Table Of Content

HYM. RES. J. Vol. 4, 1995, pp. 121-136 The Wasp Genus Tachytella Brauns, 1906 (Hymenoptera: Sphecidae) WOJCIECH PULAWSKI J. California Academy of Sciences, Golden Gate Park, San Francisco, California 94118, USA Abstract.—ThesouthernAfricangenus Tachytella Brauns includesaurcopilosa Brauns, 1906 (western South Africa) as well as two new species: heliophila (western Namibia) and nama (southern Namibia, northwesternSouth Africa). A lectotype is designated for Tachytella aureopilosa var. nana Arnold, 1936, the latter name being synonymized with Tachytella aureopilosa Brauns, 1906. The genus is redescribed using previously known and newly discovered characters, a key to the species is provided, and phylogenetic relationships between the species are discussed. —INTRODUCTION the mandibular posterior margin; the General. Tachytella Brauns, a little two portions differ in size, the distal one known genus from southern Africa, was —being higher than the basal one; thought to be monotypic until now. Spec- condylar ridge: arises from the condyle, imens are rarely collected (Bohart and extends distad, and forms the basal por- Menke 1976, for example, knew of only tion of the posterior mandibular mar- six). A decade ago, I discovered an unde- gin; it is angulate distally in many Lar- scribed species in materials from the State —rinae; Museum Windhoek that Ole Lomholdt, condyle: mandibular articulation on the then at the Zoological Museum, Copen- —occipital side of the head capsule; hagen, kindly had transshipped to me. notch: an emargination on the posterior During our expedition to Namibia in 1990, margin, delimited basally by the con- Maximilian Schwarz and I collected spec- dylar ridge and distally by the expand- imens that represented another new spe- —ed portion of the adductor ridge; cies. These findings prompted me to re- posterior margin: extends between the vise the genus. I follow the format used condyle and mandibular apex; called for my revisions of Kohliella Brauns, Holo- externoventral margin by Bohart and tacfn/spliex de Beaumont, and Gastrosericus Menke (1976) and lower margin by Spinola (Pulawski —1991, 1992, 1995). Michener and Fraser (1978); it actually Technical Terms. Most morphological consists of two components: the con- terms follow Bohart and Menke (1976), dylar ridge basally and the adductor but the mandibular terms are taken from ridge distally (the term posterior is pre- Michener and Fraser (1978). The following ferred because the head is hypognath- terms are here redefined for convenience: ous, and this edge is thus oriented pos- terad); Clypeal lobe: the projecting medioventral portion of the clypeus. Sternum, tergum: shortened terms for gastral sternum, gastral tergum. Mandible: — Vertex: adductor ridge: extends distad from the — adductor swellings (on the inner side) length: the distance between a hind- and gradually becomes visible from the ocellus and an imaginary line connecting outside, constituting the distal part of eye hindcorners (i.e., the point where the 122 Journal of Hymenoptera Research inner and the posterior portions of the or- gate scars (Figs. 8, 12, 20), the only rem- b—it meet); nant of a lens being a narrow, translucent width: the shortest interocular distance band along the scar's outer margin (the in the ocellar region. band is broadly interrupted on the scar's — posterolateral or lateral side, depending Origin of Material. The 29 specimens on its orientation). Within the tribe, Tach- beexeanmicnoelldectaepdpasroenftarl.yInasrteituatlliontahlatorhpaevre- yftoeulrlacchaarnacbteerrs:ecognized by the following sonal collections in which the material is 1. The frons has a median, slightly deposited are abbreviated in the text as raised, flat area that is delimited by a lat- follows (names of contact persons are giv- eral sulcus (Figs. 6, 10, 18, 22, 28, 31), the en in parentheses): sulci being subparallel and close to the or- AMG: Albany Museum, Grahams- bits. Similar sulci are found in some An- town, South Africa (Friedrich cistromma W. Fox, e.g., capax W. Fox, and W. Cess). in less specialized Parapiagetia Kohl such BMNH: British Museum (Natural His- as genicularis (F. Morawitz) and odontosto- London, current nonstat- ma (Kohl), in which however, the frons is tory), utory name: The Natural Histo- not raised. ry Museum (Loraine Ficken). 