Leseha vespa Smith & Nishida, 2019

Smith, David R. & Nishida, Kenji, 2019, A new genus and three new species of Neotropical sawflies (Hymenoptera, Tenthredinidae) from Costa Rica, with host plants and life history notes, Journal of Hymenoptera Research 72, pp. 45-65 : 45

Leseha vespa Smith & Nishida sp. nov.

Figs 16-23 , 24-30 , 31-37 , 53

Diagnosis.

Largely black with reddish-brown to yellow spots on head, thorax, and transverse stripes on abdomen ( Fig. 16 ). Lancet ( Fig. 20 ) very short, without distinct serrulae or annuli. Male with concave area on apical tergite.

Description.

Female ( Fig. 16 ): Length 9.5 mm. Antenna with scape yellow, pedicel and flagellum reddish brown, 4th antennomere to apex sometimes darker brown than pedicel and 3rd antennomere. Head mostly yellow with black marks; black on postocellar area, broad stripes from lateral ocelli almost to antennal insertions, area surrounding front ocellus, spot on occiput above each eye, spot above interantennal area, narrow bands surrounding antennal sockets. Thorax mostly yellow with black marks on center of mesoscutal middle lobe, lateral lobes except sides, downturned lateral sides of lateral lobes, mesoscutellar appendage, area between cenchri, mesosternum, line separating epicnemium, and spot on lower margin of propleuron. Legs yellow with black stripe on outer surface of hind femur. Abdomen with first 2 segments mostly yellow, segments 3 to apex mostly black above, apical 3 or 4 segments black. Sheath reddish brown at apex, black at base. Wings lightly, uniformly hyaline, costa and stigma yellow, other veins black. Head and thorax shiny, without sculpture, abdomen dull densely microsculptured. Head ( Figs 17 , 18 ): Antennal length 2.0 × head width; scape and pedicel about as long as broad, 3rd antennomere slightly longer than 4th, as 1.0:0.8; antennomeres 4 to apex slightly decreasing in length, slightly thickened at antennomeres 5-7. Clypeus with shallow, circular emargination. Malar space less than half diameter of front ocellus. Lower interocular distance slightly longer than eye height, as 1.0:0.9. Distances between eye and lateral ocellus, between lateral ocelli, and between lateral ocellus and hind margin of head as 1.0: 0.6:1.0; postocellar area about 1.6 × broader than long. Thorax: Hindbasitarsus subequal in length to remaining tarsomeres combined; hind tibial spurs subequal in length, about as long as width of hind tibia at apex. Abdomen: Sheath ( Fig. 19 ) in lateral view narrow, slightly turned up at apex, dorsal margin slightly concave, ventral margin rounded, tapering to narrowly rounded apex; in dorsal view broad at base, tapering to narrow rounded apex, with long, fine hairs. Lancet ( Fig. 20 ) very short; serrulae and annuli barely discernable.

Male: Length, 8.0 mm. Color similar to female. Apex of abdomen ( Fig. 21 ) with deep, oval concavity dorsally: 7th tergite emarginate and with ridge at apex, 8th tergite deeply concave. Genitalia in Figs 22 , 23 ; harpe rounded; parapenis rounded at apex, slanted laterally; valviceps of penis valve with long,narrow apical lobe and long narrow dorsal lobe.

Larva: Last feeding instar ( Figs 34 , 35 ): Length 18-24 mm. Head black, width ca. 2.2 mm. Body pale green with yellowish tint, yellowish tint more visible on thoracic segments 2 and 3, and abdominal segments 7-10 and abdominal tergum 1 yellow, lateral lobes of thoracic segments 2-3 yellow, thoracic legs black, spiracular to proleg area of abdominal segments 1-10 creamy white (n = 7).

Type material.

Holotype female, labeled "COSTA RICA, Puntarenas Province, Monteverde, Estación Biológica Monteverde, 1530 m, 10°19'08.5"N, 84°48'32.0"W, larvae 15.v.2017, adults 22-25.vi.2017, Phlebodium pseudoaureum , Kenji Nishida (USNM). Paratypes: Same data as for holotype (2 ♀, 2 ♂, MZUCR, USNM); same data as for holotype except mid-May 2018, in flight and perched on leaves (1♀, MZUCR); adult emerged 26.viii.2018, Phlebodium areolatum (5 ♀, 2 ♂, USNM, MZUCR); larvae 15.viii.2018, emerged 17.viii.2018, Phlebodium areolatum (1 ♀, MZUCR); collected on Phlebodium areolatum , 14.vi.2018 (1 ♀, MZUCR); adult emerged 10.viii.2018, Phlebodium areloatum (3 ♀, USNM, MZUCR); adult emerged 21.viii.2018, Phlebodium areolatum (1 ♀, USNM); Costa Rica, S. J., San Antonio de Escazu, 1325 m, W. G. Eberhard, 12.VIII.2018, vouchers study of W. Eberhard (1 ♀, 2 ♂, USNM).

Etymology.

The name Leseha vespa is Latin for wasp. This species resembles a commonly seen yellow and black striped paper wasp, an Agelaia sp. ( Vespidae ), at the same habitat of the study site in Monteverde.

Host, life history.

