Triepeolus rhododontus Cockerell, 1921

Onuferko, Thomas M. & Rightmyer, Molly G., 2024, A revision of the simplex species group of the cleptoparasitic bee genus Triepeolus Robertson, 1901 (Hymenoptera: Apidae), European Journal of Taxonomy 950 (1), pp. 1-106 : 63-68

Triepeolus rhododontus Cockerell, 1921

Figs 9D , 12K , 15D, 26

Triepeolus rhododontus Cockerell, 1921: 5 (♂).

Epeolus lectiformis Cockerell, 1925a: 623 (♀), syn. nov.

Triepeolus lusor Cockerell, 1925a: 625 (♂), syn. nov.

Triepeolus junctus Mitchell, 1962: 471 (♀, ♂), syn. nov.

Triepeolus lectiformis – Brumley 1965: 73.

Proposed common name

Red-spined triepeolus.

Diagnosis

The following morphological features in combination tell T. rhododontus apart from all other Triepeolus in the simplex species group: the mesopleura laterally do not have erect/suberect, simple setae or have only sparse, short (<¼ MOD), erect/suberect, simple setae in addition to the usual appressed, branched setae ( Figs 9D , 26A, C ); the trochanters are normal (i.e., not tuberculate) ( Fig. 9D ); the dorsum of the mesosoma and metasoma have bands of pale-yellow tomentum ( Figs 15D , 26 ); and the T1 discal patch is somewhat narrowed and/or curved posterolaterally and thus allantoid with an inverted U- or horseshoe-shaped anteromedial projection ( Figs 15D , 26A–C ). Triepeolus rhododontus most closely resembles T. obliteratus and T. oblongimacula sp. nov., but in the latter two species the axillae never (as opposed to commonly; Fig. 26C ) have reddish tips, in T. obliteratus the dorsum of the mesosoma and metasoma have bands of pale-gray to white/off-white tomentum, the legs are never (as opposed to commonly) entirely reddish orange from trochanters to tarsi, and the pseudopygidial area of the female is never (as opposed to commonly; Fig. 26D ) reddish orange, and in T. oblongimacula the T1 discal patch is broadly rounded laterally and rod-shaped.

Etymology

The specific epithet was inspired by the holotype’s (partially) red axillae, which in the original description were described as “dentiform, curved, [and] acute” ( Cockerell 1921). Rhodo- comes from the Greek ‘rhódon’ (meaning ‘rose’), and dontus comes from the Greek ‘odṓn’ (meaning ‘tooth’).

Material examined

Primary type material

USA – Colorado • ♂, T. lusor holotype; Crook ; 24 Aug. 1920; G. Sandhouse leg.; USNM 534850 • ♀, E. lectiformis holotype; Logan County; 23 Aug. 1923; G. Sandhouse leg.; USNM 534641 • ♂, T. rhododontus holotype; Wray (at the head of Dry Willow Creek ), Yuma County; 17–19 Aug. 1919; F.E. Lutz leg.; AMNH AMNH_IZC 00323955 . – North Carolina • ♀, T. junctus holotype; Lakeview , Moore County; 23 Sep. 1933; T.B. Mitchell leg.; USNM 534640 .

Secondary type material

USA – Colorado • 1 ♀, E. lectiformis paratype; Logan County; 23 Aug. 1923; G. Sandhouse leg.; CAS M.G.R. Database No. 1438 . – North Carolina • 1 ♀, T. junctus paratype; Burgaw Savannah ; 13 Oct. 1954; T.B. Mitchell leg.; NCSU M.G.R. Database No. 595 • 1 ♂, T. junctus allotype; Raleigh ; Sep. 1921; T.B. Mitchell leg.; USNM U.S.N.M. 45898 /M.G.R. Database No. 590 .

