Gatesina Pujade-Villar, Cuesta-Porta & Hanson, 2018

Cuesta-Porta, Víctor, Caicedo, Guadalupe, Hanson, Paul & Pujade-Villar, Juli, 2018, Gatesina colombiana n. gen. & n. sp. (Hymenoptera: Chalcidoidea, Eurytomidae), new Rileyinae associated with Myrcianthes (Myrtaceae) from Colombia, Zootaxa 4471 (1), pp. 111-124 : 114-115

Gatesina Pujade-Villar, Cuesta-Porta & Hanson n. gen.

Type species. Gatesina colombiana n. sp., monotypic.

Diagnosis. Females of Gatesina differ from those of other genera of Rileyinae in the morphology of the metasoma, which is laterally compressed, with the posterior part bent dorsally upwards, and with gastral tergites 6‒8 and the ovipositor perpendicular to the longitudinal axis of the body ( Figs 17, 19, 20 ). Other Rileyinae usually do not have the metasoma bent like this and never to such an extent. Five other characteristics different from most other Rileyinae ( Lotfalizadeh 2007; Gates 2008; Caicedo & Pujade-Villar 2017) are: (i) epicnemium with smooth ovate depression with sparse long setae and bordered by a faint carina ( Fig. 12 ) (other Rileyinae usually have longitudinal glabrous sulci, but never this structure); (ii) prosternum with mesal, laminate and setose projection on ventral side ( Fig. 12 ); (iii) distance between toruli less than their diameter ( Figs 1, 2 ) (in other Rileyinae the distance between toruli is usually greater than their diameter, except some Rileya Ashmead 1888); (iv) postgenal bridge slightly concave and not carinately margined ( Figs 4, 5 ) (usually delimited by a strong depression or carina in other Rileyinae ); (v) propodeal spiracles round (in other Rileyinae usually elongate and transversely or obliquely oriented). The new genus is morphologically similar to Neorileya Ashmead 1904 , but differs, in besides the aforementioned characters, the following four features: (i) clypeus with 6 sparse setae that surpass the ventral clypeal margin and without a carina reaching intertorular space ( Figs 1‒3 ) (glabrous in Neorileya except for two setae on each lateral margin of clypeus and with medial carina reaching intertorular space), (ii) frons finely strigose ( Figs. 1, 2 ) (coarsely reticulate to umbilicate in Neorileya ), (iii) lower margin of eye midway between toruli and clypeus ( Figs 1, 2 ) (nearly at clypeal level in Neorileya ), and (iv) with a faint, oblique carina connecting metacoxa and nucha, but transverse carina connecting metacoxae absent ( Fig. 10 ) ( Neorileya with oblique metacoxal-nuchal carina absent, but inter-metacoxal transverse carina present). Moreover, a mesepimeral-metapleural junction is present, with a tongue visible but not overlapping the metapleuron ( Fig. 13 ) (absent from Neorileya ; present in Platyrileya Burks 1971 and Rileya, but tongue overlapping metapleuron in Rileya).

Etymology. This genus is named in honor of Michael W. Gates (Smithsonian Institution, Washington, USA) for all his work and contribution to hymenopteran research, especially to the Rileyinae and the family Eurytomidae as a whole.

Gender. Feminine.

Biology. Parasitoid of gall-inducing Eurytominae in Myrcianthes ( Myrtaceae ) fruits. Two possible hosts known so far: Sycophila n. sp. and Eurytoma n. sp. Both phytophagous species attack on Myrcianthes fruits and can coexist in the same gall. Eurytoma larvae chamber substitutes the fruit’s seeds. Sycophila larvae chamber is placed in the hyperplasic mesocarp near the limit with exocarp. Gatesina has always been found in external chambers similar to Sycophila . Caicedo & Pujade-Villar (2017) also found correlation between Sycophila and Gatesina emergence of the adults. Sycophila is very likely to be parasitized by Gatesina, but Eurytoma or other hosts are not discarded.

Distribution. Colombia.

Figures

FIGURES 13–22. Gatesina colombiana. 13: mesosoma, mesepimeral-metapleural junction (female); 14, 15: propodeum, posterior view (14, female; 15, male); 17, 18: metasoma (17, female; 18, male); 19, 20: female, coloration and wing venation (19, lateral view; 20, dorsal view); 21, 22: male, coloration and wing venation (21, lateral view; 22, dorsal view).

FIGURES 1–12. Gatesina colombiana. 1, 2: head, frontal view (1, female; 2, male); 3: clypeus detail (female); 4, 5: head, posterior view (4, female; 5, male); 6–8: antennae (6, female; 7, female scape; 8, male scape and pedicel); 9–12: female mesosoma (9, dorsal view; 10, ventral view; 11, lateral view; 12, epicnemium in frontal view).