Arkaditilla gibba, Okayasu, 2021

Okayasu, Juriya, 2021, A new velvet ant genus Arkaditilla (Hymenoptera, Mutillidae, Trogaspidiini) from the Oriental Region, with review of species, Journal of Hymenoptera Research 84, pp. 145-168 : 145

publication ID	https://dx.doi.org/10.3897/jhr.84.68709
publication LSID	lsid:zoobank.org:pub:5F83EC63-7C79-47FD-BD29-E7A2B9328518
persistent identifier	https://treatment.plazi.org/id/25D8F0E2-795C-4BC7-BDAB-461B910EE8A9
taxon LSID	lsid:zoobank.org:act:25D8F0E2-795C-4BC7-BDAB-461B910EE8A9
treatment provided by	Journal of Hymenoptera Research by Pensoft
scientific name	Arkaditilla gibba
status	sp. nov.

Treatment

Arkaditilla gibba sp. nov.

Figures 7 View Figures 7–12 , 8 View Figures 7–12 , 16 View Figures 13–18 , 22 View Figures 19–36 , 31 View Figures 19–36 , 32 View Figures 19–36 , 43 View Figures 37–48 , 44 View Figures 37–48 , 58-60 View Figures 49–66 , 70 View Figures 67–72 , 75 View Figure 73–76

Diagnosis.

Male. Clypeus medially strongly elevated even ventrally. Mandible with sharp subapical and large inner subbasal teeth (Fig. 16 View Figures 13–18 ), ventrally deeply excised with large basal tooth (Fig. 22 View Figures 19–36 ). Scape ventral carinae divergent apically (Fig. 31 View Figures 19–36 ), densely punctate between them; F1 apical 1/3 and F2 whitish yellow on ventral half; F1 strongly depressed, F1 height ~0.8 × pedicel diameter (Fig. 32 View Figures 19–36 ). T3 orange (Fig. 8 View Figures 7–12 ); cuspis widened near apex, forming oblique posterior margin (Figs 58 View Figures 49–66 , 70 View Figures 67–72 ); digitus posteriorly expanded, forming triangular projection (Fig. 43 View Figures 37–48 ); paracuspis slightly tuberculate (Fig. 70 View Figures 67–72 ); penis valve weakly expanded ventrally (Figs 59 View Figures 49–66 , 60 View Figures 49–66 ). Female. Unknown.

Description.

Male. Body length: 12.4-15.1 mm (holotype: 12.4 mm; mean: 13.8 mm); forewing length: 10.6-11.0 mm (holotype: 10.6 mm; mean: 10.8 mm).

Color and setae. Frons, vertex, gena, clypeus, mandible mostly, scape, pedicel, flagellum mostly, prementum, stipes, mesosoma, coxae, femora, tibiae, tarsi, T4-T7, S1 medial carina, S4-S8 black; mandible medial 1/4 reddish brown; F1 apical 1/3, F2 whitish yellow on ventral half; labrum, tegula brownish black; trochanters, protibial spur dark brown; meso- and metatibial spurs pale yellow; T1-T3, S1 except medial carina, S2-S3 orange; wings pale brown, with veins dark brown. Upper frons, vertex, T1, S1 with sparse long erect pale golden setae; lower frons, pronotal dorsum, dorsal propodeal face, dorsal half of lateral propodeal face with dense short appressed and sparse long erect pale golden setae; gena, femora, tibiae with sparse short recumbent and sparse long erect pale golden setae; eye dorsal margin with long erect black setae; clypeus with dense long recumbent pale golden setae; mandible, trochanters, T2 lateral margin with sparse long recumbent pale golden setae; scape with sparse long recumbent and sparse long erect pale golden setae; pedicel, F1 with sparse short recumbent pale golden setae; F2-F11 with sparse erect pale golden microsetae; pronotal collar anteriorly, T2 disc, T3-T5, S3-S6 with sparse short erect pale golden setae; pronotal collar posteriorly glabrous; pronotal lateral face, coxae with sparse long appressed pale golden setae; propleuron with sparse long appressed and sparse long erect pale golden setae; mesoscutum with sparse short recumbent and sparse short erect goldish black setae; mesoscutellum, metascutellum with sparse short recumbent pale golden and sparse long erect pale golden to blackish golden setae; axilla, metanotal trough with dense long appressed pale golden setae; anterior and posterior parts of mesopleuron, metapleuron, ventral half of lateral propodeal face with sparse short appressed pale golden setae; medial and ventral parts of mesopleuron with dense long appressed and sparse long erect pale golden setae; tegula anterior portion, tarsi with sparse long recumbent pale golden setae; tegula inner margin with sparse short recumbent and sparse short erect golden setae; S2 with sparse short recumbent and sparse short erect pale golden setae; T6-T7, S7-S8 with sparse short erect black setae; T2 with lateral golden felt line; T1-T5, S2-S5 with posterior fringe of sparse pale golden setae; S6-S8 with posterior fringe of sparse black setae.