DNA barcoded material

Available. BIN: BOLD:AAJ8523. Specimens examined and sequenced:

USA – Colorado • 1 ♀; Logan County; 40.4894° N, 102.7412° W; 27 Sep. 2013; M. Vandever et al. leg.; BOLD sample ID: CMNTO_127 ; CSUC • 1 ♀; W of Colorado Springs (Hwy 24), El Paso County; 38.8540° N, 104.8820° W; 3 Aug. 2007; J. Gibbs and C.S. Sheffield leg.; BOLD sample ID: CMNTO_021 ; PCYU PCYU-GS-07:1540 . – Maryland • 1 ♂; Cove Point , Calvert County; 38.3868° N, 76.3857° W; 7–8 Oct. 2007; L. Shapiro leg.; BOLD sample ID: CCDB-03761 E08 ; BIML USGS_ DRO116873 . – New Mexico • 1 ♂; 16 km NW of Tucumcari on Hwy 104; 35.2663° N, 103.8480° W; 29 Aug. 2009; C.S. Sheffield, S. Dumesh, and L. Packer leg.; BOLD sample ID: CMNTO_139 ; PCYU. – South Carolina • 1 ♀; Savannah River Site , Aiken County; 33.3758° N, 81.5278° W; 1 Oct. 2018; S. Helmreich leg.; BOLD sample ID: CMNTO_164 ; WRME SCFS005768 .

Non-barcoded material

MEXICO • 2 ♀♀; Chihuahua, 9 mi S of Hidalgo del Parral; 8 Aug. 1967; R.C. Gardner, C.R. Kovacic, and K. Lorenzen leg.; UCBME .

USA – Arizona • 1 ♀; 18 mi SW of Apache , Cochise County; 22–23 Aug. 1994; J.G. Rozen and J.S. Ascher leg.; AMNH • 1 ♀; 8 mi NE of Portal , Cochise County; 23–25 Aug. 1989; J.G. Rozen and R.L. Foster leg.; AMNH • 2 ♀♀; 8 mi S of Moons Park , Coconino County; 12 Sep. 1995; Griswold and Tepedino leg.; BBSL BBSL582183 , BBSL582214 • 1 ♀; Avra Valley ; 6 Jul. 1955; G. Butler and F. Werner leg.; UAIC. – Arkansas • 1 ♀; Eureka Springs ( Ouachita Mountains ); 6 Sep. 1939; E.C. Van Dyke leg.; CAS • 2 ♀♀; Hot Springs ; 1 Oct. 1939; E.C. Van Dyke leg.; CAS • 1 ♀; Knob Hill Rst ( Ouachita Mountains ); 1 Sep. 1939; E.C. Van Dyke leg.; CAS. – Colorado • 1 ♀; Boulder County; 6 Sep. 1926; C.H. Hicks leg.; UCMC • 1 ♀; same data as for preceding; 6 Sep. 1926; C.P. Custer leg.; UCMC • 1 ♀; Boulder , Boulder County; 21 Sep. 1932; H.W. Campbell leg.; UCMC • 1 ♀; same data as for preceding; 5 Sep. 1976; P. Robinson leg.; UCMC • 2 ♀♀; Owens Lake ( Boulder ); 8 Sep. 1932; C.H. Hicks leg.; UCMC • 1 ♀; Upper Queen Reservoir , Kiowa County; 13 Sep. 1997; D. Leatherman leg.; CSUC. – Florida • 1 ♂; St. Andrews State Park , Panama City, Bay County; 14 Oct. 2000; C. Porter and L. Stange leg.; FSCA. – Georgia • 1 ♀; Tifton ; ANSP. – Illinois • 1 ♂; 3.5 mi N of Oquawka , Henderson