Psyllaephagus migrator McClelland 2025, sp. nov.
Creators: name: McClelland, Alana R.
name: Moore, Matthew R.
name: Bremer, Jonathan S.
name: Talamas, Elijah J.
name: Halbert, Susan E.
name: Singarayan, Virgine T.
name: Brown, Bradley T.
name: Purcell, Matthew F.
name: Brookes, Dean R.
name: Hentz, Matthew G.
Publisher: name: Zenodo
Year: 2025
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hymenoptera
Encyrtidae
Psyllaephagus
Psyllaephagus migrator

description: Psyllaephagus migrator McClelland sp. nov.
Figs 5, 6, 7
Material examined.
Holotype. USA • Female (FSCA): “ USA – Florida, St. Lucie Co., Port St., Lucie. Peacock Run Apartments. 27.3462297 N, 80.3827508 W. 17 THApril 2023; M. Hentz; reared from parasitized nymphs of Boreioglycaspis melaleucae ”. Genbank accession numbers: PP 840072; PP 837614; PP 833159; PP 831170; PP 840063. BOLD: PMIG 006-24 Specimen deposited at FSCA, accession number: FSCA 00094033.
Allotype. USA • Male (FSCA): Collection data as for holotype. Genbank accession numbers: PP 840071; PP 837613; PP 833160; PP 831169; PP 840064. BOLD: PMIG 005-24. Specimen deposited at FSCA, accession number: FSCA 00094034.
Paratypes: Collection data as for holotype, 32 females, 31 males deposited as follows: QM 7 female, 12 male; FSCA 18 female, 13 male; USNM 2 female, 1 male; CDFA 1 female, 1 male; EMEC 1 female, 1 male: CASC 1 female, 1 male; NHMUK 2 female, 2 male.
Additional material.
USA • 3 Female, 2 male, point mounted: “ USA- Florida, St. Lucie Co., Port St. Lucie, 5532 NW E. Torino PKWY 27.34557 N, - 80.37937 W. 8 th April 2023; M. Hentz ”. QM accession numbers: T 260235 - T 260239.
AUST • 2 Female, 2 male, 1 unspecified, point mounted: AUST – “ Qld, Peregian Environmental Park, 5 th July 2023. Reared from parasitized B. melaleucae collected from M. quinquenervia leaves ”. QM accession numbers: T 260240 - T 260244.
See Suppl. material 1 for repository accession numbers, and Suppl. material 2 for sequence data and Genbank and BOLD accession numbers of paratypes and additional material.
Diagnosis.
Psyllaephagus migrator is a small species with purple head, blue mesoscutum, axilla and scutellum; axilla is smooth by comparison to the mesoscutum and scutellum; blue propodeum with long pale hairs on the lateral surfaces. Dark green mesopleuron and metasoma with coppery reflections. Reticulated sculpturing, reticulate-rugulose on the mesoscutum, scutellum and head.
A key to 60 of the 122 Australian Psyllaephagus fauna was published by Riek (1962). When assessing the female holotype of P. migrator against this key, the key terminates at couplet 43 (44) P. discretus. Psyllaephagus migrator differs from P. discretus in head, club and coxal color. Specifically, in the description for P. discretus the head color is described as green, antennal club slightly darkened, mesocoxa slightly darkened at base and metacoxal dark. Psyllaephagus migrator has a purple head with blue reflections, light brownantennal club, and all coxae are yellow ..
The Australian species that are not included in Riek’s key have been morphologically examined and were eliminated. Specifically, the three species described by Walker (1839) all have a significant space between the posterior ocelli and the eye margin, whereas Psyllaephagus migrator has a marginal space. The key morphological differences separating the new species from the other described Australian species, P. iridus, are leg color (yellow in P. migrator versus dark brown / bi-colour in P. iridus) and peg pattern on the basitarsus (two sharply angled opposing rows of pegs in P. migrator versus one continuous row of pegs in P. iridus). Males of P. iridus also have very distinct yellow-ended, capitate antennae. As in McClelland et al. (2023), Psyllaephagus migrator is not diagnosed against the Australian species described by Girault due to the morphologically uninformative state of his type specimens.
