Trissolcus edessae Fouts, 1920

Talamas, Elijah J., Buffington, Matthew L. & Hoelmer, Kim, 2017, Revision of Palearctic Trissolcus Ashmead (Hymenoptera, Scelionidae), Journal of Hymenoptera Research 56, pp. 3-185 : 19-22

Trissolcus edessae Fouts Figures 46-47 , 48-51

Trissolcus edessae Fouts, 1920: 65 (original description); Masner & Muesebeck, 1968: 72 (type information); Johnson, 1984a: 799, 801 (description, keyed); Johnson, 1987: 289, 300 (diagnosis, keyed); Johnson, 1992: 626 (cataloged, type information); Talamas, Johnson & Buffington, 2015: 56, 74 (diagnosis, keyed, type information).

Description.

Female body length: 1.27-1.67 mm (n=31). Male body length: 1.18-1.70 mm (n=8). Body color: head, mesosoma, and metasoma black.

Head. Color of radicle: yellow. Length of radicle: less than width of clypeus. Color of A1-A6 in female: yellow. Color of A7-A11 in female: brown. Number of basiconic sensilla on A6: 0. Number of basiconic sensilla on A7: 2. Facial striae: absent. Number of clypeal setae: 2. Microsculpture on gena directly above mandibular condyle: present. Shape of ventral gena in lateral view: narrow. Genal carina: absent. Malar striae: absent. Sculpture of malar sulcus: faintly rugulose. Orbital furrow: expanding in size ventrally, strongly so at intersection with malar sulcus. Macrosculpture of frons between antennal scrobe and anterior ocellus: transversely strigose ventrally, absent dorsally. Preocellar pit: present. Setation of lateral frons: moderately dense. Punctation of lateral frons: sparse. Sculpture directly ventral to preocellar pit: microsculptured. Macrosculpture of lateral frons: absent. OOL: separated by less than one ocellar diameter. Hyperoccipital carina: complete. Macrosculpture of posterior vertex: absent. Anterior margin of occipital carina: coarsely crenulate.

Mesosoma. Epomial carina: present. Macrosculpture of lateral pronotum directly anterior to netrion: rugose. Netrion sulcus: incomplete. Pronotal suprahumeral sulcus in posterior half of pronotum: weakly differentiated from sculpture of dorsal pronotum. Number of episternal foveae: 4 or more. Course of episternal foveae ventrally: abutting postacetabular sulcus. Course of episternal foveae dorsally: distinctly separate from mesopleural pit. Subacropleural sulcus: present. Speculum: transversely strigose. Mesopleural pit: extending ventrally into dorsoventral furrow parallel to mesopleural carina. Mesopleural carina: well defined anteriorly, poorly defined to absent posteriorly. Sculpture of femoral depression: dorsoventrally strigose in dorsal half. Patch of striae at posteroventral end of femoral depression: absent. Setal patch at posteroventral end of femoral depression: present. Microsculpture of anteroventral mesopleuron: present throughout. Macrosculpture of anteroventral mesopleuron: absent. Postacetabular sulcus: formed by open crenulae. Mesopleural epicoxal sulcus: formed by open crenulae. Setation of posteroventral metapleuron: absent. Sculpture of dorsal metapleural area: smooth area small because cells of surrounding sulci are large. Posterodorsal metapleural sulcus: poorly defined to absent. Paracoxal sulcus in ventral half of metapleuron: indistinguishable from sculpture to absent; absent. Anteroventral extension of metapleuron: extending to base of mesocoxa. Metapleural epicoxal sulcus: present as coarse rugae. Mesoscutal humeral sulcus: indicated by a line of cells. Median mesoscutal carina: present. Macrosculpture of mesoscutum: absent. Pattern of mesoscutal microsculpture: uniform throughout. Mesoscutal suprahumeral sulcus: comprised of cells. Length of mesoscutal suprahumeral sulcus: about half the length of anterolateral edge of mesoscutum. Parapsidal line: absent. Notaulus: extending at least 1/3 length of mesoscutum. Median protuberance on anterior margin of mesoscutellum: present. Protruberance on anterior margin of mesoscutellum directly posterior to notaulus: present. Shape of dorsal margin of anterior lobe of axillar crescent: round. Sculpture of anterior lobe of axillar crescent: dorsoventrally strigose. Area bounded by axillar crescent: striate. Macrosculpture of mesoscutellum: absent. Microsculpture on mesoscutellum: present throughout. Median mesoscutellar carina: absent. Setation of posterior scutellar sulcus: present. Form of metascutellum: coarsely rugose. Metanotal trough: smooth in dorsal half, with line of foveae ventrally. Metapostnotum: invaginated near lateral edge of metascutellum. Length of postmarginal vein: about twice as long as stigmal vein. Color of legs: coxae brown, legs elsewhere yellow. Anteromedial portion of metasomal depression: punctate or crenulate.