The larvae feed on Phlebodium pseudoaureum ( Polypodiaceae ). In the native plant garden of EBM, P. pseudoaureum ferns were growing in patches ( Fig. 24 ). Between May and June of 2017 and 2018, vigorous growths of new shoots and young fronds were observed. In May 2017 and 2018, some yellow and black striped paper wasp-looking sawfly females were observed walking on the host fern. Between 10:12 AM and 10:55 AM, the females laid ca. 1.5 mm long purple or yellow eggs ( Figs 25 , 26 , 28 , 29 ) on the abaxial of the blade ovipositing from the adaxial, i.e., oviposited piercing the ovipositor through blade tissue (n = 3) ( Figs 16 , 25-29 ). On young, soft and succulent fronds, eggs were laid mostly on leaf veins (n = 12 fronds) and on old and tough fronds, were laid on the blade (n = 10 fronds). Pierced holes of oviposition were visible from adaxial. The females oviposited in small clusters of 2-7 eggs (n = 7 clusters). In a few cases singly laid eggs and eggs positioned on adaxial blade were observed. Under captive conditions, a female laid up to 58 eggs in 10 days. Regarding the color variation of the eggs, in the first days of oviposition the eggs were yellow and then became orangish, and last days became purple. The eggs became translucent and enlarged in 2-3 days, and formation of the larvae was visible inside ( Figs 28 , 29 ). A commonly seen earwig ( Ancistrogster spinax or A. scabilosa : Dermaptera ) placed in a petri dish quickly devoured 3 recently laid L. vespa eggs. Very recently hatched larvae were creamy-colored with light brown head and black stemmata ( Fig. 30 ). The light brown head became black and as the larvae fed on the blade tissue the body became greenish internally. The early instar larvae fed on soft and succulent blades making small holes ( Fig. 31 ) and grazed on tough blades ( Fig. 32 ). Early instar larvae on very old and tough fronds fed on sori, and the body color was pale brown ( Fig. 33 ) (n = 3). Late instar larvae fed on the entire blade leaving tough vein areas. In the dioramic chamber, pupation occurred under rocks and branches spinning dark brown ovoid cocoons (n = 18) ( Figs 36 , 37 ). Relatively mature pupae were greenish (n = 2) ( Fig. 37 ). Some of the dissected cocoons contained prepupal larvae which apparently were in diapause (n = 3).

A summary of collecting and rearing records is as follows: Eggs, early to late instar larvae on maturing fronds 12-16.vi.2008. Middle to late instar larvae on young fronds 15.v.2017, all went under soil 8-10.vi.2017, adult emergence 22-25.vi.2017; a female laid eggs 14.vi.2018, first instar hatched 22.vi.2918, last feeding instar 15-30.vii.2018, adult emergence 21.viii.2018; recently laid eggs 26-27.vii.2018, first instar hatched 4.viii.2018, middle to late instar larvae 27.viii.2018, adult emergence 22-30.ix.2018.

Remarks.

Phlebodium pseudoaureum is an epiphytic or terrestrial fern with up to ca. 30 pinnas or 2 cm width growing to ca. 1 m tall. Fronds are soft and succulent when young, when mature it becomes tough (crunchy). Abaxial of frond is thinly covered with a white, waxy substance. It is distributed between Mexico (vicinity of Topic of Cancer) to northern Argentina, including the Caribbean (Dominican Republic and Jamaica). In Costa Rica it has been recorded from near sea level to 2500 m elevations on both slopes ( Moran 2009; Missouri Botanical Garden 2018; KN personal observation 2017 - 2018). The species of the genus Phlebodium are closely related to Polypodium ( Tejero’Di’ez et al. 2009).

Eggs (n = 7) and some late-instar larvae were also found at 14°2'4"N, 87°4'29"W, ca. 1625 m elevation, in Reserva Biológica Monte Uyuca in Zamorano, Honduras (KN personal observation 2019). Although adults were not reared, these are most likely those of L. vespa based on the observation and the host pant.

The morphology, enlargement, and plant tissue association of the egg of this species are currently being studied by KN and Kondo Laboratory of Pattern Formation, Graduate School of Frontier Biosciences, Osaka University.

Figures

Figures 16 - 23. Leseha vespa 16 adult female, ovipositing 17 head, front 18 head, dorsal 19 sheath, lateral 20 female lancet 21 apical tergite of male 22 male genital capsule 23 male penis valve.

Figures 24 - 30. Leseha vespa 24 habitat where host plants occur (circles) 25 three freshly laid purple eggs on abaxial of mature old frond 26 freshly laid yellow eggs on abaxial of young frond of soft primary vein (note: frond was flipped upside-down for photography) 27 adaxial of Fig. 26 showing pierced holes of oviposition (arrows), ca. 0.2 mm 28 middle stage (3 - day old) purple orange and yellow eggs 29 clustered mature yellow eggs showing developing larva in each (note: mandibles stemmata, and thoracic legs are seen in reddish brown 30 just hatched first instar larvae (2.6 - 2.7 mm long, n = 30), an egg with developed larva inside (black stemmata), and remaining shrunk egg shells.

Figures 31 - 37. Leseha vespa 31 early stage first instar larva on abaxial blade and feeding scar as hole (s) on young frond (note green internal color of larva) 32 early stage first instar larvae scrape-feeding on abaxial blade of mature frond 33 middle instar larva feeding on sorus on mature tough frond (note brown internal color of larva) 34 last feeding instar larva, lateral view 35 last feeding instar larvae, dorsal view 36 cocoon (ca. 12 mm long) spun on surface of dry, mossy branch (enclosed in oval circle) 37 pupa in situ (cocoon is cut to show pupa).

Figures 51 - 55. 51, 52, 54, 55 Andeana sp. 53 Leseha vespa 51 head front 52 head dorsal 53 trsal claw 54 tarsal claw 55 hindwing.