Revision of Aleyroctonus Masner & Huggert (Hymenoptera, Platygastridae, Sceliotrachelinae)

The genus Aleyroctonus Masner & Huggert is revised. Aleyroctonus pilatus Masner & Huggert is redescribed, and two species are described as new: A. miasmus Lahey & Polaszek, sp. nov. (Australia) and A. stanslyi Lahey & Polaszek, sp. nov. (Australia). We consider Aleyroctonus to be most closely related to a complex of three morphologically similar genera: Aphanomerus Perkins, Austromerus Masner & Huggert, and Helava Masner & Huggert. Aleyroctonus is diagnosed from other genera of Sceliotrachelinae and a key is provided to the platygastrid genera of the Aphanomerus-cluster.


Materials and methods
The numbers prefixed with "NHMUK", "OSUC", and "USNMENT" are unique identifiers for the individual specimens (note the blank space after some acronyms). Details of the data associated with these specimens may be accessed at the following link: http://hol.osu.edu and entering the identifier in the form.
Abbreviations and morphological terms used in the text: sensillar formula of clavomeres: distribution of large papillary sensilla on the ventral clavomeres of the female (Yang et al. 2016), with the segment interval specified followed by the number of papillary sensilla (PS) per segment (e.g., A10-A8/1-2-2) (Bin 1981); LOL: lateral ocellar line, shortest distance between outer margins of the lateral and median ocellus (Masner 1980); OD: ocellar diameter, greatest width of ocellus; OOL: ocular ocellar line, shortest distance between inner orbit and outer margin of posterior ocellus (Masner 1980); POL: posterior ocellar line, shortest distance between inner margins of lateral ocelli (Masner 1980); T1, T2, ... T6: metasomal tergite 1, 2, ... 6; S1, S2, … S6: metasomal sternite 1, 2, … 6. Morphological terminology follows Masner and Huggert (1989), Mikó et al. (2007), and Lahey et al. (2019), except for that of the male genitalia which follows Johnson (1984). Morphological terms were matched to concepts in the Hymenoptera Anatomy Ontology (Yoder et al. 2010) using the text analyzer function. A table of morphological terms and URI links is provided in Suppl. material 1: Table S1. Photographs of card-or point-mounted insects were captured with a Z16 Leica lens, JVC KY-F75U digital camera, and Cartograph software, or using a Macroscopic Solutions Macropod Micro Kit with optical slices rendered in Helicon Focus. Image stacks of card-or point-mounted insects were processed with CombineZP to produce single montage images. Photographs of slide-mounted insects were captured with a Nikon DS-Fi1 camera attached to a Nikon Eclipse 90i compound microscope with DIC illumination. Image stacks of slide-mounted insects were processed with NIS Elements BR (version 3.22.01, Build 715) to produce single montage images. The single scanning electron micrograph was produced using the methods of Talamas et al. (2016). Montage images from the various imaging systems were postprocessed for exposure and contrast with Adobe Photoshop CC.

Collections
This work is based on specimens deposited in the following repositories:

ANIC
Australian

Facial and malar striae
Aleyroctonus is one of the few sceliotracheline genera with facial and malar striae. Normally, the malar sulcus serves as the boundary separating the facial striae (dorsal to the malar sulcus) from the malar striae (ventral to the malar sulcus). In Aleyroc-tonus, the precise position of this boundary is not clear because the malar sulcus is inseparable from the facial and malar striae in terms of surface sculpture. Despite this uncertainty, we use these terms to refer to the striae on either side of where we would expect the malar sulcus to be located based on our experience with other platygastroid genera.

Metascutellar setae
Setation of the metascutellum is uncommon within Platygastroidea, occurring in several genera of Scelionidae ( . Aleyroctonus is the only sceliotracheline known to us with a setose metascutellum, a character best observed when viewed posteriorly.

Aphanomerus-cluster
The Aphanomerus-cluster was loosely defined by Masner and Huggert (1989) and includes genera with or without foamy structures on the propodeum or metasoma; with basal costae, striae, or anterolateral pits on T2; different numbers of clavomeres; and an articulated, subcompact, or compact antennal clava. We retain use of this cluster until relationships among these genera are better understood, knowing full well that the genera included in this cluster may not form a monophyletic group.  (Figures 41, 42) (Austin and Field 1997).

Key to genera of the
Wings. Color of wings: hyaline. Wing development: macropterous. Length of fore wing: exceeding apex of metasoma. Marginal cilia of fore wing: present. Length of fore wing R: 1/3 length of fore wing. R of fore wing: tubular, remote from costal margin. Shape of knob of R: truncate. Cu of fore wing: spectral. M+Cu of fore wing: spectral. Marginal cilia of hind wing: present, longest along ventral margin. R of hind wing: present, 1/8 length of hind wing.  Male genitalia. Length of basal ring: 2/3 length of aedeago-volsellar shaft. Diagnosis. The presence of facial and malar striae, a distally pointed clypeus, 3-merous antennal clava, compound eyes with long setae, setation of the metascutellum, and the absence of foamy structures on the propodeum and metasoma separates Aleyroctonus from other members of Sceliotrachelinae. Excluding the clava, these characters are also present in males of the genus, facilitating the identification of specimens of either sex.
Link to distribution map. Comments. The distribution of this species is expanded to include northeast and southeast Queensland, Australia. In addition, Carver and Reid (1996) mentioned the presence of A. pilatus in Papua New Guinea; however, we did not examine specimens from that location.  Description. Body length of female: 1.21 mm (n=1). Color of radicle: black. Color of mesosoma: black. Color of metasoma: black. Length of LOL: less than 2 OD. Length of POL: approximately 2 OD. Genal carina: absent. Length of clava: not longer than A3-A7. Length of A4: clearly longer than A3. Shape of mesoscutum in lateral view: flat to slightly convex. Path of notauli: subparallel. Shape of notaulus: posteriorly dilated. Posterior mesoscutellar sulcus: incomplete medially. Setation of posterior mesoscutellar sulcus: sparse. Sculpture of posterior mesoscutellar sulcus: smooth. Rim of posterior mesoscutellar sulcus: absent. Sculpture of metanotal trough: smooth. Prespecular sulcus: present. Sculpture of prespecular sulcus: smooth. Setation of metapleuron: medially sparse. Length of metabasitarsus: as long or longer than tarsomeres 2-5. Setation of anterolateral pits on T2: dense. Rs of fore wing: nebulous. M of fore wing: nebulous. Rs+M of fore wing: spectral. Shape of ventral adeagal lobe: truncate.
Diagnosis. Aleyroctonus stanslyi is immediately recognizable by its short POL and posteriorly dilated notauli.
Etymology. Named in memory of Philip Anzolut Stansly (Professor of Entomology, University of Florida), former graduate advisor of the first author, authority on integrated pest management, and a world-renowned expert on the biological control of whiteflies. The epithet is treated as a noun in the genitive case.