Two new reared species of Heteropteron Brullé (Hymenoptera, Braconidae, Cardiochilinae) from northwest Costa Rica, with the first definitive host records for the genus

Two new Costa Rican species of the braconid parasitoid wasp subfamily Cardiochilinae, Heteropteron kidonoi Dabek & Whitfield and Heteropteron hasagawai Dabek & Whitfield, are described and illustrated from dry forest in the Area de Conservacion Guanacastae, along with data on rearing from their hosts. Heteropteron kidonoi is a solitary endoparasitoid of Stenoma cathosiota (Lepidoptera: Depressariidae) on Roupala montana (Proteaceae), while H. hasagawai is a solitary endoparasitoid of Carthara abrupta (Lepidoptera: Pyralidae) on the same host plant, but typically at slightly higher elevation localities. Diagnostic characters are provided to distinguish these two new species from each other, and also from the three previously decsribed species of Heteropteron. Heteropteron kidonoi and H. hasagawai are the first species of Heteropteron to have any host data, and also are the first to be reported in Costa Rica.


introduction
We report here the description of two new reared species of the relatively rare yet large and colorful cardiochiline braconid wasp genus Heteropteron, from the Area de Conservacion Guanacaste (ACG) in northwest Costa Rica. The descriptions are notable for adding significantly to our understanding of the geographic distribution, habitat specialization and host natural history of this unusual genus. The specimens and data supporting the descriptions arise from the long -term rearing inventory of ACG (Janzen et al. 2009).
The definition of Heteropteron has had a somewhat confusing history, even in recent years. After first being erected by Brullé (1846) for the unusual slender and polished cardiochiline species H. macula Brullé, several other somewhat similar-looking Neotropical genera were later described: Wesmaelella Spinola, (1853) based on W. rubricollis Spinola, Psilophthalmus Szépligeti, (1902) based on P. nigripennis Szépligeti, and Neocardiochiles Szépligeti, (1908) based on N. fasciipennis Szépligeti. Schulz, (1911) synonymized Psilophthalmus under Wesmaelella and this synonymy has been maintained ever since. The remaining three genera were still considered as distinct as recently as Whitfield and Dangerfield (1997), but two years later Dangerfield et al. (1999) synonymized all three with Heteropteron as the senior synonym. Shortly afterward Mercado and Wharton (2003) pulled Wesmaelella (including Psilophthalmus) out of synonymy with Heteropteron, an arrangement agreed with by Papp (2014), with some reservations still due to confusion in the interpretation of some types. Due to museum loan limitations at the relevant museums, it has never been possible to compare all the types with one another simultaneously, but the situation has been clarified considerably in the last 20 years, and Papp's conclusions are adopted here. Heteropteron appears to be relatively early-diverging within Cardiochilinae based on both morphological and molecular evidence (Dangerfield et al. 1999;Murphy et al. 2008).
As a result of this history, Heteropteron currently has 3 described species: H. fasciipennis (Szépligeti), H. macula Brullé, and H. whitfieldi Mercado. All are known from the Neotropical Region, ranging from Mexico to Brazil, primarily in wet tropical forest. None of the three has any recorded hosts. The two new species described below most closely resemble H. fasciipennis in general appearance, probably belonging to the same color pattern mimicry complex but differing in mesosoma coloration (dark in H. fasciipennis, yellowish orange in the two new species) and other less obvious features such as hypopygium shape and slightly more complex spination of the pectinate tarsal claws). Little is known about this mimicry complex, but similar color patterns are found in the same region among some Heteroptera (Hemiptera) as well as among several other subfamilies of Braconidae, especially Braconinae and Agathidinae.
We do have new host data, however, for both species, constituting the first host records for the genus. Heteropteron kidonoi sp. nov. , described below, attacks caterpillars of Stenoma cathosiota (Depressariidae) (Fig. 1A) on the dry forest shrubby evergreen tree Roupala montana (Proteaceae); its very similar congener H. hasagawai sp. nov., also described below, specializes on the caterpillars of Carthara abrupta (Pyralidae) ( Fig. 1B) on the same host plant species, usually at slightly lower elevations. Carthara abrupta, as currently defined, feeds on a variety of plants; the form that hosts H. hasagawai is referred to informally as Carthara abruptaDHJ02. H. kidonoi spins its cocoon within that of the host (Fig. 2); presumably H. hasagawai does as well, but we do not have direct documentation of that.