County; 24 Aug. 1983; E. Miliczky leg.; INHS 7843 . – Minnesota • 1 ♂ (studied from images); Altona State Wildlife Management Area , Pipestone County; 44.1928° N, 96.3214° W; “ 8/6/2019 ”; D. Drons leg.; MNDNR MNDNR180590 • 2 ♀♀; Rochester ; 30 Aug. 1956; G.E. Bohart leg.; BBSL BBSL522481 , BBSL522624 • 1 ♀ (studied from images); Zumbra Heights , Carver County; 31 Aug. 1929; E.C. Alfonsus leg.; UMSP UMSP146916 . – Mississippi • 1 ♀; West Point ; 16 Sep. 1904; F.C. Bishopp leg.; USNM M.G.R. Database No. 1373 • 2 ♂♂; same data as for preceding; 16 Sep. 1904; F.C. Bishopp leg.; USNM M.G.R. Database Nos 1371 , 1372 . – Missouri • 4 ♀♀; Branson ; 15 Sep. 1939; E.C. Van Dyke leg.; CAS • 2 ♀♀; same data as for preceding; 16 Sep. 1939; E.C. Van Dyke leg.; CAS • 1 ♀; Columbia , Boone County; 1 Sep. 1966; F.D. Parker leg.; UCBME M.G.R. Database No. 1390 • 1 ♀; same data as for preceding; 25 Sep. 1966; F.D. Parker leg.; UCBME M.G.R. Database No. 1378 . – New Mexico • 2 ♂♂; 16 km NW of Tucumcari on Hwy 104; 35.2663° N, 103.8480° W; 29 Aug. 2009; C.S. Sheffield, S. Dumesh, and L. Packer leg.; PCYU • 1 ♀; 26 mi S of Animas, Hidalgo County; 20 Aug. 1986; R.J. McGinley and B.M. Norden leg.; USNM • 1 ♀; Las Cruces; 30 Aug.; Townsend leg.; USNM • 1 ♀; same data as for preceding; Aug. ??27; Townsend leg.; USNM • 1 ♀; Las Vegas , San Miguel County; 35.6176° N, 105.2074° W; 30 Aug. 2007; J. Gibbs and C.S. Sheffield leg.; PCYU PYU-3394 • 1 ♀; St. Vrain , Curry County; 3 Oct. 1965; BBSL. – New York • 1 ♀; Long Island ; “09”; G. Salt leg.; NHMUK B.M.1931-343 • 1 ♂; Napeague ( Long Island ); 2 Jul. 1954; R. Latham leg.; USNM M.G.R. Database No. 1370 . – North Carolina • 3 ♂♂; Black Mountains; AMNH Ac. 33827/M.G.R. Database Nos 1379 to 1381 • 1 ♀; Moore County; 8 Oct. 1964; B.S. Heming leg.; DEBU debu01089134 . – Oklahoma • 1 ♂; Songbird Park ( Norman ), Cleveland County; 35.1700° N, 97.4200° W; 5 Sep. 2022; K.L.J. Hung leg.; OKBS OKBS.POL.5883 . – South Carolina • 1 ♀; Columbia ; 18 Sep. 1951; L. and G. Townes leg.; CAS M.G.R. Database No. 597 . – Tennessee • 1 ♀; Memphis ; 9 Sep. 1920; “ Ex Coll. M.A. Cazier ”; AMNH M.G.R. Database No. 1382 . – Texas • 1 ♂; El Paso , El Paso County; 11 Jul. 1917; G. Salt leg.; NHMUK • 1 ♀; Lajitas , Brewster County; 2 Oct. 1960; J.E. Gillaspy leg.; CAS .

