Machaerothrix salticidus Binoy, Girish Kumar & Anju, 2020

Binoy, C., Anju, K., Kumar, P. Girish & Thejass, P., 2020, Description of a new species of spider wasp Genus Machaerothrix Haupt (Hymenoptera: Pompilidae) from India with reports on its host association and nesting behaviour, Zootaxa 4766 (1), pp. 192-200 : 193-196

Machaerothrix salticidus Binoy, Girish Kumar & Anju sp. nov.

( Figs 1–20 )

urn:lsid:zoobank.org:act:625FEE26-6E2D-49B7-B0F3-F1A4731860E6

Type material. Holotype ♀, India: Kerala, Kozhikode district , ZSIK campus (11°15’50.2”N, 75°47’11.5”E, 11 m), 23.xi.2019, Coll. P. Girish Kumar, ZSIK Regd. No. ZSI/ WGRC /IR/INV.13437 . Paratypes. 4 ♀, 5 ♂, same labels as holotype, ZSIK Regd. Nos. ZSI/ WGRC /IR/INV.13438–13446; 4 ♀, 4 ♂, Kerala, Kannur district, near Kannapuram mangrove (11°57’55.6”N, 75°18’38.9”E, 7 m), 04.ii.2019. Coll. C. Charesh; 1 ♀, 1 ♂, Kerala, Kozhikode district, Purameri (11°40’25.68”N, 75°37’56.52”E, 20.42 m), 27.vii.2018, Coll. K.P. Hanima Raveendran, ZSIK Regd. Nos. ZSI/ WGRC /IR/INV.13455, 13456; 1 ♂, Kerala, Wayanad district, Vellamunda (11°44’00.8”N 75°56’15.4”E, 1066 m), 12.vi.2016, Coll. P. Girish Kumar, ZSIK Regd. No. ZSI/ WGRC /IR/INV.13458; 1 ♀, Kerala, Wayanad district, Mananthavadi (11°48’4.91”N, 76° 0’15.74”E, 764.13 m), 17.xi.2017, Coll. P. Girish Kumar, ZSIK Regd. No. ZSI/ WGRC /IR/INV.13457.

Diagnosis. This new species runs close to M. johni Wahis in the key to species of Machaerothrix Haupt ( Wahis & Krombein 2000; Lelej & Loktionov 2014) in having a similar venation and a colour pattern of female melanistic form. However, the new species differs from M. johni as follows: males are completely black or black with brownish black at parts without any yellow colourations (in M. johni the metasoma has yellow marking); males with lateral edges of clypeus produced and weakly inwardly emarginated medially, margins carinate (in M. johni the clypeus apically has a strong lateral tooth above the middle of the mandible, medially depressed and similar to labrum, margin sinuate) and females with clypeus large, convex with apical margin laterally angulate, emarginating inwards and medially produced into a blunt lobe (in M. johni the clypeus is large and convex with the apical margin rounded).

Female. ( Figs 1–10 )

Description. Length, 6.1–11.5 mm; fore wing length 3.9–8.9 mm. Black, matte with following parts as follows: antennal segments honey brown; clypeus pale yellowish with apical margin darker; mandibles paler with tooth dark reddish brown to black; lateral edge of pronotum pale yellowish; all tergites with yellow patches or marking postero-laterally, emarginating inwards medially; S3–S6 with yellow patches postero-laterally; all legs orange brown.

Pubescence. Upper frons with small dense golden setae till the anterior margin of toruli ( Fig. 3 ); vertex and gena with dense silvery pubescence, a bare patch adjoining anterior margin of eyes ( Fig. 2 ); clypeus with silvery pubescence and 16–20 brown lanceolate setae; frons and vertex with long thick brown lanceolate setae, variable in number; mesosoma with scattered lanceolate brown setae, dense golden pubescence and long golden hairs, lanceolate setae fewer on mesoscutum; metasoma with dense golden yellow to white pubescence.

Head. A trifle wider than high in frontal view; minutely rugose punctate, punctures hardly visible over dense short golden pubescence; toruli situated little above ventral eye margin, strongly converging ventrally; a thin almost indistinct furrow in between the toruli extending till the clypeal shield ventrally; eyes reniform, converging ventrally, bare, 3.4× as long as wide; lateral ocelli forming an almost right angle with the median ocelli; OOL 1.3× POL; AOD 0.6× POL; head narrowed behind eyes; antennae slender; F1 0.9× scape and pedicel combined, 1.1× as long as F2 ( Fig. 2 ); mandibles strong with an inner subapical tooth; labial brush distinct ( Fig. 5 ); clypeus large, convex with apical margin laterally angulate, emarginating inwards and medially produced into a blunt lobe ( Fig. 4 ); gena slightly narrower than eye in lateral view; occiput carinate throughout.