Psyllaephagus migrator was diagnosed against the valid North American species (Suppl. material 3) and superficially resembles P. pachypsyllae, known only from North America (Noyes, 2023). P. migrator differs from P. pachypsyllae in the characteristics of the tegula. The tegula base in P. migrator is dark brown in females, light brown in males. The tegula in P. pachypsyllae is pale yellow at the base.
Description.
Females can be identified by the following combination of characters: prepectus dark brown anteriorly with white posterior edge; tegula light brown, sometimes with darker brown patches; legs pale yellow, apical segments with dark brown tips; mesotarsus with distinct row of orange pegs on underside; mesotibial spur stout; base of metatibia fringed with stout orange hairs; ovipositor slightly extruded; three very long cercal hairs; dark brown scape; space between posterior ocelli and eye margin less than a quarter diameter of ocelli; distance between posterior ocelli slightly greater than distance between posterior and anterior ocelli; pedicel and first two funicle segments dark brown, remaining segments light brown flagellum clavate with fine, pale setae and slight but discernible space between funicle segments.
Males smaller than females, with green reflections (where females are blue) and with reticulate sculpturing as in females. Additionally, the following characters can be used to identify males of Psyllaephagus migrator: Prepectus dark brown anteriorly with white posterior edge, tegula light brown, sometimes with darker brown patches; legs pale yellow, tarsomeres light brown; tarsal characters as for females; space between posterior ocelli and eye margin approximately one third diameter of ocelli; distance between posterior ocelli almost twice distance between posterior and anterior ocelli; scape yellow pedicel dark brown; antenna serrate, light brown, with short pale setae; small but distinct space between funicle segments.
All measurements are in millimeters.
Female. Body. Length excluding ovipositor 1.53. Body blue except for mesopleuron, metasoma and gaster which are green with copper reflections (Fig. 5 A, I). Reticulate sculpture, smoother on axilla and gaster, reticulate-rugulose on rest of mesosoma (Fig. 5 I). Ovipositor mildly extruded, approximately 1.2 × the length of mid tibial spur (Fig. 5 C, E) length 0.09 (Fig. 5 C). Thorax covered with sparse, evenly distributed, short coarse setae (mesopleuron smooth); pronotum length: width 0.03: 0.54, mesoscutum length: width 0.32: 0.49. Tegula and prepectus dark brown, prepectus extends to tegula (Fig. 7). Legs pale yellow, apical tarsal segments with dark brown tips (Fig. 5 A). Mesotarsus with two distinct angled rows of orange pegs on underside (Fig. 5 E); length 0.13; apical tarsal segment 0.09. Metatibia fringed with setae, increasing in length to form a point (Fig. 5 E). Gaster with coppery reflections, cercal plate pronounced, long cercal setae approximately 1 / 3 the length of gaster (Fig. 7). Gaster length 0.72; width 0.33. Fore and hind wings hyaline with short setae almost uniformly distributed (except for linea calva and naked basal area of fore wing) (Fig. 5 H). Fore wing length 1.28; hind wing length 0.82; fore wing MV length. 53; fore wing PMV length 0.03; fore wing STV length 0.09.
Head. Length excluding mandibles 0.42; width (frontal view) 0.55; depth (lateral view) 0.28. Head purple with blue reflections, dense reticulate sculpturing, sparse setae (Fig. 5 F, G). Mandible pale, almost white (Fig. 5 F). Posterior ocelli with small distance between them and eye margin (Fig. 5 G). POL 0.1; AOL 0.07; OOL 0.007. Malar space 0.12. Eye length 0.33; width 0.26. Scape mildly expanded on underside, narrowest at base; dark brown with pale tip below pedicel; carination not obvious (Fig. 5 B); length 0.2. Pedicel dark brown in the basal ¾, paler brown at apex; length 0.08; width 0.03. Antenna clavate, light brown; uniform setae on each funicle; minimal distance between funicle segments 0.004 (Fig. 5 B). Funicle length: width; F 1 0.05: 0.03; F 2 0.04: 0.03; F 3 0.05: 0.03; F 4 0.05: 0.03; F 5 0.04: 0.04; F 6 0.05: 0.04. Club length 0.13; width 0.06.