2. The pronotal collar is rounded and CAS: California Academy of Sciences, reaches the scutum level, a condition also San Francisco, California (Woj- found in some Gastrosericiis, e.g. baobabiciis ciech J. Pulawski). Pulawski and eurypus Pulawski. Tachytel- FSCA: Florida State Collection of Ar- la, however, has three submarginal cells, thropods, Gainesville, Florida whereas Gastrosericiis has two. (Lionel A. Stange, James R. Wi- 3. The submarginal cell III in the fore- ley). wing is essentially rhomboidal (Fig. 1), a MS: Maximilian Schwarz, Ansfelden previously unused character, with the an- bei Linz, Austria (personal col- terior and posterior margins equal in lection). length or nearly so; the proximal and dis- SAM: South African Museum, Cape tal margins are weaklv sinuous, almost Town, South Africa, including straight, nearlv parallel to each other. G. Arnold collection previously 4. The hindwing jugal lobe is short and housed in Bulawayo, Zimbabwe ends well before crossvem cu-a; conse- (Margie A. Cochrane, Vincent B. quently, the jugal and anal excisions are A Whitehead). widely separated (Fig. 1). similar con- FMP: Transvaal Museum, Pretoria, dition is found in some specialized Gastro- South Africa (Ilema Fourie). sericiis such as braunsi Arnold, herero Pu- USNM: Smithsonian Institution, Na- lawski, and pulchellus R. Turner (Pulawski tional Museum of Natural His- 1995). — tory, Washington, D.C. (Arnold Description. Bohart and Menke (1976) S. Menke). regarded Tachytella as monotypic and, consequently, considered as generic some Genus Tachytella structures that are found only in aureopi- Tachytella Brauns, 1906:56. Type species: Tach- lsouscahbumtalneotstirnuctthuereosthaesrtthewoedsepnetcaiteesi(ne.nge.r, ytella aureop—ilosa Brauns, 1906, by monotypy. mandibular margin, dentate clypeal free Diagnosis. Tachytella is a member of margin, and sterna VI-VIII with dense, Larrini (Bohart and Menke 1976) and thus erect setae). They thought that the prono- has the hindocelli modified to flat, elon- tal collar not closely appressed to scutum Volume 4, 1995 123 mm mm 0.5 0.25 Figs. 1-3. Some of the generic characters of Tachytella. 1, fore and hindwing ofaureopilosa (drawn from the holotype, the model Bohart and Menke 1976, used for their illustration); arrows indicate third submarginal cell, jugal excision, and anal excision. 2, anterior part of thorax ofaureopilosa (arrow indicates pronotum). 3, foretarsusof female nama. 124 Journal of Hymenoptera Research also was a generic character, but in fact it cu-a vertical (not inclined). Forecoxal apex is only individual. The following rede- notexpanded into process. Hindcoxal dor- scription takes into account the three spe- sum: inner margin not carinate. Hindtibia cies now recognized and also some struc- not margined. Forebasitarsus and apical tures not considered previously. Included tarsomeres without ventral spines. Claws are those features that vary within other in each pair equal in size. Hindtarsomere Larrini but are universal in Tachytella. II long (0.6-0.7 X hindtarsomere I). Base Labrum flat, not emarginate apically, of tergum I variable: with or without not or barely protruding beyond clypeal short, oblique carina that extends from free margin; prementum convex but not each anterolateral corner. Lateral carina of compressed laterally; stipes nearly flat. tergum I complete, reaching tergal hind- Mouthparts not elongate. Paramandibular margin. Tergum II not carinate laterally. process broadly separated from back side Body without erect setae (except setae on of clypeus (mandibular socket open). Pos- apical sterna in male of aureopilosa); those terior mandibular margin notched; notch on propodeal dorsum inclined obliquely delimited proximally by angulate apex of toward head. condylar ridge, and distally by marked, Female. Inner mandibular margin with roundly expanded distal portion of ad- tooth. Forecoxa not carinate anteriorly, ductor ridge. Clypeus produced into mes- venter slightly convex; outer surface of al lobe, free margin of lateral section con- foretibia withoutpreapical spines. Foretar- cave. Antennal socket narrowly separated sus with rake that consists of stiff, flat- from frontoclypeal suture. Inner orbits tened, widely spaced spines (four on for- convergent above. Frons flat, with no gla- ebasitarsus, two