There were also no previously described species of Heteropteron recorded for Costa Rica.

Methods
Morphological terminology follows that used in Huber and Sharkey (1993) with usage specific to the microgastroid lineage Braconidae from Dangerfield et al. (1999) and Fernandez-Triana et al. 2014. Photographs were taken at the University of Illinois using a Leica M205 C stereo microscope (467 nm resolution) fitted with a five megapixel Leica DFC 425 digital microscope camera. Image stacking was achieved using a motor drive on the scope and the Leica z-stacking software. Body length excluding head. Average male, 7.5 mm; average female, 8.0 mm. Body color (Fig. 3): Mesosoma pale except anterior propleuron dark, head black, metasoma variable with majority (31/42 specimens) with terga 6-8 dark, 1-5 pale. Antenna color: scape, pedicel, and flagellum dark. Coxa, trochanter, trochantellus dark. Forefemur variably pigmented, ventrally dark toward center. Tibia, tarsus, tibial spurs light. Pretarsus and tarsal claws dark, aroliar pad dark (Fig. 5D). Wings alternately banded light and dark (Figs 3A, B, 4C).
Face (Fig. 4A) 1.6 × broader than high. Galea dark, 1.5 × longer than wide. Glossae light, bilobed, similar in shape to galea: semicircular distally. Frons smooth, deeply excavated, excavation extending longitudinally from base of antennae to vertex and transversely from inner margin of left eye to inner margin of right eye. Frons dorsally with Y-shaped shallow ridge, with branches terminating immediately anteriorad median ocellus (Fig. 4B). Ocelli elevated within excavation with some setae. Small ridge evident at antennal base. Antenna with 36-37 flagellomeres.
Mesosoma. Pronotal collar unsculptured except for marginal ridges anteriorly and posteriorly with visible setal pits, lateral pronotum sculptured ventrally, reaching mesopleuron and dark in color, dorsally transitioning to light color with groove reaching subalar depression. Notauli smooth, incomplete, distinct anteriorly, evanescent posteriorly, extending about half length of mesoscutum; mesoscutum smooth, about as broad as long, flattened dorsally in lateral view, medial lobe bulging anteriorly, sparsely covered with brownish yellow setae.
Scutellum triangular, smooth, flat in lateral view, lateral areas bare and smooth. Posterior end of scutellum margined by ridge (Fig. 3A).
Metanotum smooth. Propodeum smooth, areola with complete longitudinal furrow, narrowing anteriorly, margined by weak carinae; pilosity moderate with high abundance in vicinity of spiracles. Setae near areola 10 × longer than distance between adjacent setae; spiracles 1.8 × longer than wide. Sternaulus indistinct, episternal scrobe present, sometimes weakly indented, not extended to sternaulus. Subalar depressions smooth with median carina forming obtuse angle. Subalar prominence tapering posteriorly to pleural sulcus, smooth, convex. Pleural sulcus with double grove. Posterior margin of mesopleuron smooth. Mesopleuron (Fig. 5A) smooth, lightly setose ven- Legs. Hind tibia gradually broadening distally, distal end 1.8 × as broad as proximal end. Hind femur 5 × as long as broad distally. Hind basitarsus same length as tarsomeres 2-5 combined, inner spur of hind tibia half the length of basitarsus. Second tarsus of fore leg 1.4 × longer than broad, fifth tarsus of foreleg 1.6 × longer than broad; second tarsus of mid leg 1.7 × longer than broad, fifth tarsus of mid leg 1.7 × longer than broad; second tarsus of hind leg 1.7 × longer than broad, fifth tarsus of hind leg 1.5 × longer than broad. Tibial spines, up to 12, generally > 6 in two alternating rows, variable in number and pattern. (Fig. 5C).
Wings. Forewing 1.15 × longer than body. Pterostigma elongate, issuing r from its middle. Second submarginal cell long. Color pattern as in Fig. 4C.
Cocoon. Elongate, silk light tan externally and white internally, spun within the cocoon of its host (Fig. 2).
