Genus diagnosis. Propodeum with a complete transverse carina that forks around spiracles and reaches the lateral margin of propodeum, where it intersects a raised lateral carina. Fore wing without areolet (veins r-m and 3RS absent). First mediotergite with a sharp median groove on the basal half. The only other genera of Neotropical microgastrines with a complete transverse carina on the propodeum, Clarkinella and Prasmodon, both lack a medial groove on the first mediotergite and have an areolet in the forewing (a small areolet in Clarkinella, a large and quadrangular one in Prasmodon). Mariapanteles resembles Pseudapanteles in fore wing venation, shape of mediotergites 1 and 2, and general appearance of the body. However, Pseudapanteles has an elongate, bifurcate glossa, lacks a complete transverse carina on the propodeum, and the hypopygium has a large translucent fold with many pleats; the glossa of Mariapanteles is not bifurcate and the hypopygium has a median translucent fold with no or only a few pleats visible.
Description. Body length 2.4–2.6 mm, fore wing length 2.6–2.9 mm, antenna about the same length as body. Pronotum with two lateral grooves present, the lower one excavated. Mesoscutum more or less uniformly sculptured by impressed punctures. Mesoscutum 1.3–1.4× wider than long. Mesoscutum and scutellum uniformly covered by dense, pale yellowish pilosity. Scutellum length/width at base 1.0-1.1X. Scutellar suture broad, with 4–8 costulae. Posterior band of scutellum polished. Scutellar lateral face with the polished area thin (15–25% the face height) and about half the face width. Mesopleuron mostly smooth and glabrous, except for punctures on the anterior margin and setae on all margins. Metapleuron mostly smooth, with some punctures and setae in the apical half; metapleuron with a crenulate, longitudinal sulcus running from lower margin near metacoxa through spiracle. Metapleural carina raised, with a short lamella. Propodeum mostly smooth; median carina well defined and raised its entire length, and with a clearly complete transverse carina that reaches the spiracles and forks around them (there may also be additional, shorter transverse carinae, some of them radiating from the median carina but not reaching the spiracles). Transverse carina on propodeum delimiting two areas, the anterior, basal one being more or less horizontal; the posterior, apical one is declivous. Mediotergite 1 mostly smooth and with a deep medial groove on its basal half; slightly widening for the first quarter of its length, then narrowing towards apex. Mediotergite 2 mostly smooth, transverse, subtriangular to trapezoidal in shape. Mediotergite 3 and following, unsculptured, polished and with sparse setae. Hypopygium mostly inflexible but with a medial, translucent fold ventrally where none or few (1–2) pleats are distinguishable. Ovipositor sheaths fully setose, 0.7× as long as metatibia length. Metacoxa long, surpassing the length of the third metasomal tergite. Metatibial inner spur longer than outer spur, and about half the length of metatarsomere 1. Metafemur more than 3.0× as long as wide. Fore wing without an areolet, vein R1a longer than stigma length, and vein r and 2RS evenly curved to very slightly arched (with no clear limits between the two veins). Hind wing with edge of vannal lobe medially straight to slightly concave and with uniformly distributed setae that are shorter than those at base and apex of the lobe.
Distribution. The genus occurs in Central and South American rain forests. We describe two new species, one from Costa Rica (ACG, from rain forest at 400m) and one from Brazil (Mato Grosso and Goiás; the localities are presumed to have been rain forests at the time the specimens were collected). The CNC collection contains two additional specimens from other areas of Brazil that may represent additional species, but because they are singletons we do not describe them here. It is likely that more species of this new genus will be found in Neotropical rain forests.
Biology. Unknown. All specimens have been collected with Townes-type Malaise traps.
Comments. Mariapanteles is closely related to Pseudapanteles, and future revisions of the phylogeny of Microgastrinae might find that its erection renders Pseudapanteles paraphyletic. For example, and according to Mason (1981), some species of Pseudapanteles could have a multiple or indefinite transverse carina, in which case the complete transverse carina in Mariapanteles might be seen as the extreme in a continuum from having no transverse carina to having the complete transverse carina of Mariapanteles. However, we consider that the presence of a complete transverse carina on the propodeum, forking around the propodeal spiracles, may be a strong autapomorphy that defines Mariapanteles. There are only four other genera of Microgastrinae with a similar, complete transverse carina on the propodeum: Beyarslania, Clarkinella, Neoclarkinella, and Prasmodon. However, they all appear to be only distantly related to Mariapanteles because they all lack a sharp median groove on mediotergite 1 and/or have an areolet in the fore wing.