Metasoma. Longitudinal striae on T1 posterior to basal costae: present. Number of sublateral setae (on one side): 0. Setation of laterotergite 1: absent. Longitudinal striation of T2: absent. Setation of T2: present in a transverse line posteriorly. Setation of laterotergite 2: present. Posteriorly directed setae on medial S1: present. Striation of S2: present laterally, absent medially. Setation of S2: present posteromedially.

Diagnosis.

Trissolcus edessae is unique among the species of the flavipes group treated here in that it has a medial mesoscutal carina. It bears no particular affinity to other Palearctic species in the flavipes group, but is morphologically similar to two species in the Nearctic: T. brochymenae and T. euschisti , from which it may be separated by the distinctly bicolored antennae, with A1-A6 yellow, and A7-A11 brown (Figures 46 , 47 ). The labrum of T. edessae has a pair of distinct pits that are easily visible with light microscopy (Figure 50 ), whereas these pits in other species typically require scanning electron microscopy for observation. This character has yet to be fully explored throughout the genus because the labrum is often occluded, but we suspect that it will be informative.

Link to distribution map.

http://hol.osu.edu/map-large.html?id=3221

Material examined.

Holotype, female: UNITED STATES: LA, Orleans Parish , New Orleans, 23.VII.1919, C. E. Smith, USNMENT00872412 (deposited in USNM) . Other material: SPAIN: 1 female, USNMENT00916178 (BMNH). (37 females, 3 males, 6 unsexed) EL SALVADOR: 5 unsexed, USNMENT00989220-00989221 (CNCI); USNMENT00764980-00764981, 00764993 (USNM) . UNITED STATES: 36 females, 3 males, USNMENT00954346-00954377, 00954384-00954390 (USNM) .

Comments.

The specimen illustrated in Figures 46 - 51 is the only known representative of T. edessae outside of the Nearctic. We compared this specimen directly to the type of T. edessae and found nothing to suggest that it is a different species. The collecting locality of Valencia, Spain, is noteworthy given the large volume of shipping traffic that passes through this port city and we consider it likely that T. edessae was delivered to Valencia on cargo. Determination of whether or not it became established in Europe will require focused sampling, as even in the Nearctic it is not a very common species. This phenonenon of species spreading around the world, as is the case with T. edessae and T. japonicus (Talamas et al. 2015), emphasizes the importance of a cosmopolitan perspective when conducting alpha taxonomy.

Figures

Figures 46 - 47. Trissolcus edessae, female (USNMENT 00916178) 46 head, mesosoma, metasoma, lateral view 47 head, mesosoma, metasoma, dorsal view. Scale bars in millimeters.

Figures 48 - 51. Trissolcus edessae, female (USNMENT 00916178) 48 head and mesosoma, anterolateral view 49 head, anterior view 50 head and mesosoma, ventrolateral view 51 mesosoma, dorsal view. Scale bars in millimeters.