, inconspicuouslyand transversely strigose; upper front and vertex with coarse, ir-regular pits and punctures, which somewhat obscure the supraorbitalfoveae; ocelli in a low triangle, the ocellocular line three-fourths thepostocellar distance ; posterior orbits margined by a carinule, which isweakly foveolate anteriorly and which is continuous across vertexbehind posterior ocelli; temples and area between postorbital andoccipital carinules finely punctulate. Antennae (fig. 16, &) withscapes irregular, angulate before apex, almost one-half (0.45) thevertical eye length; pedicel two-thirds the length of first flagellararticle, with a long lateral acuminate appendix ; flagellum with firstsegment angularly widened below toward apex and twice the lengthof second segment; last segment twice the length of penult article;antennocular line one-half the interantennal distance. Clypeus (fig.16, n) one-fourth the vertical eye length, finely punctulate, flat later-ally to sharply tuberculate discally; with a polite, impunctate, gla-brous, trigonal bevel from discal tubercle to apex of the sex-dentatemedian lobe. Mandibles with apices slender, acuminate ; lower mar-gins distinctly excised.Thorax fulgid ; with a thin and inconspicuous vestiture of puberulentsilvery pubescence, which is most noticeable on epicnemium and lowermesopleura. Pronotum short, anterior margin transversely carinate,humeri and pronotal tubercles sharply dentate. Mesonotum withscattered, coarse, variolate pits and punctures ; suture between mesono-tum and scutellum deeply impressed ; scutellum with coarse variolatepunctures, lateral edges sharply margined; postscutellum with ante-rior margin arcuately carinate, surface concave, bisected by a carinule,lateral and posterior margins edged with a translucent, brownish,ecarinulate lamina, which is emarginate medioposteriorly. Meso- NEW WASPS FROM SOUTHERN NIGERIA?PATE 155pleura and metapleura with coarse, close, variolate punctures. Pro-podeum with dorsal and posterior faces coarsely areolate andsculptured; lateral carinae well developed, bifurcate below; lateralfaces microscopically granulose.Forelegs with femora (fig. 16, j) stoutly subfusiform, angulatedistally below and armed with a long retrorse spine; tibiae flattenedbeneath ; metatarsi distorted-laminate. Middle and hind legs simple,the tibiae echinulate on outer faces ; longer hind tibial calcar one-halflength of hind metatarsi.Forewings with marginal cell three times as long as wide andbroadly truncate at apex ; radius with second abscissa eight-tenths thelength of first abscissa; cubitus with first abscissa almost two-thirds(0.65) the length of second abscissa.Abdomen fulgid ; with a very inconspicuous vestiture of fine puberu-lent silvery hairs. Tergites almost impunctate but with fine micro-scopic transverse aciculation. Penult tergite with a few coarse scat-tered punctures; last tergite with a subtrapeziform pygidial area, thedisc coarsely punctate. Sternites practically impunctate; hypopy-gium with apex entire.Allotype.?Female; topotypical. Same data as type. (U. S. Na-tional Museum collection.)FeTiiale.?Length 6 mm. The following features are solely thosenoteworthy of difference from those given in the foregoing descrip-tion of the male (type) :Livery the same, but base of mandibles yellow.Head with clypeal lobe essentially the same, the median clypeallength one-fourth the vertical eye length. Antennal scapes one-halfthe vertical eye length ; simple, cylindrical, ecarinate ; pedicel simple,obterete, four-fifths the length of the first flagellar article ; flagellumsimple, first two segments subequal in length, ultimate segment twicethe length of penult article. Ocellocular line almost six-tenths (0.571)the postocellar distance.Thorax and propodeum essentially the same ; the pronotum with an-terior margin more strongly carinate ; humeri and pronotal tuberclesmore strongly dentate.All legs simple. Fore metatarsi flattened, rather wide, and with apecten of short stiff spines.Abdomen generally as in male, but pygidial area broad, equilaterallytrigonal, the disc with a few coarse, scattered punctures. Secondsternite medially with a sharp, transverse, arcuate ridge on each sideof median line.This distinctive Nigerian species is known only from the unique pairdescribed above. 156 PROCEEDINGS OF THE NATIONAL MUSEUM vol.98ARNOLDITA,* new genusThyreopus (Tracheliodes) [nee Morawitz] Arnold, Ann. Transvaal Mus., vol. 11,p. 349, 1926.Crabro (species-group Tracheliodes) [nee Morawitz] Arnold, Ann. TransvaalMus., vol. 20, p. 137, 1940; Occ. Pap. Nat. Mus. Southern Rhodesia, vol. 2,No. 2, p. 28. 