Helenanomalon, Broad, 2014

Broad, Gavin R., 2014, A new, endemic genus of Anomaloninae (Hymenoptera, Ichneumonidae) from St Helena, Journal of Hymenoptera Research 41, pp. 31-45 : 33-34

Helenanomalon gen. n.

Type species.

Helenanomalon bonapartei sp. n.

Description.

Eye surface with short hairs, shorter than spaces between them; eyes convergent ventrally; occipital carina complete, dorsally closer to rear ocellus than diameter of ocellus, ventrally reaching mandible base separate from hypostomal carina (difficult to see on the female specimens of H. ashmolei sp. n., cannot confirm for both species); frons simple, lacking median longitudinal or transverse carinae. Antenna long, potentially sexually dimorphic, simple in ♂ of H. bonapartei sp. n., very short and distinctly clubbed in ♀ of H. ashmolei sp. n., with subapical flagellomeres shorter and wider than basal flagellomeres (Fig. 6 ); flagellum lacking white band; scape from 1.4-2.3 × pedicel, truncate at shallow angle. Clypeus truncate (Fig. 3 ), edge thin and slightly outcurved; mandible strongly narrowed, slightly twisted, with upper tooth 2.0-2.6 × lower tooth. Maxillary palp with five segments, labial palp with four (in H. bonapartei sp. n., cannot confirm for H. ashmolei sp. n.), apical palpomere very small. [Cardo not dissected out.]

Pronotum rather short dorsally with narrow, sharply defined transverse furrow, anterior edge of furrow continuing ventrally as carina close to and parallelling anterior edge of pronotum; posterior, dorsal corner of pronotum not covering spiracular sclerite; lower anterior corner lacking tooth, rounded anteriorly. Mesoscutum steeply rounded anteriorly without an apical concavity. Notauli present or absent; transverse suture of mesoscutum absent, transverse furrows absent. Epicnemial carina reaching to about lower ⅓ of mesopleuron, dorsally distant from anterior margin of mesopleuron, medio-ventrally weakly raised; sternaulus absent; only short, median section of posterior transverse carina of mesosternum present.

Fore coxa smooth; fore tibial spur with long comb of macrotrichia on inner surface with membranous flange posterior to comb. Mid tibia with two spurs. Hind trochanter dorsally 2.0-3.0 × as long as trochantellus, ventrally 1.0 ×; hind tarsi of ♂ not swollen; hind tarsal claws abruptly curved, fully pectinate (Fig. 5a ), or weakly curved with only basal pecten (Fig. 5b ).

Fore wing with Rs straight; 2 rs-m basal to 2 m-cu; 1 m-cu and Cu 1 a basally separate (Fig. 9a, b ). 1st subdiscal cell approximately parallel-sided. Hind wing with 6 (♀) or 9-10 (♂) hamuli on vein R 1; distal abscissa of Cu 1 present, but not joining cu-a + basal section of Cu 1 (nervellus) (Fig. 9a ), or absent (Fig. 9c ).

Petiolar index:

PI (distance from anterior margin of 1st metasomal spiracle to base of 1st tergite / distance from posterior margin of spiracle to apex of 1st tergite) = 2.19-2.68.

Fore wing indices:

CI (length of Cu 1 between 1 m-cu and Cu 1 a / length of Cu 1 b between Cu 1 a and 1 A = 0.82-1.27;

BI (shortest distance between Cu 1 and 1 A at distal end of 1st subdiscal cell / shortest distance between Cu 1 and 1 A at proximal end of 1st subdiscal cell) = 1.09-1.13;

DBI (length of Cu 1 between cu-a and 1 m-cu / length of 1 m-cu between Cu 1 and 2+3 rs-m) = 0.49-0.51;

ICI (length of 2+3 rs-m / length of M between 2+3 rs-m and 2 m-cu) = 0.60-1.23;

MI (length of Rs / length of Rs + 2 r) = 1.60-1.89.

Hind wing index:

RI (length of Rs between R 1 and 1 r-m / length of 1 r-m between Rs and M) = 1.25-1.38.

Propodeum reticulate, with longitudinal, median depression; spiracle about 1.6 × as long as broad; apex of propodeum extending about 0.3-0.4 × length of hind coxa. Metasoma elongate.

♀ genitalia. Ovipositor sheath 1.2 × length of tergite 3; ovipositor lacking dorsal notch but pre-apically markedly swollen, higher and wider here than basal or apical sections, apical 0.3 of dorsal valves of ovipositor very narrow, slightly decurved (Fig. 7 ).

♂ genitalia. Metasomal tergites 8+9 (syntergum of Gauld 1976) entire; 8th sternite roundly produced posteriorly; parameres (=gonosquamae) approximately rectangular; gonolacinia smoothly curved, with median tooth; distivolsella not wholly visible in available specimens; aedeagus in profile distally swollen, convex dorsally with apical, dorsal projection, ventrally membranous with whole membranous area covered with minute spinules, not laterally expanded (Fig. 8 ).

Etymology.

Named after the type locality, St Helena, and the type genus of the subfamily, Anomalon .

Remarks.

The two available female specimens of H. ashmolei sp. n. are, in part, encrusted with glue and dirt so it is not possible to see all of the characters that can be observed in the male specimens of H. bonapartei sp. n. Sexual dimorphism seems to be pronounced in this genus, although each species is known from one sex only; see discussion below on the species status of specimens.

Figures

Figure 3. Face of a holotype ♂ of H. bonapartei sp. n. and b holotype ♀ of H. ashmolei sp. n.

Figure 5. Hind tarsal claw of a holotype ♂ of H. bonapartei sp. n. and b holotype ♀ of H. ashmolei sp. n.

Figure 6. Antenna of holotype ♀ of H. ashmolei sp. n.

Figure 7. Ovipositor of holotype ♀ (RMCA) of H. ashmolei sp. n.

Figure 8. Genitalia of paratype ♂ (RMCA) of H. bonapartei sp. n.

Figure 9. Wings of Helenanomalon species a fore and hind wings of paratype ♂ (BMNH) of H. bonapartei sp. n. b fore wing of holotype ♀ of H. ashmolei sp. n. c hind wing of H. ashmolei sp. n.