Triepeolus matildae Rightmyer

Rightmyer, Molly G., Kono, Yoshiaki, Kohn, Joshua R. & Hung, Keng-Lou James, 2014, A new species of Triepeolus (Hymenoptera: Apidae), with comments on T. utahensis (Cockerell) and T. melanarius Rightmyer, Zootaxa 3872 (1) : -

Triepeolus matildae Rightmyer new species

( Figs. 1–3 , 5, 6 ; Rightmyer 2008: 70–71; Figs. 90, 91)

Diagnosis. This species is extremely similar to the more widely distributed T. utahensis due to the unusual form of the pseudopygidial area in females (i.e., with relatively long setae that are parted medially, Fig. 3 ), but can be separated from that species based on the following characters: Females of T. matildae have a pseudopygidial area with setae that are slightly shorter, more reddish, and cover a smaller area of the pseudopygidial area than that of T. utahensis ; in T. matildae , the long, laterally directed setae make up an area about 1.0 OD x 1.0 OD on either side of the pseudopygidial area ( Fig. 3 , area in triangle), while in T. utahensis , the long, laterally directed setae make up an area nearly 2.0 OD x 2.0 OD (Fig. 4, area in triangle; also compare Figs 91 and 89 in Rightmyer 2008); and in T. matildae the labrum, legs (excluding basal coxae), pronotal lobe, tegula, and sometimes the underlying integument of the metasoma are mostly orange to red or brown ( Fig. 1 , but see Comments, below) rather than mostly black in T. utahensis ( Rightmyer 2008: Fig. 88). Males of T. matildae can be differentiated from T. utahensis by the slightly broader and more reddish pygidial plate ( Fig. 6 ; narrower and black in T. utahensis , Fig. 8); the entirely pale apical fringes on S4–S5 ( Fig. 5 ; brown to black in T. utahensis , Fig. 7, sometimes with slight pale tinge on S4); and by the reddish-orange integumental color patterns also found in females (males of T. matildae with additional black areas of integument especially on the femora). Males of T. melanarius are also similar to T. matildae and especially T. utahensis due to their overall size and banding pattern; however, in T. melanarius the venter of the metasoma is entirely black (Fig. 9; S2–S3 with white setae in T. utahensis , Fig. 7; and S2–S5 with white setae in T. matildae , Fig. 5 ). The pygidial plate of T. melanarius (Fig. 10) is similar to that of T. utahensis (Fig. 8).

Triepeolus matildae keys to T. utahensis (as T. heterurus ) in the Key to females of North and Central America ( Rightmyer 2008: 11), but can be separated from that species based on the diagnostic characters given above.

Description. Length ca. 7–9 mm; ITW 1.4–1.9 mm. Integument black, with red to orange on mandible (apical half only in male), labrum, apical margin of clypeus (entirely black in male), scape, pedicel, F1, basal F2 (antenna black in male), pronotal lobe, tegula, legs excluding basal coxae (black areas found on trochanters, femora, and tibiae in male), beneath hairs of pseudopygidial area in some specimens, and venter of metasoma in part or entirely; dorsally with bands of setae yellow to pale yellow. Clypeus lacking midline, with very weak larger punctures, often covered with diffuse to dense, pale setae. Mesepisternum with dorsal half and anterior margin covered with pale yellow, suberect to erect branched setae, and sparse, erect, simple setae; ventrally with more or less well-defined spot of diffuse or dense, brown, branched setae and nearly contiguous punctures (females), or covered with erect to suberect, dense, white, branched setae (males). Paramedian bands distinct. Scutellum with dorsal biconvexities weakly pronounced; axillar spines triangular, reaching or not reaching midpoint of scutellum. T1 interspace subovate; T2 with lateral, longitudinal band of pale setae forming acute angle with apical, transverse band of pale setae. Female: Pseudopygidial area with setae parted medially and directed laterally to posterolaterally at approximately 45 degree angle, apical margin straight; S5 not downcurved. Male: Pygidial plate moderately narrow and long, lacking or with extremely vague transverse basal ridge; S2–S3 with apical bands of white setae (S3 with white setae slightly extended past apical margin); S4–S5 with white to golden apical fringes.

Comments. One female specimen, listed in Additional Material below, has a slightly different color pattern from other T. matildae examined: the orange to reddish integument is restricted to the mandible, labrum, portions of the scape, pedicel, F1, tarsi, and portions of the metasomal sterna. The tegula is reddish brown and the pronotal lobe is dark brown. The hairs of the pseudopygidial area are as described above for T. matildae . As the specimen is nearly 80 years old, it is unclear how much of the color variation is due to preservation or true variation in the species’ integumental color pattern. Timberlake gave this specimen a manuscript name noting the reddish color of the tarsi; he gave a separate manuscript name to the paratype specimen collected at the same locality honoring Linsley.

Distribution. MEXICO: Baja California; USA: California

Floral Records. Deinandra fasciculata Greene (Asteraceae) , Eriogonum fasciculatum Benth. (Polygonaceae) , Gutierrezia Lag. sp. ( Asteraceae ), Hemizonia DC. ( Asteraceae ) (sic, possibly Deinandra fasciculata ?)

Seasonal Records. 14 May to 22 September.

Holotype. " USA: CA: San Diego Co. San Diego, N32.8423, W117.0662 Jul 9, 2012 Aerial net Coll. KJ Hung #15419 ex. Gutierrezia sp. // HOLOTYPE ♀ Triepeolus matildae Rightmyer " ( AMNH)

Paratypes. MEXICO: BAJA CALIFORNIA: Ensenada, Inland from San Quintín, 25 May 1955, F. X. Williams (1♀ CAS); USA: CALIFORNIA: Los Angeles Co., Glendora, Angeles National Forest, 15 July 1944, Hemizonia field (1♀ INHS), Westwood Hills, 3 August 1935, E. G. Linsley (1♀ EMEC); San Diego Co., San Diego, N32.8892, W117.0965, 28 May 2012, Deinandra fasciculata, K. J. Hung , #13122 (1♂ SDMC), Mission Trails Regional Park, N32.8352, W117.0769, 18 May 2012, K. J. Hung, #12893 (1♀ SDMC); Spring Valley, N32.7339, W116.9506, 14 May 2013, Eriogonum fasciculatum, K. J. Hung , #21460 (1♀ UCRC), 1 June 2011, K. J. Hung, #3126 (1♂ UCRC).

Additional material. USA: CALIFORNIA: Los Angeles Co., Westwood Hills, 22 September 1935, E. G. Linsley (1♀ EMEC)

Etymology. This species is named in honor of MGR's daughter, Matilda G. Y. Gee.

Figures

FIGURES 1 – 3. Triepeolus matildae, sp. nov. 1. Dorsal habitus of holotype. 2. Dorsal habitus of male paratype. 3. Pseudopygidial area of holotype. 4. Triepeolus utahensis, pseudopygidial area, female from San Diego.

FIGURES 5 – 6. Triepeolus matildae, sp. nov., male paratype. 5. Ventral metasoma. 6. Pygidial plate. Figures 7 – 8. Triepeolus utahensis, male, from San Diego. 7. Ventral metasoma. 8. Pygidial plate. Figures 9 – 10. Triepeolus melanarius, male, from San Diego. 9. Ventral metasoma. 10. Pygidial plate.