Redescription and revision of the Neotropical genus Pseudoheptascelio Szabó (Hymenoptera, Platygastridae, Scelioninae), parasitoids of eggs of short-horned grasshoppers (Orthoptera, Acrididae)

Abstract The genus Pseudoheptascelio Szabó is redescribed and its species revised. We recognize four species: Pseudoheptascelio muesebecki Szabó, Pseudoheptascelio cornopis Masner, Pseudoheptascelio tico sp. n. and Pseudoheptascelio rex sp. n. The genus is found from Guatemala south to the Brazilian state of Rio Grande do Sul. The species Pseudoheptascelio cornopis is recorded as a parasitoid of the eggs of Cornops aquaticum (Bruner) on water hyacinth, Eichhornia crassipes (Mart.) Solms.


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The genus Pseudoheptascelio was described by Szabó (1966) from a single female collected in the state of Pará in northern Brazil. Masner (1972) subsequently erected Tanaoscelio for a single species collected in Trinidad and recorded as attacking the eggs of Cornops longicorne (Bruner) (Orthoptera: Acrididae, Leptysminae), a grasshopper that was being studied as a potential biological control agent for water hyacinth, Eichhornia crassipes (Mart.) Solms (Commelinales: Pontederiaceae). Masner (1976) later discovered an error in Szabó's original description concerning the presence of a complete radial vein in the hind wing. In fact, the tubular portion of the vein is abbreviated and does not reach the costal margin of the wing. Therefore, Masner concluded that these two taxonomic concepts were equivalent.
Pseudoheptascelio is found only in the New World tropics, from Belize and Guatemala south to southeastern Brazil. The distribution of the only known host, Cornops, is very similar, although its range extends north along the coasts of Mexico (Adis et al. 2007). Developments in our understanding of this group of grasshoppers subsequent to the original description of Tanaoscelio (Roberts & Carbonell, 1979) suggest that the species identification of the host should be updated. Cornops longicorne is now considered to be a junior synonym of C. frenatum (Marschall). This latter species, however, is terrestrial and its host plants are unknown (Roberts and Carbonell 1979). The only semi-aquatic species attacking Eichhornia in Trinidad appears to be C. aquaticum (Bruner) (Roberts andCarbonell 1979, Adis et al. 2007).
Appendix 1 lists terms associated with identifiers in the Hymenoptera Anatomy Ontology (Yoder et al. 2010). Identifiers in the format HAO_XXXXXXX represent concepts in the HAO version 2011-07-14 and are provided to enable readers to confirm their understanding of the concepts being referenced. To find out more about a given concept use the identifier as a search term at http://glossary.hymao.org. The identifier can also be used as a URI (universal resource identifier) by appending the identifier to 'http://purl.obolibrary.org/obo/' (e.g. http://purl.obolibrary.org/obo/ HAO_0000124). URLs in the format http://purl.org/net/hao/HAO_0123456 resolve to the HAO's community-based resource that includes additional images, notes, and other metadata.
In the Material Examined section the numbers prefixed with "OSUC" are unique identifiers for the individual specimens. The label data for all specimens have been georeferenced and recorded in the Hymenoptera On-Line database, and details on the data associated with these specimens can be accessed at the following link, hol.osu.edu, and entering the identifier in the form. Note the space between the acronym and the number.
Data associated with the genus Pseudoheptascelio can be accessed at http://hol.osu. edu/index.html?id=548. The generic and species descriptions were generated using a database application, vSysLab, designed to facilitate the production of a taxon by character data matrix, and to integrate those data with the existing taxonomic and specimen-level database. Data may be exported in both text format and as input files for other applications. The text output for descriptions is in the format of "Character: Character state (s)". Images and measurements were made using AutoMontage and Cartograph extended-focus software, using JVC KY-F75U digital camera, Leica Z16 APOA microscope, and 1X objectve lens. A standard set of images is provided for each species: dorsal habitus, lateral habitus, dorsal and lateral views of the head and mesosoma, and anterior view of head. Images are archived at Morphbank (www.morphbank.net) and in Specimage (specimage.osu.edu), the image database at The Ohio State University.
The electronic version of the paper contains hyperlinks to external resources. Insofar as possible, the external information conforms to standards developed and maintained through the organization Biodiversity Information Standards (Taxonomic Database Working Group). All new species have been prospectively registered with Zoobank (Polaszek et al. 2005, www.zoobank.org), and other taxonomic names, where appropriate, have been retrospectively registered. The external hyperlinks are explicitly cited in the endnotes so that users of the printed version of this article have access to the same resources. Life sciences identifiers, LSIDs, may be resolved at the specified URLs or at lsid.tdwg.org.
This work is conducted as part of the Platygastroidea Planetary Biodiversity Inventory. The authors made equal contributions. Antenna. Number of antennomeres in female: 12. Number of antennomeres in male: 10. Insertion of radicle into A1: parallel to longitudinal axis of A1. Shape of A1: more or less cylindrical, not flattened. Length of A3 of female: distinctly longer than A2. Number of clavomeres in female antenna: 7. Claval formula of female antenna: A12-A7/1-2-2-2-2-2. Arrangement of doubled multiporous plate sensilla on female clava: in longitudinal pairs. Tyloid distribution on male antenna: A5 only. Shape of male flagellum: subclavate.
Wings. Wing development of female: macropterous. Wing development of male: macropterous. Tubular veins in fore wing: present. Bulla of fore wing R: absent. Extent of marginal venation of fore wing: R1 reaching and ending at costal margin. Origin of r-rs in fore wing: arising before (basad of ) R/R1 attains costal margin. Development of basal vein (Rs+M) in fore wing: spectral. Development of R in hind wing: abbreviated, not attaining costal margin.
Diagnosis. Pseudoheptascelio cornopis is distinguished from P. muesebecki by the densely and finely sculptured vertex and the more elongate T5 (length/width 1.6-2.2).
Link Comments. In the brief key to species Masner (1976) stated that the stigmal vein (r-rs) is embedded in a milky spot, forming a pseudostigma. The species P. muesebecki, in contrast, was characterized as having the area around the stigmal vein transparent. We find that there is considerable variability in the development of the pseudostigma and that it is present in all specimens of Pseudoheptascelio. Pseudoheptascelio muesebecki Szabó, 1966: 167 (original description);Masner, 1976: 18 (type information).
Diagnosis. This species is very similar to P. cornopis, and it may be distinguished by the less elongate T5 and the coarse areolate sculpture on the vertex.
Diagnosis. This species shares the short female T6 (Fig. 22) and, in many specimens, the red mesosoma with P. tico. It may be distinguished by the short metascutellum (Fig. 20) and the absence of coriaceous microsculpture on the head and mesosoma.
Etymology. The specific epithet is Latin for king and should be treated as a noun in apposition.
Diagnosis. This species should only be confused with red specimens of P. rex. It may be distinguished by the well-developed coriaceous microsculpture on the head and mesosoma, and the elongate, deeply cleft metascutellum (Fig. 26).
Etymology. The specific epithet is a colloquial term for a Costa Rican, reflecting the origin of most of the specimens we have seen. It should be treated as a noun in apposition.
Link to Distribution Map. 17