1944.Genotype.?Thyreopus {Tracheliodes) perarmatus Arnold, 1026{^Arnoldita perarmata (Arnold) ).The three-segmented labial and six-segmented maxillary palpi dif-ferentiate Arnoldita from all other genera of pemphilidine wasps withthe exception of Tracheliodes and Enoplolindenius. From both ofthese, the present genus ma}' be distinguished by its slender, elongate,clavate abdomen, the well-developed sternauli and hypersternauli onthe mesopleura, the porrect frontal process, and the 11-segmented an-tennae of the males. In addition, the transversely carinate pronotum,the vertical carina on the mesopleura before the middle coxae, thestrongly flanged and foveolate occipital carina, and the carinate an-tennal scapes separate Arnoldita from Tracheliodes; while therounded, ecarinate mesosternum, the incompletely margined scapalsinus, the incomj^lete occipital carinule, and the protean-shaped man-dibles distinguish the present genus from the New World entityEnoplolindenius.Generic characters.?Small, slender, fulgid, impunctate or at bestfinely punctate forms. Head broad, transversely subrectangular inboth anterior and dopsal aspects; eyes naked, very large and broadbelow, which more coarsely faceted anteriorly than posteriorly, innerorbits either strongly convergent below or more or less arcuate ; malarspace wanting. Front on anterior vertical aspect generally narrow,and with a rather deep, incompletely marginate scapal sinus bisectedby a longitudinal carinule from which arises just above antennalsockets one, or rarely two, large, porrect, protean-shaped processes.Vertex flat, nitidous, generally impunctate; supraorbital foveae pres-ent and generally distinct; ocelli moderately large, arranged in anequilateral triangle. Temples very well developed, ecarinate, butposterior orbits either paralleled or not by a marginate groove;occipital carina very well developed, strongly flanged, foveolate an-teriorly, but neither a complete circle in extent nor attaining the hy-l>ostomal carinule bordering the broad, shallow, scyphate oral fossa.Antennae situated low on face on dorsal margin of clypeus, the socketscontiguous to each other and either contiguous to, or well separatedfrom, the nearest lower inner orbits ; 12-segmented in the females, andwith only eleven apparent segments in the known males ; scape slender, * It gives me great pleasure to dedicate this distinctive genus to Dr. George Arnold,director of the National Museum of Southern Rhodesia, in recognition of his outstandingworlf on the aculeate Hynienoptera of Africa. NEW WASPS FROM SOUTHERN NIGERIA?PATE 157 elongate, unicaiinate lengthwise; flagellum generally simple in fe-males, but in males with the first three segments apparently ankylosed.Clypeus reduced laterally to a mere line, medially with a very shortlobe which is diversely dentate or excised apically. Maxillary palpiwith six, labial palpi with three, segments. Mandibles slender, veryelongate, strongly decussate; apices either simple and acuminate,bidentate or truncate ; inner margins dentate or edentate ; lower mar-gins entire. Females without a psammophore.Thorax compact, perfulgid, finely punctate at most. Pronotumrelatively elongate, transverse, anterior dorsal margin furnished with asharp, transverse carina which descends vertically at the humeri ; thedorsal surface with a transverse torus and frequently with a row oflarge foveae. Mesonotum polite, impunctate, though sometimes withpits or foveae anteriorly; suture between mesonotum and scutellumfoveolate; axillae small, lateral margins rounded; scutellum polite;postscutellum short, transversely linear, longitudinally striate. Meso-pleura more or less horizontally striate, generally impunctate; pre-pectus sharply margined anteriorly ; episternal suture, hypersternauli,and sternauli present, well developed and strongly foveate, and a ver-tical carina before the middle coxae. Metapleura finely sculptured.Mesosternum rounded, ecarinate anteriorly. Propodeum fulgid ; dor-sal face with a more or less well defined trigonal enclosure; lateralcarinae present and well developed along posterior and dorsal faces;posterior face with a discal areole.Forewing with marginal cell narrow and elongate, four times as longas wide, truncate at apex and with a small appendiculate cell ; radialvein with first abscissa one-half the length of second abscissa ; trans-verse cubital vein oblique, inclivous, one-third