The described species of Pseudapanteles never have a complete transverse carina. Most of the specimens in collections just have a simple median carina, with only few species having irregular transverse striations arising along the length of the median carina (but even in those cases they never reach the spiracle and never form a fork around them). One example can be seen in the original description and pictures of the species Pseudapanteles gouleti Fernández-Triana, from Canada (Figure 18, page 24, in Fernández-Triana 2010). However, the carination pattern is not comparable to a complete transverse carina – as displayed by Mariapanteles.
The presence of a bifurcate glossa is a strong autapomorphy for Pseudapanteles (it is only present in three other distantly related Microgastrinae genera: Napamus, Promicrogaster and Sendaphne). Furthermore, the differences between Mariapanteles and Pseudapanteles with respect to the pleated area of the hypopygium are also consistent in the separation of these two genera.
Currently Pseudapanteles has nine described species (Yu et al. 2009), and a wide distribution within the New World, ranging from Canada to South America (one of the species has also been introduced to Hawaii (Coulson 1992)). The actual number of species is much higher, and we have seen in collections several dozen undescribed species, mostly from the Neotropics. The vast majority of those specimens are remarkably invariant in having a bifurcate glossa and in lacking a transverse carina on the propodeum.
For all of the above reasons along with the molecular results, we have decided that Mariapanteles is a distinct, separate genus that may be closely related to Pseudapanteles.
As for the former records of Neotropical species of the genus Beyarslania (at that time called Xenogaster) (Whitfield 1997; Campos 2001), these are based on confusion with specimens of what we have described here as Mariapanteles. Based on the available evidence, we now consider Beyarslania to be restricted to the African tropics. The Neotropical specimens thought to belong to that genus should be identified as Mariapanteles.
Genus diagnosis. Propodeum with a complete transverse carina that forks around spiracles and reaches the lateral margin of propodeum, where it intersects a raised lateral carina. Fore wing without areolet (veins r-m and 3RS absent). First mediotergite with a sharp median groove on the basal half. The only other genera of Neotropical microgastrines with a complete transverse carina on the propodeum, Clarkinella and Prasmodon, both lack a medial groove on the first mediotergite and have an areolet in the forewing (a small areolet in Clarkinella, a large and quadrangular one in Prasmodon). Mariapanteles resembles Pseudapanteles in fore wing venation, shape of mediotergites 1 and 2, and general appearance of the body. However, Pseudapanteles has an elongate, bifurcate glossa, lacks a complete transverse carina on the propodeum, and the hypopygium has a large translucent fold with many pleats; the glossa of Mariapanteles is not bifurcate and the hypopygium has a median translucent fold with no or only a few pleats visible.
Description. Body length 2.4–2.6 mm, fore wing length 2.6–2.9 mm, antenna about the same length as body. Pronotum with two lateral grooves present, the lower one excavated. Mesoscutum more or less uniformly sculptured by impressed punctures. Mesoscutum 1.3–1.4× wider than long. Mesoscutum and scutellum uniformly covered by dense, pale yellowish pilosity. Scutellum length/width at base 1.0-1.1X. Scutellar suture broad, with 4–8 costulae. Posterior band of scutellum polished. Scutellar lateral face with the polished area thin (15–25% the face height) and about half the face width. Mesopleuron mostly smooth and glabrous, except for punctures on the anterior margin and setae on all margins. Metapleuron mostly smooth, with some punctures and setae in the apical half; metapleuron with a crenulate, longitudinal sulcus running from lower margin near metacoxa through spiracle. Metapleural carina raised, with a short lamella. Propodeum mostly smooth; median carina well defined and raised its entire length, and with a clearly complete transverse carina that reaches the spiracles and forks around them (there may also be additional, shorter transverse carinae, some of them radiating from the median carina but not reaching the spiracles). Transverse carina on propodeum delimiting two areas, the anterior, basal one being more or less horizontal; the posterior, apical one is declivous. Mediotergite 1 mostly smooth and with a deep medial groove on its basal half; slightly widening for the first quarter of its length, then narrowing towards apex. Mediotergite 2 mostly smooth, transverse, subtriangular to trapezoidal in shape. Mediotergite 3 and following, unsculptured, polished and with sparse setae. Hypopygium mostly inflexible but with a medial, translucent fold ventrally where none or few (1–2) pleats are distinguishable. Ovipositor sheaths fully setose, 0.7× as long as metatibia length. Metacoxa long, surpassing the length of the third metasomal tergite. Metatibial inner spur longer than outer spur, and about half the length of metatarsomere 1. Metafemur more than 3.0× as long as wide. Fore wing without an areolet, vein R1a longer than stigma length, and vein r and 2RS evenly curved to very slightly arched (with no clear limits between the two veins). Hind wing with edge of vannal lobe medially straight to slightly concave and with uniformly distributed setae that are shorter than those at base and apex of the lobe.
