Ammoplanellus keralaensis Tessy, Girish Kumar & Sureshan, 2024

Rajan, Tessy, Kumar, P. Girish, Sureshan, P. M. & Hegde, V. D., 2024, A review of the genus Ammoplanellus Gussakovskij (Hymenoptera: Crabronidae: Pemphredoninae) from India with the description of two new species, Zootaxa 5477 (1), pp. 73-80 : 75-77

1. Ammoplanellus keralaensis Tessy, Girish Kumar & Sureshan sp. nov. ( Figs 1–8 )

Type material: Holotype, f#, India: Kerala, Kannur district, Kannapuram (11°58’ 8.76’’N, 75°19’14.88’’E, 9 m), 3.iii.2019, C. Charesh collector, ZSIK Regd. No. ZSI/ WGRC /IR/INV/20873.

Diagnosis. Ammoplanellus keralaensis sp. nov. differs from its congeners by the following combination of characters: head and mesosoma black; mesoscutum irregularly transversely striate; posterior surface of propodeum irregularly transversely striate and with a median carina.

Description. Holotype f#. Body length 2.0 mm.

Colour. Head and thorax black. Following parts yellow: flagellum beneath except brown towards apex; legs except coxae, femora and tibiae brown. Pterostigma bicolorous, dark in distal half. Pronotal lobe white ( Fig. 1 ).

Head. Lower face medially depressed, irregularly reticulate. Vertex inconspicuously striate. Inner eye orbits concave. Lower ends of eyes not conspicuously produced towards torulus. Torulus placed 0.02 mm above the clypeal margin. Distance between toruli 0.04 mm and distance between torulus and eye 0.03 mm. Head width 0.41 mm in frontal view. Distance from top of head to tip of clypeus 0.35 mm in frontal view. Frons width 0.28 mm at middle of inner eye margin. Distance between lower ends of eyes 0.19 mm. Length of scape and pedicel 0.13 mm and 0.04 mm, respectively. Scape distinctly long and not narrow. Pedicel as long as two following flagellomeres combined. Flagellum clavate, proximal flagellomeres subquadrate, bearing very distinct erect setae. Clypeus smooth, broadly reaching lower eye orbit. Clypeal margin protruding medially, not emarginate. Labrum produced into two stout teeth but without trace of median tooth. Mandibles of usual shape ( Fig. 2 ). Occipital carina well developed.

Mesosoma. Pronotum rather narrow, collar rounded and short, dull, finely transversely striate. Mesoscutum irregularly transversely striate, punctures hardly traceable. Scutellum smooth, anteriorly with deep crenulate groove ( Fig. 3 ). Metanotum smooth in middle, laterally with longitudinal rugae. Mesopleuron convex and for most part smooth, inconspicuously striato-reticulate ( Fig. 4 ). Propodeal dorsum areolate-rugose. Posterior surface of propodeum irregularly transversely striate and with median carina ( Fig. 5 ). Forewing with anteriorly open marginal cell ( Fig. 6 ).

Metasoma. Terga smooth and shiny, with a few inconspicuous transverse striae. Pygidial plate broad, surface slightly irregularly reticulate and with sparse setigerous punctures ( Fig. 8 ).

Male. Unknown.

Etymology. The specific epithet ‘ keralaensis’ is derived from the name of the Indian state of Kerala, where the type specimen of this species was collected. It is the only Ammoplanellus collected so far from this state and thus serves as a unique representation of its biodiversity.

Distribution. India: Kerala.

Discussion. This new species differs from the only species reported from the Oriental region, viz., Ammoplanellus simplex Gussakovskij, 1952 ( India: New Delhi) by Bouček (2001) as follows.

(1) marginal cell anteriorly open, its enclosing vein not reaching anterior wing margin (in A. simplex , marginal cell closed or almost closed, enclosing vein antero-distally, often very pale and sometimes only its inner margin traceable); (2) toruli and lower ocular line are in same level (in A. simplex , toruli placed distinctly above lower ocular line); (3) and face black (in A. simplex , face extensively white or pale yellow).

This new species differs from Ammoplanellus hissaricus Gussakovskij, 1952 , which resembled the unnamed species collected by Bouček (2001) from India (“ Delhi, Agra”) as follows.

(1) the marginal cell anteriorly open, its enclosing vein not reaching the wing anterior margin (in A. hissaricus , the marginal cell is closed or almost closed, enclosing vein antero-distally, often very pale and sometimes only its inner margin traceable); (2) toruli and lower ocular line are in same level (in A. hissaricus , toruli placed distinctly above lower ocular line; (3) clypeal margin protruding medially, not emarginated (in A. hissaricus , anterior margin of clypeus medially emarginated; clypeal median margin narrowly U-shaped); (4) clypeal side narrowly or barely reaching eye orbit at upper condyle of mandible (in A. hissaricus , clypeal side not reaching eye orbit at upper condyle of mandible); (5) metasoma not distinctly petiolate (in A. hissaricus , metasoma distinctly petiolate); and (6) face black (in A. hissaricus , face entirely or in lower two-thirds extensively yellow).

In Bouček’s key to Palearctic Ammoplanus (2001), this new species comes close to the couplet 64, i.e., to Ammoplanellus chorasmius Gussakovskij, 1931 and Ammoplanellus rhodesianus Arnold, 1924 .

A. keralaensis distinctly differs from A. chorasmius in having: (1) eyes not much produced towards torulus (in A. chorasmius , eyes distinctly produced towards torulus); (2) mesoscutum irregularly striato-reticulate (in A. chorasmius , mesoscutum finely transversely striate); (3) scape distinctly long and not narrow (in A. chorasmius , scape short and narrow); and (4) dorsal side of propodeum areolate rugose (in A. chorasmius , dorsal side of propodeum very coarsely and rather irregularly alveolate).

A. keralaensis differs from A. rhodesianus by the following key characters provided by Bouček (2001) (1) mesoscutum irregularly striato-reticulate (in A. rhodesianus , mesoscutum densely and almost regularly polygonally reticulate); (2) proximal flagellomeres subquadrate (in A. rhodesianus , proximal flagellomeres elongate).

Figures

FIGURES 1–8. Ammoplanellus keralaensis Tessy, Girish Kumar & Sureshan sp. nov., Holotype f#. 1. Habitus, lateral view; 2. Head, frontal view; 3. Head and mesosoma, dorsal view; 4. Mesosoma, lateral view; 5. Mesosoma, dorsal view; 6. Fore wing; 7. Fore wing; 8. Metasoma, dorsal view.