the length of secondabscissa of cubitus; cubitus with first abscissa two-thirds the length ofsecond abscissa and somewhat angled backward at point of receptionof recurrent vein. Hind wing with anal lobe distinctly shorter thanthe short submedian cell.Legs simple or variously modified. Fore trochanters slender, ob-terete, about one-half the length of fore femora. Middle tibiae with acalcar in both sexes.Abdomen slender, elongate, clavate ; nitidous, immaculate black, andimpunctate or at best very finely punctate. First segment elongate,petioliform and more or less nodose at apex. Tergites with basal aca-rid chambers, the ultimate in the females with a fully marginate pygid-ial area, which is more or less narrowed and excavate apically, the discshallowly concave, the lateral margins glabrous. Males probably with-out a distinct pygidial area.Remarks.?Although Arnold has recognized the discreteness of thepresent group, he has consistently assigned the component species to the 158 PROCEEDINGS OF THE NATIONAL MUSEUM vol. M Holarctic genus Tracheliodes. But as I have pointed out in my reviewof that myrinecotherous entity,^ Aimoldita has little in conunon withTracheliodes save the same number of segments in the labial palpi.The strongly flanged and foveolate occipital carina, the transverselycarinate pronotum, the sharply margined prepectus, the presence onthe mesopleura of a vertical carina before the middle coxae and of well-developed sternauli and hypersternauli. the well-developed lateralcarinae on the propodeum, and finally the slender, elongate, clavateabdomen of which the first segment is petioliform and more or lessnodose apically, all indicate that these African species cannot be placedin Traelieliodes without doing violence to recognized generic concepts.Instead, as predicted elsewhere,** these features attest the close relation-ship that ArnoJdita bears to the Foxita complex, of which it may beconsidered a highly specialized and aberrant member.Ethology.?Like the majority of the members of the Foxita coni-plex, the species of Arnoldita are xyloecetes. Arnold states that A.senex was bred from the abandoned burrows made by bostrychid beetlesin an old wooden post at Helenvale, near Bulawayo, Southern Rho-desia.^ All the species of Arnoldita have a relatively large, muchthickened head, with the face strikingly broad below, and the man-dibles extraordinarily large and well developed. This peculiarity isevidently correlated in some manner with the biology of these wasps : The mandibles are probably used either for excavating the burrows inwood or pithy stems, or, as in Tracheliodes s for seizing and carryingthe prey back to the nest.Distribution.?The genus Arnoldita is an entity restricted to theEthiopian Region. At present three species are known : the SouthernRhodesian forms senex and canalife/ra., and perarmata which rangesfrom the northern portion of the Belgian Congo to Nigeria. Thefollowing key will serve to differentiate these forms : KEY TO THE SPECIES OF ARNOLDITA 1. Fore femora armed below with a median tooth ; antennal sockets contiguousto nearest lower inner orbit; mesonotum with two small pits anteriorly;mandibular apices obliquely truncate, the inner margins with a large preapi-cal tooth ; front with a porrect spatulate horn, the lateral margins of whichare reflexed and the apex emarginate (Belgian Congo to Nigeria).perarmata (Arnold)Fore femora edentate below ; antennal sockets relatively remote from nearestlower inner orbit; mesonotum without two pitlike foveae anteriorly (SouthAfrican forms) 22. Mandibular apices truncate, inner margins edentate; mesonotum simple, notbisected anteriorly by a carinule ; front with two iwrrect median processes ; clypeus quinquedentate senex (Arnold ) "Lloydia, vol. 5, pp. 230-231, 1942. ?Rev. Ent. (Rio de Janeiro), vol. 13, pp. 88&-390, 1942. 