Trissolcus eriventus Le, 1893

Talamas, Elijah J., Buffington, Matthew L. & Hoelmer, Kim, 2017, Revision of Palearctic Trissolcus Ashmead (Hymenoptera, Scelionidae), Journal of Hymenoptera Research 56, pp. 3-185 : 26-30

Trissolcus eriventus Le Figures 59 , 60-62

Trissolcus eriventus Lê, 1997: 23, 25 (original description, keyed); Lê, 2000: 312, 315 (description, keyed, type information).

Description.

Female body length: 1.15-1.17 mm (n=5). 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, becoming brown distally. Color of A7-A11 in female: brown. Number of basiconic sensilla on A6: 0. Number of basiconic sensilla on A7: 2. Facial striae: present as short grooves. Number of clypeal setae: 4. Microsculpture on gena directly above mandibular condyle: present. Shape of ventral gena in lateral view: narrow. Genal carina: present and extending dorsally to vicinity of lower margin eye. Malar striae: absent. Sculpture of malar sulcus: antero-posteriorly striate. Orbital furrow: medially delimited by ridge or carina at midpoint of eye, poorly defined or absent near intersection with malar sulcus. Macrosculpture of frons between antennal scrobe and anterior ocellus: absent. Preocellar pit: present. Setation of lateral frons: dense. Punctation of lateral frons: present along medial margin of orbital furrow. Sculpture directly ventral to preocellar pit: microsculptured. Macrosculpture of lateral frons: absent. OOL: separated by less than one ocellar diameter. Hyperoccipital carina: uncertain, present only posterior to lateral ocellus; uncertain, absent; uncertain, effaced medially. Macrosculpture of posterior vertex: absent. Microsculpture on posterior vertex along occipital carina: present. Anterior margin of occipital carina: coarsely crenulate.

Epomial carina: present. Macrosculpture of lateral pronotum directly anterior to netrion: finely rugulose. Netrion sulcus: complete. Pronotal suprahumeral sulcus in posterior half of pronotum: undifferentiated from sculpture of dorsal pronotum; weakly differentiated from sculpture of dorsal pronotum. Location of pronotal suprahumeral sulcus: posterior half of pronotum.

Mesosoma. Number of episternal foveae: 3; 2. Course of episternal foveae ventrally: abutting postacetabular sulcus. Course of episternal foveae dorsally: extending to mesopleural pit. Subacropleural sulcus: present. Speculum: transversely strigose. Mesopleural pit: simple. Mesopleural carina: complete. Sculpture of femoral depression: rugulose and pustulate along ventral half of mesopleural carina. Patch of striae at posteroventral end of femoral depression: uncertain, absent. Setal patch at posteroventral end of femoral depression: absent. Microsculpture of anteroventral mesopleuron: present dorsally. Macrosculpture of anteroventral mesopleuron: irregularly rugulose. Postacetabular sulcus: formed by open crenulae. Mesopleural epicoxal sulcus: formed by open crenulae. Mesofurcal pit: absent. Setation of posteroventral metapleuron: absent. Sculpture of dorsal metapleural area: rugose. Posterodorsal metapleural sulcus: poorly defined to absent. Paracoxal sulcus in ventral half of metapleuron: indistinguishable from sculpture to 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: absent. 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: present. Notaulus: extending at least 1/3 length of mesoscutum. Median protuberance on anterior margin of mesoscutellum: uncertain, absent; uncertain, present. Protruberance on anterior margin of mesoscutellum directly posterior to notaulus: absent; 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: punctures visible in at least ventral half, not quite striate. Macrosculpture of mesoscutellum: absent. Microsculpture on mesoscutellum: present throughout. Setation of posterior scutellar sulcus: present. Form of metascutellum: coarsely rugose. Metanotal trough: foveate, foveae occupying more than half of metanotal height. 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): 2; 1. Setation of laterotergite 1: absent. Longitudinal stria tion of T2: present throughout anterior half of tergite. 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 in anterior half of sternite not covered by laterotergites. Setation of S2: sparsely present throughout area not covered by laterotergite.

Diagnosis.

Trissolcus eriventus is a straightforward species to identify; the rugosity of the orbital furrow (Figure 61 ) is known to us only from this species.

Link to distribution map.

http://hol.osu.edu/map-large.html?id=154380

Material examined.

Holotype, female: VIETNAM: Hanoi Prov., Nghia Do , Hanoi, 19.VIII.1982, IEBR 0046 (deposited in IEBR) . Other material: CHINA: 5 females, USNMENT00916344, 00916457-00916460 ( BMNH) .

Comments.

The hyperoccipital carina in this species is highly variable, ranging from complete to essentially absent between the posterior ocelli. This level of variability is unusual given the stability of this character in other species of Trissolcus .

Figures

Figure 59. Trissolcus eriventus female (USNMENT 00916459), head, mesosoma, metasoma, lateral view. Scale bars in millimeters.

Figures 60 - 62. Trissolcus eriventus 60 female (USNMENT 00916458), head, mesosoma, metasoma, dorsal view 61 female (USNMENT 00916457) 62 female (USNMENT 00916458). Scale bars in millimeters.