on foretarsomere II); tar- brous swelling above each antennal sock- someres IV: length more than apical et. Hindocellar scars elongate, broadly di- width, apicoventral margin emarginate; verging anterolaterad (their long axes tarsomeresV: apicoventral margin slightly forming an angle of about 120-140°), arcuate. Claws without teeth. Tergum VI shorter than distance that separates each fairly convex: angle between lateral mar- one from midocellus. Occipital carina ef- gin of tergum and lateral margin ofpygid- faced just short ofhypostomal carina. Pro- ial plate, in side view about 30-40°. Pygid- notum anterodorsally with transverse ial plate well defined (margined laterally), groove; collar swollen, reaching level of rounded apically, sparsely punctate and scutum. Postspiracular carina evanescent, with thin, inconspicuous setae (Figs. 9, 21, about as long as midocellar diameter. Ep- 30). Sting sheaths somewhat flattened dor- isternal sulcus originating near middle of soventrally. subalar fossa, ending well before reaching Male. Foretrochanter and forefemur not anteroventral mesopleural margin; scrobal emarginate; forebasitarsus 1 with one rake sulcus absent; subalar fossa not margined spine (in basal half); outer, apical spine of below; metapleural flange not expanded. foretarsomere II shorter than foretarso- Axilla the usual shape, i.e., not expanded mere III; sterna without velvety patches; or carinate. Propodeum short, distancebe- tergum VII carinate apicolaterally, not de- tween spiracle and metanotum less than pressed apically; sterna III-VI impunctate spiracle's length; dorsum setose through- at least mesally; sternum VIII rounded out. No additional sclerites between me- apically or (some aureopilosa) minimally tasternal apex and propodeum (no "pro- emarginate. Venter of penis valve finely podeal sternum"). Forewing with three denticulate subapically (—Figs. 17, 27, 35). submarginal cells, none petiolate; recur- Character Polarization. The tribe Larri- rent veins separate or (some aureopilosa) ni, of which Tachytella is a member, con- forming shortpetiole. Hindwingcrossvein sists of two lineages, the subtribes Larri- Volume 4, 1995 125 nama nama heliophila aureopilosa aureopilosa heliophila Figs. 4a and b. Cladogramsshowing hypotheticalcladistic relationshipsofthe threespeciesofTachytella; 2: modified cleft ofinner mandibular margin, 8: penis valve with medioventral tooth. na and Tachytina (Bohart and Menke maining Tachytina as the outgroup. The 1976). The autapomorphy of Larrina is a characters found in both Tacln/telln and unique frons: the midocellus is placed in the outgroup are considered plesiom- a depression, and the transverse sweUing orphic, unless there is strong evidence delimiting the depression anteriorly joins that they have been acquired indepen- a linear swelling along the inner orbit. dently. The characters present only in The hindocelli are oriented along a trans- some Tncln/tella but nc^t the outgroup are verse line, and the transparent lens rem- regarded as apomorphic. The character nant is horseshoe-like, with the two codings are: 0. ancestral, 1 and 2. derived. branches parallel and close to each other, The following characters have been con- apparently the plesiomorphic condition sidered: within the tribe. In Tachytina, the frons is 1. Female mandible inner margin: sub- the usual plesiomorphic condition, with basal tooth: 0. well defined, 1. inconspic- no depression or swelling, but the hin- uous, obtuse (as in Tnclnjtelln nureopilosa). docelli are oriented in a V-shaped pattern The tooth is present in most members of and the lens remnant is clearly derived: the outgroup, but absent in Lnrrn Fabri- the anteriorbranch is longer than the pos- cius, the subgenus Motes Kohl of Liris Fa- terior or (in Parapiagetia) the branches are bricius, in Parapiagetia, several specialized roughly circular (open on the lateral Gastrosericus, and in two Tachysphex Kohl side). Because of the shape of the lens {nefarius Pulawski and ramses Pulawski). remnant, Tacln/tella is a member of Tach- Because of their many specializations, ytina, but its relationshipswithin the sub- none of these are likely to share a unique tribe are unclear. Bohart and Menke common ancestor with Tacln/telln, and (1976) noted that Tacln/telln resembled consequently I regard the