Redescription

MEASUREMENTS OF HOLOTYPE. Body length 8.7 mm; ITW 1.9 mm; head length 2.3 mm; head width 3.3 mm; fore wing length 7.1 mm.

Both sexes

INTEGUMENT COLORATION. Dark brown to black except as follows. Mandible with apical two-fifths golden yellow. Mandible with basal three-fifths (except for extreme base); labrum to some extent (except basomedially); scape, pedicel, and F1 to some extent (entirely dark brown/black in some non-type specimens); pronotal lobe (entirely black in T. junctus holotype and paratype and multiple non-type specimens); tegula; axilla with tip (entirely black in E. lectiformis holotype, T. junctus holotype and paratype, and multiple non-type specimens); coxae to some extent; trochanters to tibiae (excluding brown meso- and metatibial spurs) partially to entirely; tarsi entirely; metasomal terga laterally (entirely dark brown/black in T. junctus holotype and paratype and multiple non-type specimens); pygidial plate to some extent; and metasomal sterna to some extent (entirely dark brown/black in some non-type specimens) orange. F2 with orange spot basally (entirely dark brown in some non-type specimens). Fore wing membrane dusky subhyaline throughout. Hind wing membrane dusky subhyaline to hyaline.

PUBESCENCE. Face with tomentum densest around antennal socket. Clypeus, upper paraocular and frontal areas, and vertexal area mostly exposed. Pronotal collar with tomentum uniformly pale yellow. Mesoscutum with well-defined paramedian band of pale-yellow tomentum; pale tomentum otherwise mostly restricted to lateral and posterior margins. Mesopleuron with off-white to pale-yellow, appressed, branched setae; upper half densely setose, except behind pronotal lobe, with setae slightly sparser on hypoepimeral area; ventrolateral half nearly bare, except along margins. Metanotum with tomentum uninterrupted, uniformly pale yellow. Propodeal triangle mostly glabrous, with (pale) setae restricted to small lateral patches. Metasomal terga with bands of pale-yellow tomentum. T1 with basal and apical transverse bands interrupted medially (former more widely than latter) (T1 with apical transverse band narrowed medially in T. junctus holotype and allotype and multiple non-type specimens) and subparallel, discal patch transversely oblong (verging on widely trapezoidal in T. rhododontus holotype). T2–T4 with apical transverse bands complete and medially somewhat removed from apical margins of terga, that of T2 with pair of basomedially convergent anterolateral extensions. S2–S3 with medially interrupted apical transverse bands of white tomentum.

SURFACE SCULPTURE. Labrum coarsely and densely (most i <1d) rugose-punctate. Clypeus densely punctate (most i <1d) but interspaces well defined, shining. Vertexal area somewhat sparsely punctate (some i>2d), especially around ocelli. Mesoscutum, mesoscutellum, and axilla with punctures more or less equally dense and nearly contiguous (most i <1d) (interspaces well defined, shining in E. lectiformis holotype, T. lusor holotype, T. junctus holotype and paratype, and multiple non-type specimens). Mesopleuron with punctures in upper half nearly contiguous and denser (i <1d) than in ventrolateral half (i≤ 2d); interspaces somewhat dull due to tessellate surface microsculpture where punctures not contiguous; punctures similar in size throughout. Discs of metasomal terga with punctures very fine, dense (i ≈ 1d), and evenly distributed; interspaces somewhat dull due to tessellate surface microsculpture.

STRUCTURE. Labrum with pair of small subapical denticles, each preceded by longitudinal carina. Pronotal collar somewhat elongate (medial length ~ 4/5 MOD). Mesoscutellum moderately bigibbous. Axilla extending well beyond midlength of mesoscutellum but not as far back as its posterior margin; tip distinctly pointed and hooked (i.e., concave along medial margin), mesally unattached to mesoscutellum for approximately half medial length of axilla; lateral margin somewhat arcuate. Fore wing with three submarginal cells.

Female

T5 with concave apical margin and large patch of pale-yellow tomentum on each side lateral to pseudopygidial area. Pseudopygidial area with underlying integument extensively orange in E. lectiformis holotype and multiple non-type specimens, with triangular region of posteriorly directed setae with three subregions (basal patch of dense, golden setae; darker subapical band of sparser, coppery brown setae; and apical row of dense, suberect, silvery setae) within larger trapezoidal space of posteromedially directed dark brown setae. Pygidial plate apically truncate. S4 with apical transverse band of white tomentum. S5 straight in lateral view, with apical fimbria of coppery bristle-like setae.

Male

Paramedian band anteriorly joined to lateral transverse band of equally dense pale-yellow tomentum along anterior margin of mesoscutum in T. rhododontus holotype, T. lusor holotype, T. junctus allotype, and multiple non-type specimens. T5–T6 with complete apical transverse bands. Pygidial plate relatively flat and apically rounded, with lateral margin somewhat sinuate. S4–S5 each with apical/subapical fringe of dense, long (> 1 MOD), curved, coppery brown setae, contrasting with apical transverse bands of white tomentum of preceding sterna.

Distribution

Eastern United States to northern Mexico ( Fig. 12K ).

Ecology

Host records

Unknown.

Floral records

Labels of examined voucher specimens indicate that this species has been collected from the following flowering plant species: in Asteraceae , Grindelia sp. or spp., Haplopappus sp. , Helenium sp. , Pityopsis graminifolia (Michx.) Nutt. , Solidago canadensis L., and S. velutina DC. ; and in Convolvulaceae , Cuscuta cuspidata Engelm. and C. indecora Choisy.