'Ann. Transvaal Mus., vol. 11, p. 352, 1926. NEW WASPS FROM SOUTHERN NIGERIA?PATE 159 Mandibular apices bideutate, the inner margins with a large tooth ou basalthird; mesonotum bisected anteriorly by a carinule; front with a single,porrect, spatulate process; cl.vpeus quadridentate, the two median teethbroad and obliquely truncate canalifera (Arnold)ARNOLDITA PERARMATA (Arnold)Figure 16, i, I Tlhyreopus] (TracJieUodes) perarmatus Arnold, Ann. Transvaal Mus., vol. 11,p. 349, figs. 5, 5a-d, 1926 ( 9 ; Moho, near Lesse, Belgian Congo, Type in CongoMuseum, Tervueren, Belgium).The dentate lower margins of the fore femora and the position of theantennal sockets in relation to the nearest lower inner orbits distin-guish 'perarmata from the following two species.I have examined three female specimens of perarmata in the collec-tion of the United States National Museum, taken by J. C Bridwellbetween Oloke-Meji and Ibadan, Lagos, southern Nigeria.ARNOLDITA CANALIFERA (Arnold) FiGUKE 16, d, gOrabro [species-group Tracheliodes] canaliferus Arnold, Occ. Pap. Nat. Mus.Southern Rhodesia, vol. 2, No. 2, p. 28, figs. 29, 29a-b 1944 ( 9 ; Bulawayo,Southern Rhodesia. Type in Stevenson collection).This species is evidently somewhat intermediate between perarmataand senex. Like pera,nnata^ the front of canalifera is armed with aspatulate frontal horn but the simple unarmed fore femora readilyseparate it from that species. The much larger size and differentlyshaped clypeus distinguish canalifera at once from both seTiece andperarmata, ARNOLDITA SENEX (Arnold) Figure 16, c, c T\}iyreopus\ {Tracheliodes) senex Arnold, Ann. Transvaal Mus., vol. 11, p. 350,figs. 6, 6a, 1926 ( S ; bred from abandoned burrows of bostrychid beetles inwooden post ; Helenvale, near Bulawayo, Southern Rhodesia. Type in NationalMuseum of Southern Rhodesia).Clrabro] (species-group Tracheliodes) senex Arnold, Ann. Transvaal Mus., vol.20, p. 137, fig. 27, 1940 (Southern Rhodesia : 9 , Lupane ; S , Khamis).The present species is readily distinguished from the other membersof Amoldita by the presence of two frontal horns or processes. Thesediffer in the sexes : in the female the upper one is lamelliform but notspatulate in dorsal aspect and is angularly excised at base, while thelower one is subconical, shorter, and less porrect than that of the male ; in the male the upper process is spatulate and the lower one stronglycompressed on the lower half. The mandibular apices of the male are 160 PROCEEDINGS OF THE NATIONAL MUSEUM vol.98 simple and acuminate whereas those of the female are truncate. Thestructure of the clypeus likewise differs in the sexes.Genus LESTICA BillbergLESTICA DASYMERUS,' new speciesFigure 16, e, f, h, k, oThe peculiar conformation of the legs, particularly the fore andmiddle pair, readily diiferentiates da-'iymerus from all other speciesof the Ceratocolus section of the nominate subgenus of Lestica.Type.?Male; Oloke-Meji to Ibaden, Lagos. Southern Nigeria. (J.C. Bridwell ; U. S. N. M. No. 58035. ) Male.?Length 7 mm. Black; the following badeous : Mandibles savefor red apices; pedicel ; flagellar segments beneath ; all trochanters andtarsi ; fore tibiae with a line along posterior margins ; middle femoraand tibiae on inner faces; apical abdominal sternites. Citrinous:Antennal scapes anteriorly; pronotum with a transverse stripe broadlyinterrupted medially ; pronotal tubercles ; scutellum ; first four abdomi-nal tergites with a small spot laterally on each side; fore femora andtibiae; middle femora with a broad stripe lengthwise above and below;middle tibiae on outer faces. Wings tinged with fuscous; veins andstigma very dark brunneous.Head opaque ; subtrapeziform in anterior aspect, subquadrate indorsal aspect ; clypeus, and a narrow stripe along inner orbits, silverypubescent; lower temples with a sparse vestiture of silvery puberulenthair. Front with scapal area deeply concave, finely microscopicallypunctulate ; upper front and vertex with large, coarse, irregular, close,variolate pits and punctures; supraorbital foveae distinct, elongate,linear, cicatrose; ocelli arranged in a subequilateral triangle, theocellocular line four-fifths the postocellar distance; occipital carinavery well developed, strongly flanged, shallowly but distinctly foveo-late anteriorly, attaining the posterior angles of the oral fossa, thehypostomal carinule obtusely lobed along posterior margin. Templesvariolately pitted above, finely punctulate below. Antennae withscapes about one-half (0.52) the vertical eye length, obterete, ecarinatelengthwise; pedicel suborcate, two-fifths the length of first flagellararticle; flagellum slender, elongate, with an inconspicuous fringe ofshort silver}' hairs beneath along the tyloides, second segment nine-tenths length of first article, penult segment two-thirds length oflast article. Clypeus (fig. 16, h) with median length one-third thevertical eye length; flatly tectate; bisected by a distinct keel whichterminates in a small deflexed, polite, glabrous bevel at the apex of theproduced median lobe. Mandibles strongly incurved apically ; apicesevenly bidentate ; inner margins with a low obtuse tooth. ' ?o