presence of a Ancistrotnma and Larropsis Patton in the well defined mandibular tooth in Tacliy- shape of the mandible, ocellar scar, fe- tella as ancestral. male foretarsal rake, and male sternum 2. Female mandible inner margin: cleft: VIII. None of these similarities, however, 0. narrow, 1. shallow, obtusely angulate appears to be a synapomorphy. I have (as in Tacln/tella aureopilosa, 2. deep, broad found no single derived character linking (as in Tacln/tella nama). A cleft is present Tacln/telln with any of the other nine gen- and narrow in most Larrinae (including era of the subtribe. For the purpose of this Tacln/tella heliophila), but absent in Larra, analysis, I regard the Larrina and the re- the subgenus Motes of Liris, Dalara Ritse- 126 Journal of Hymenoptera Research 9 aureopilosa Q heliophiia nama ( Fig. 5. Collecting localities of Tachytella. ma, Paraliris Kohl, Holotachysphex, many 4. Propodeum: 0. without V-shaped im- specialized Gastrosericus, Parnpiagetia geni- pression, 1. with V-shaped impression. cularis (F. Morawitz), Tachysphex nefarius The impression is unique to Tachytella au- and ramses. None ofthese is likely to share reopilosa and thus apomorphic. a unique common ancestor with Tachytel- 5. Male foretarsus: 0. tarsomere II not la, and I therefore accept that a narrow expanded, 1. tarsomere II expanded. The cleft is ancestral in the latter genus. The expanded tarsomere of Tachytella aureopi- broad, deep cleft is unique within the losa is unique within the tribe and thus tribe. apomorphic. 3. Male clypeus: 0. without longitudinal 6. Tergum I: 0. with a pair of short, bas- swellings, 1. swellings present. The clyp- al carinae, 1. carinae absent. Within Lar- eal swellings of aureopilosa are unique rini, the carinae are absent in Gastrosericus, within Larrinae and thus apomorphic. Holotachysphex, Kohliella, Parapiagetia, Tach- Volume 4, 1995 127 mm 8 0.5 f-mm mm mm 0.25 0.25 Figs. 6-9. Tachytella aiireopilosa, female. t>, head frontally. 7, clypeus. S, head dorsally. 9, pygidial plate. sii/sspchheixl,opmsiadnisv(TCaocchkvetreesllPaannzderF,ox)a.ndThLeayrraorp-e ttooootthh,, f1.ouwnidthmmeTdaichouvteenitlaralhelitoopohtihl.a Tahnids present m all other Larrini and other nama, is unique within Larrinae and thus Sphecidae (those with a petiolate gaster apomorpnic. are obvious exceptions). 1 therefore regard The following 5 characters cannot be the absence of carinae in Tachytella aiireo- polarized because both states are com- pilosa as derived. monly found in the outgroup: 7. Male gaster: 0. sternal setae all short, 9. Gena: a. thin in dorsal view, b. thick 1. setae of sterna VI-VIII long, erect. Ster- in dorsal view. nal setae are short, appressed in most Lar- 10. Mesopleural vestiture: a. not con- rinae, but long, erect on apical sterna in cealing integument, b. concealing integu- many Liris and in Tachytella aiireopilosa. ment. These species are not likely to share a sin- 11. Hindtarsomere IV: a. length about gle common ancestor. In addition, the se- 1.0 X apical width, b. length about 1.2-1.3 tal configuration c^f T. aiireopilosa is unique X apical width. and I regard it to be derived. 12. Pygidial plate of female: a. apex 8. Penis valve: 0. without medioventral with a row of setigerous punctures. 128 Journal of Hymenoptera Research mm mm 12 0.5 0.5 mm 11 mm 13 0.25 0.25 Figs. 10-13. Tachytella aureopilosa, male. 10, head frontally. 11, clypeus. 12, head dorsally with outline of vertex showing variation. 13, scape. b. apex without a row of setigerous punc- modified cleft on inner mandibular mar- tures. gin) is shared by aureopilosa and nama, and 13. Male mandible: a. inner margin an- character8 (penisvalve with medioventral gulate, b. inner ma—rgin simple. tooth) by heliophila and nama. The clado- Cladistic Analysis. Distribution of the 8 gram resulting from character 2 (Fig. 4a) polarized characters is given below: is heliophila + {aureopilosa + nama), the Number: 12345678 cladogram based on character 8 (Fig. 4b) ancestor: 00000000 is aureopilosa + {heliophila + nama). I see 11111110 no reason to p—refer one over the other. aureopilosa: Unknown. The 00000001 Life History. presence, hnealmiaop:hila: 02000001 in the female, of a foretarsal rake and a pygidial plate suggests ground n—esting. Only two derived characters are found Geographic Distribution (Fig. 