Distribution. The genus occurs in Central and South American rain forests. We describe two new species, one from Costa Rica (ACG, from rain forest at 400m) and one from Brazil (Mato Grosso and Goiás; the localities are presumed to have been rain forests at the time the specimens were collected). The CNC collection contains two additional specimens from other areas of Brazil that may represent additional species, but because they are singletons we do not describe them here. It is likely that more species of this new genus will be found in Neotropical rain forests.
Biology. Unknown. All specimens have been collected with Townes-type Malaise traps.
Comments. Mariapanteles is closely related to Pseudapanteles, and future revisions of the phylogeny of Microgastrinae might find that its erection renders Pseudapanteles paraphyletic. For example, and according to Mason (1981), some species of Pseudapanteles could have a multiple or indefinite transverse carina, in which case the complete transverse carina in Mariapanteles might be seen as the extreme in a continuum from having no transverse carina to having the complete transverse carina of Mariapanteles. However, we consider that the presence of a complete transverse carina on the propodeum, forking around the propodeal spiracles, may be a strong autapomorphy that defines Mariapanteles. There are only four other genera of Microgastrinae with a similar, complete transverse carina on the propodeum: Beyarslania, Clarkinella, Neoclarkinella, and Prasmodon. However, they all appear to be only distantly related to Mariapanteles because they all lack a sharp median groove on mediotergite 1 and/or have an areolet in the fore wing.
The described species of Pseudapanteles never have a complete transverse carina. Most of the specimens in collections just have a simple median carina, with only few species having irregular transverse striations arising along the length of the median carina (but even in those cases they never reach the spiracle and never form a fork around them). One example can be seen in the original description and pictures of the species Pseudapanteles gouleti Fernández-Triana, from Canada (Figure 18, page 24, in Fernández-Triana 2010). However, the carination pattern is not comparable to a complete transverse carina – as displayed by Mariapanteles.
The presence of a bifurcate glossa is a strong autapomorphy for Pseudapanteles (it is only present in three other distantly related Microgastrinae genera: Napamus, Promicrogaster and Sendaphne). Furthermore, the differences between Mariapanteles and Pseudapanteles with respect to the pleated area of the hypopygium are also consistent in the separation of these two genera.
Currently Pseudapanteles has nine described species (Yu et al. 2009), and a wide distribution within the New World, ranging from Canada to South America (one of the species has also been introduced to Hawaii (Coulson 1992)). The actual number of species is much higher, and we have seen in collections several dozen undescribed species, mostly from the Neotropics. The vast majority of those specimens are remarkably invariant in having a bifurcate glossa and in lacking a transverse carina on the propodeum.
For all of the above reasons along with the molecular results, we have decided that Mariapanteles is a distinct, separate genus that may be closely related to Pseudapanteles.
As for the former records of Neotropical species of the genus Beyarslania (at that time called Xenogaster) (Whitfield 1997; Campos 2001), these are based on confusion with specimens of what we have described here as Mariapanteles. Based on the available evidence, we now consider Beyarslania to be restricted to the African tropics. The Neotropical specimens thought to belong to that genus should be identified as Mariapanteles.