Etymology. Heteropteron kidonoi is named in honor of Dr. Hiroshi Kidono (retired) of Japan International Collaboration Agency (JICA), who first came to ACG in 1992 and has since then, and hopefully many years more, been a major supporter of all aspects of ACG, ranging from financing to Hesperiiidae taxonomy to female parataxonomists to international conservation biopolitics.
Face (Fig. 7A) 1.8 × broader than high. Galea dark, 1.2 × wider than long. Anterior tentorial pits very distinct, deep. Glossae light, bilobed. Frons smooth, deeply excavated, excavation extending longitudinally from base of antennae to vertex and transversely from inner margin of left eye to inner margin or right eye. Frons dor- sally with distinct Y-shaped ridge with branches terminating immediately anterior to median ocellus (Fig. 7B). Ocelli elevated within excavation with some setae between. Visible ridge at antennal base. Antenna with 34-36 flagellomeres.
Mesosoma. Pronotum unsculptured except weakly on marginal ridges anteriorly and posteriorly, long light yellow setae anterodorsally. Pronotum light in color later- ally and posterodorsally, dark anteriorly and ventrally. Notauli smooth, incomplete, distinct anteriorly, evanescent posteriorly, extending about half length of mesoscutum; mesoscutum smooth, 1.1 × wider than long, flattened dorsally in lateral view, sparsely covered with yellow setae. Scutellum triangular, smooth, flat in lateral view, lateral areas of scutellum bare and smooth. Posterior end of scutellum lacking ridge at margin (Fig. 6A).
Propodeum smooth, virtually without areola but with complete longitudinal furrow; pilosity abundant in vicinity of spiracles. Setae 6 × longer then distance between each setae; spiracles 1.4 × longer than wide. Subalar depression smooth with median carina forming obtuse angle. Subalar prominence tapering posteriorly to pleural sulcus, smooth, convex. Pleural sulcus with double groove. Posterior margin of mesopleuron smooth, moderately setose ventrally with visible setal pits. Mesopleuron smooth (Fig. 8A). Metapleuron with distinct dorsal-ventral groove starting halfway down the dorsal edge of the metapleuron and ending at the posterior end, moderately setose, setae light in color.
Legs. Hind tibia slightly broadening distally, distal end 1.8 × as long as proximal end. Hind femur 2.6 × as long as broad distally, distal end 2.1 × as long as proximal end. Hind basitarsus 1.2 × the length of tarsomeres 2-5 combined, inner spur of hind tibia half the length of basitarsus. Second tarsus of fore leg 1.4 × longer than broad, fifth tarsus of foreleg 1.7 × longer than broad; second tarsus of mid leg 1.3 × longer than broad, fifth tarsus of mid leg 1.3 × longer than broad; second tarsus of hind leg 1.7 × longer than broad, fifth tarsus of hind leg 1.3 × longer than broad. Tibial spines, generally < 7, variable in number and pattern (Fig. 8C).
Forewing. 1.15 × longer than body. Pterostigma elongate, issuing r from its middle. Second submarginal cell long. Banding pattern as in Fig. 7C.
Host. Caterpillars of Carthara abrupta (Pyralidae) on Roupala montana (Proteaceae). Carthara abrupta, as currently defined, feeds on a variety of plants; the form that hosts H. hasagawai is referred to informally as Carthara abruptaDHJ02.
Etymology. Heteropteron hasegawai is named in honor of Dr. Motohiro Hasegawa of Japan International Collaboration Agency (JICA), who first came to ACG in 2015 and has since then, and hopefully decades more, been a major supporter of all aspects of ACG, ranging from financing to biomonitoring of a geothermal electricity project with insect thermometers to biodevelopment to DNA barcoding to international conservaton biopolitics.
Diagnosis. This new species differs from H. fasciipennis most obviously in having a yellowish orange (in older specimens occasionally somewhat brownish) mesosoma rather than mostly blackish. From H. kidonoi, described above, it can be distinguished by its slightly to significantly lighter yellowish portions of the metasoma (Figs 6, 8A), more truncately pointed hypopygium tip (Fig. 8B), less numerous and more linearly arranged small spines on the mid tibia (Fig. 8C), and the whitish tarsal arolia (Fig. 8D).