5). Namib- in more than one species: character 2 (a ia and western half of South Africa. Volume 4, 1995 129 KEY TO THE SPECIES 1. Propodeal dorsum with V-shaped impression that begins behind each spiracle and ends athindmargin(impressioninconspicuousinsmallestindividuals);tergumIbasally without pair ofshort, obliquecarinae. Female: clypeus (exceptbasally) with finely, closely punctate median impressionthatseparates two unsculptured, longitudinalareas (Fig. 6); imierman- dibular margin with inconspicuous subbasal tooth (Fig. 6). Male: clypeus with pair of glabrous, longitudinalswellings, free margin with small, median tooth (Fig. 10); sternaVI- VIII with dense rows or tufts of erect setae (Fig. 15); penis valve without ventral tooth (Fig. 17) aurcopilosa Brauns - Propodeal dorsum without such impression; tergum I basally with pair of short, oblique carinae. Female: clypeal bevel without median row of small punctures; inner mandibular margin with well-defined subbasal tooth (Figs. 18, 28). Male: clypeus with no longitudinal swellings, free margin without small, median tooth; sterna without dense rows or tufts of erect setae; penis valve with ventral tooth (Figs. 27, 35) 2 2. Mesopleural vestiture conspicuous, fully concealing integument. Length of hindtarsomere IV 1.2-1.3 X apical width. Female: free margin ofclypeal lobe weakly arcuate, corner well defined but not prominent (Fig. 18); inner mandibular margin with usual, narrow cleft (Fig. 18). Male: clypeal lobe broad, nonprominent (Fig. 22); inner mandibular margin simple (Fig. 22) heliophila sp. n. - Mesopleural vestiture inconspicuous, integument easily visible. Length of hindtarsomere IV about 1.0 X apical width. Female: free margin of clypeal lobe sinuate, with prominent corner (Fig. 28); inner mandibular margin with broadly expanded cleft (Fig. 28). Male: clypeal lobe prominent, markedly narrowing anterad (Fig. 31); trimmal margin obtusely dentate (Fig. 31) nama sp. n. DESCRIPTIONS OF SPECIES (TMP), pre—sent designation, examined. New Diagnostmic characters for each species s^^y^nô^n^ym^.^^ A^s^^^Ta^chy^tê7l^lâ25a3iir(eiolpliulsotsraatinoannao:f are given the key and are not repeated ^^^^ êad), 256 (new status, listed), individually in the descriptions below. — Synonymy. Arnold (1936) described a Tachytella aiireopilosa Brauns yar. nana for specimens that had red gas- Figures 6-17 tral segments I-III, shallower V-shaped „Tnacn,o/rtre^le,lc,ataioirrei.og-i:vnial,ol,s1a,,hByrpahu.ensn,ati1i.9n.o0nn6^.:5e7rr,uHomla1oltei.y,pî•en:- itrmup'^nrccastseiornat,ohenr,tthhc,apnr,sohpao,ldlc,oawll-yd^ oermsaurmg",i•naant.de male. South Africa: Cape Province: Willow- male sternum VIII. Because these charac- more (TMP), examined.—Arnold 1923:218 ters vary individually, I regard var. nana (revision), 1930:5 (listed); Bohart and Menke as a synonym—of aiireopilosa. 1976:231 (illustration of ocelli), 253 (illustra- Description. Gena thin in dorsal view tion of male head), 255 (illustration of (Figs. 8, 12). Vertex with triangular, gla- wings), 257 (listed), 258 (illustrations of pro- brous, impunctate, dull area that extends notum and scutum), 268 (illustration of fe- f^.^^ Q^bit toward midline. Head, thorax, male foretarsus), 279 (illustration of male ^^^^^^^ ^^^ femora minutely punctate, sternum VIII), 280 (illustration of male geni- punct,ures no more ti.huan 1i d^-iaImêt.*.e,r^ a^^pâ.r.tf, talia); Gess 1981:19 (South Africa: nefting hence integument mat except for shiny probably in friable soils). Tachytellaaureo-pilosa race nana Arnold, 1936:29, clypeal swellings in male. Propodeal dor- female, male. Lectotype: male. South Africa: sum, in most specimens studied, with Cape Province: Resolution in Albany District pair of impressions that meet postero- 130 Journal of Hymenoptera Research 0.25 mm 0.25 mm 15 mm 0.1 Figs. 14-17. Tachytella aiireopilosa, male. 14, foretarsomere. 15, gastral apex in profile. 16, volsella. 17, penis valve. mesally and delimit triangular area re- throughout. Length of hindtarsomere IV sembling propodeal enclosure of most about 1.0 X apical width. Gastral seg- i Sphecidae (impressions barely visible in ment I without basolateral, oblique cari- smallest specimens, apparently a result of na. allometric growth). Propodeal hindface Mesopleural vestiture concealing integ- not ridged. Femora and tibiae setose ument.