Remarks

In the original description of Epeolus lectiformis, Cockerell (1925a) did not mention T. rhododontus , having misidentified the two female representatives as an Epeolus , and stated that “[f]rom Cresson’s description [he] should hesitate to separate this [species] from E. lectus [ Cresson, 1878]”; however, he opted to describe it as a separate species because in E. lectus the spurs are not black and the metasoma exhibits features that are quite distinctive. In the same publication, Cockerell (1925a) also described T. lusor , comparing the (male) holotype with T. schwarzi Cockerell, 1921 , T. cressonii (Robertson, 1897) , and T. pectoralis , all of which are visibly different bees and none of which belong to the simplex species group. Curiously, he did not compare the specimen to the holotype of T. rhododontus , to which it is most similar.

Based on specimens from the Eastern United States, Mitchell (1962) described this species under the name T. junctus . Neither T. rhododontus , E. lectiformis , nor T. lusor , whose type localities are all in Colorado, were mentioned in the original description of T. junctus . Except for its slightly larger size, the (female) holotype of T. junctus looks very much like that of E. lectiformis , and in both specimens the axillae are entirely black whereas in the (male) holotypes of T. rhododontus and T. lusor the axillae are to some extent reddish orange (more so in that of T. rhododontus ). Barcode sequences of specimens with entirely black axillae (from Maryland and South Carolina) and axillae with reddish tips (from Colorado and New Mexico) were assigned the same BIN, exhibiting 99.2–100.0% similarity.

As there are no discernable morphological differences among the holotypes of T. rhododontus , E. lectiformis , T. lusor , and T. junctus that fall outside the range of variation observed among both barcoded and non-barcoded specimens, E. lectiformis , T. lusor , and T. junctus are herein synonymized under T. rhododontus .

Romankova (2004) reported T. junctus from Ontario and Canada based on a single male specimen deposited in the CNC, which was examined by the first author of the present study and determined to have been misidentified. The specimen (CNC 428319) is undoubtedly E. pusillus Cresson, 1864 , and no actual representatives of T. rhododontus from Canada are known at this time.

Figures

Fig. 9. Right pro- and mesotrochanters of male (anterior facing right). A. Triepeolus tuberculifer Onuferko, Rightmyer & Roig-Alsina, 2024, allotype (FSCA M.G.R. Database No. 3704), showing distinct protuberances (blue arrows). B. T. obliteratus Graenicher, 1911 (WRME WRME_EJH02370). C. T. oblongimacula sp. nov., allotype (BOLD sample ID: CMNTO_298; PCYU PCYU-SD09:28). D. T. rhododontus Cockerell, 1921 (BOLD sample ID: CMNTO_139; PCYU).

Fig. 12A–D (continued on next page). Distribution maps. A. All species in the Triepeolus simplex group. B. T. apache sp. nov. C. T. eumeniformis sp. nov. D. T. hirsutus sp. nov. Approximate geographic ranges are indicated in orange and were estimated from occurrence records known to the authors (yellow and blue circles, with the latter indicating localities of DNA barcoded specimens).

Fig. 26. Triepeolus rhododontus Cockerell, 1921. A. Epeolus lectiformis Cockerell, 1925 paratype, ♀ (CAS M.G.R. Database No. 1438) (herein synonymized under T. rhododontus), habitus, lateral view. B. Female (BOLD sample ID: CMNTO_164; WRME SCFS005768), habitus, dorsal view. C. Male (PCYU), habitus, lateral view. D. Female (AMNH) pseudopygidial area, dorsal view.

Fig. 15. T1 of female, dorsal view. A. Triepeolus apache sp. nov., paratype (AMNH). B. T. hirsutus sp. nov., paratype (AMNH). C. T. oblongimacula sp. nov., paratype (AMNH). D. T. rhododontus Cockerell, 1921 (AMNH). E. T. segregatus (Cockerell, 1900) (PCYU). F. T. shoshone sp. nov., paratype (PCYU PCYU-GS-07:2171).