Mesosoma. Pronotum and propodeum laterally rounded; pronotum posteriorly slightly angulating medially ( Fig. 7 ); scutellum 0.8× mesoscutum in dorsal view ( Fig. 6 ); metapleura striate, smooth anteriorly; foretibia with a single spur apically, all other with two spurs; metatibia with hind basitarsus 0.67× hind tibia, 0.4× hindtarsus combined; tarsal claw with a strong inner curved tooth at apical third; orbicula with a row of thin long setae; fore wing and hind wing with distinct antefurcal nervellus; fore wing with a curving infuscate band at apical third, apex bare; a small obsolete patch near pterostigma ( Fig. 8 ).

Metasoma. Petiole stout; metasoma distinctly longer than mesosoma, a trifle longer than hind femora; T2 longest ( Fig. 9 ), sculpture barely visible through the pubescence on the tergites; S1 with a medial line of white pubescence; S2 anteriorly microsculptured, posteriorly smooth; S2 to S6 micropitted, S2 onwards with lateral yellow marking; S6 with moderately dense long brown setae ( Fig. 10 ); ovipositor and ovipositor sheath not exerted.

Male. ( Figs 11–20 )

Description. Body length 3.7–4.1 mm, fore wing 2.4–2.9 mm. Black, no yellow patches on gastral terga.

Pubescence. Reduced pubescence when compared with the females. Lower face with moderate white setae reaching the clypeal margin; pronotum and mesoscutum sparsely setose; propodeum with long and moderately dense setae concentrated more on the lateral sides.

Head. 1.2× as wide as long in frontal view; finely to minutely colliculate; OOL 1.2× OOL; AOD 0.6× POL; antennal toruli converging posteriorly, a median furrow distinct in between the toruli ( Fig. 13 ); F1 as long as scape and pedicel combined ( Fig. 12 ); eyes reniform; clypeus with lateral edges produced and medially weakly inwardly emarginated, margins carinate ( Fig. 14 ).

Mesosoma. Pronotum, mesoscutum and scutellum rugose punctate with lesser pubescence as that in females; mesoscutum and scutellum finely rugose punctate, mesoscutal margins distinctly carinate laterally; axillae transverse striate; an excavated polished area posterior to tegulae ( Fig. 15 ); propodeum with irregular areola; some specimen with long hairs on mesosoma ( Fig. 16 ); all coxae black; other segments honey brown with darker shades; wing venation similar to that of females, no distinct band, but with lighter infuscation apically ( Fig. 17 ).

Metasoma. Metasoma as long as mesosoma without any yellow markings ( Fig. 18 ); S1 smooth, shiny with scattered setae postero-laterally; S2 minutely microsculptured; S3 onwards alutaceous and moderately setose; hypopygium with a median protubrence, emarginating submedially ( Fig. 19 ); genitalia with gonostyli long, strongly setose and with a basal spiniform process in lateral view ( Fig. 20 ).

Prey. Spiders of the family Salticidae . Remains of spiders were recovered from nests also.

Etymology. The species epithet is derived from the family name of the wasp’s prey.

Distribution. India: Kerala.

Sex association. Sex differentiation is formidable in the overall colouration and setosity of the body. The males were found hovering over the unopened nest cells, maybe as a behavioural mechanism to mate with the emerging females. Emergence of both males and females in large numbers from the same batches of nests (n>20) in similar habitats, along with similar modes of parasitism on spiders within the nests, supports the association of the sexes.

Figures

FIGURES 1–8. Machaerothrix salticidus Binoy, Girish Kumar andAnju sp. nov. Holotype, ♀. 1. Habitus, lateral view. 2. Head and antenna, lateral view. 3. Head, frontal view. 4. Clypeus. 5. Head, ventral view (labial brush). 6. Mesosoma, dorsal view. 7. Propodeum, dorsal view. 8. Fore wing. Scale bar: 1– 2 mm; 2, 6, 8– 1 mm; 3, 7– 0.5 mm; 4, 5– 0.2 mm.

FIGURES 9–10. Machaerothrix salticidus Binoy, Girish Kumar and Anju sp. nov. Holotype, ♀. 9. Metasoma, dorsal view. 10. Metasoma, ventral view. Scale bar: 9, 10– 1 mm.

FIGURES 11–18. Machaerothrix salticidus Binoy, Girish Kumar & Anju sp. nov. Paratype, ♂. 11. Habitus, lateral view. 12. Head and antenna, lateral view. 13. Head, frontal view. 14. Clypeus. 15. Mesosoma, dorsal view. 16. Propodeum, dorsal view. 17. Fore wing. 18. Metasoma, dorsal view. Scale bar: 11– 2 mm; 12, 15, 17– 1 mm; 13,18– 0.5 mm; 14, 16– 0.2 mm.

FIGURES 19–20. Machaerothrix salticidus Binoy, Girish Kumar & Anju sp. nov. Paratype, ♂. 19. Hypopygium, in ventral view. 20. Genitalia, in lateral view. Scale bar: 19, 20– 0.2 mm.