Male. Body. Length 1.01. Body green with blue reflections on head and thorax, copper reflections on gaster (Fig. 6). Sculpture reticulate, smoother on axilla and gaster, reticulate-rugulose on rest of mesosoma, pronotum and mesoscutum with uniform, pale setae (Fig. 6 A, F); pronotum (length: width) 0.04: 0.32; mesoscutum (length: width) 0.24: 0.36. Prepectus dark brown anteriorly with white posterior edge, tegula light brown, sometimes with darker brown patches (Fig. 6 A). Legs pale yellow with light brown tarsomeres, basitarsus length 0.07; apical tarsal segment 0.07 (Fig. 6 A). Gaster dark green with copper and blue reflections (Fig. 6 A) (length: width) 0.38: 0.22. Fore and hind wings hyaline with short setae almost uniformly distributed (except for linea calva and basal area of the fore wing) (Fig. 6 D). Fore wing length 0.93; hind wing length 0.6; fore wing MV length 0.34; fore wing PMV length 0.07; fore wing STV length 0.08.
Head. Length excluding mandibles 0.35; width (frontal) 0.41; depth (lateral view) 0.19. Reticulate sculpturing with short, pale setae uniformly covering head. Head dark green with blue reflections, becoming emerald as reticulation smooths and setae become sparser on the face (Fig. 6 B). Mandible very light brown. Posterior ocelli at a distance of approximately 1 / 3 of their diameter from the eye margin (Fig. 6 C). POL 0.11; AOL 0.06; OOL 0.012. Malar space (0.12; 0.13; 0.13, see comments below). Eye length 0.23; eye width 0.19. Scape mildly expanded on underside, narrowing towards base, yellow, carination not obvious, covered in pale setae (Fig. 6 B, C); length 0.09. Pedicel uniformly dark brown; length 0.05; width 0.04. Antenna serrate, light brown, shaft light brown; dense, uniform pale setae on each funicle (Fig. 6 E); distance between segments 0.006. Flagellomere length: width; F 1 0.08: 0.04; F 2 0.07: 0.06; F 3 0.08: 0.08; F 4 0.08: 0.07; F 5 0.11: 0.06; F 6 0.09: 0.04.
Host.
Boreioglycaspis melaleucae Moore
Distribution.
Currently only known from the type locality in Florida, USA and southeastern Queensland, Australia. However, the species is likely to be more broadly distributed given that its host psyllid, Boreioglycaspis melaleucae, has spread to all 22 central and southern Florida counties, and has been collected and recorded from all Australian states and territories except South Australia (Burkhardt 1991). The psyllid’s host plant, Melaleuca quinquenervia is a widespread invasive plant in Florida and is recorded from coastal regions of all Australian states and territories.
Etymology.
The species epithet, migrator, meaning wanderer or immigrant in Latin and references the vast distance between the locations where the species has been collected.
Comments.
The malar space on the male allotype is partially obscured and so the measurement given is taken from three other males in the type series. In females, it is difficult to accurately measure the ovipositor without dissecting and slide mounting the specimen and so the decision is made to measure the extrusion of both sheath and stylets past the terminal end of the outer ovipositor plate, in lateral view. In both sexes, the pronotum is difficult to measure as it curves markedly and is very small. The length is taken at the midpoint of the pronotum, dorsally, with the body not tilted.
Although not exclusively suitable for morphological diagnosis, we also present images of the immature stages of P. migrator (Fig. 8) completing a set of high-resolution biological and diagnostic images from host to adult.
description: Published as part of McClelland, Alana R., Moore, Matthew R., Bremer, Jonathan S., Talamas, Elijah J., Halbert, Susan E., Singarayan, Virgine T., Brown, Bradley T., Purcell, Matthew F., Brookes, Dean R. & Hentz, Matthew G., 2025, You can run, but you will never escape: A new species of Psyllaephagus Ashmead (Hymenoptera, Encyrtidae), parasitoid of the classical biological control agent Boreioglycaspis melaleucae (Moore) (Hemiptera, Aphalaridae) in Florida, USA, pp. 95-116 in Journal of Hymenoptera Research 98 on pages 95-116, DOI: 10.3897/jhr.98.133593