Structure. Head 1.89-1.92 × as wide as long (holotype: 1.92); lateral margins strongly convergent behind eye; vertex rounded posteriorly; POD/OOD = 0.56-0.77 (holotype: 0.77); OD:MOD:LOD = 1.00:1.15-1.58:0.92-1.08 (holotype: 1.00:1.58:0.92); ocellar region slightly convex, ocelli without posterior carina; antennal scrobe with weak inverted V-shaped dorsal carina not reaching inner eye margin; genal carina absent; postgenal bridge flattened; hypostomal carina weakly developed; clypeus medially strongly elevated even ventrally, without subventral transverse groove; anterior clypeal margin projecting medially; mandible robust, narrowed to apex with inner margin expanded forming large subbasal tooth; mandible apex bidentate; mandible ventral margin excised into large basal tooth; mandible dorsal carina sharp; prementum flattened; scape curved medially, with two longitudinal ventral carinae divergent apically; F1 depressed, F1 height 0.75 × pedicel diameter; relative length of pedicel, F1 and F2 = 1.00:3.00-3.05:1.84-2.26 (holotype: 1.00: 3.05:1.84); F2-F11 almost equal in width; F11 as long as F2, conical.

Mesosoma widest at mesonotum including tegulae; head width:humeral width:pronotal width:mesonotal width = 87:60:93:100; humeral angle rounded, with sharp humeral carina not reaching pronotal dorsum; mesoscutum strongly convex; mesoscutal width 1.20 × its length; tegula short rounded, posteriorly reaching mesoscuto-scutellar articulation, 1.43-1.44 × as long as wide (holotype: 1.44); notaulus evenly wide, reaching anterior 1/2 of mesoscutum, subparallel; parapsidal line length 0.25 × mesoscutal length; parascutal carina forming rounded, weakly elevated process on postero-lateral angle of mesoscutum; mesoscutellum convex without medial carina, tubercle or impunctate line; mesopleuron divided into dorsal and ventral convexities by distinct transverse mesopleural groove, ventrally without transverse precoxal ridge, longitudinal impunctate line, or precoxal swelling; dorsal propodeal face without distinct dorsum and sublateral carina, with anterior inverted triangular cell and semicircular sublateral cell; lateral margins of propodeum gradually convergent posteriorly; dorsal and lateral propodeal faces not separated by carina.

Wings well developed; distance between origin of RS on vein SC and base of stigmatic cell equal to stigmatic cell length and first abscissa of RS length; cell 2RS present.

Meso- and metacoxae evenly convex; metacoxa with weak complete inner longitudinal carina; protibial spur slender; tibiae without outer spines.

T1 without distinct dorsum; T1 spiracle weakly tuberculate; T2 evenly convex, 1.25 × as wide as long; S1 with straight medial longitudinal carina with its ventral margin convex; S2 swollen anteriorly; T7 medially with longitudinal impunctate convex line, posteriorly not forming tubercle; S6-S8 without lateral carina or tubercle; S7 entirely exposed, 0.75 × as long as S8; S8 mostly sclerotized with posterior membranous area evenly convex posteriorly. Paramere down-curved posteriorly, with weak inner protuberance on posterior 1/2 of dorso-inner margin; inner margin of paramere dorsally with short erect golden setae; ventral lobe posteriorly projecting, pointed; parapenial lobe large, with posterior margin concave; cuspis long slender, widened near apex, forming oblique posterior margin, apparently surpassing apex of penis valve, with dense long erect setae ventrally and posteriorly; digitus straight, posteriorly expanded, forming triangular projection, with dense erect golden setae posteriorly; paracuspis slightly tuberculate with few erect golden setae; penis valves symmetrical slender, weakly expanded ventrally, with posterior ventral hook, without setae.

Frons, vertex, gena, pronotal dorsum, mesoscutum, medial part of mesopleuron with large dense punctures; postgenal bridge, trochanters, femora, tibiae, T1 medially, T2 disc, S2 with small sparse punctures; clypeus lateral portion, mandible outer and dorsal faces, scape between ventral carinae, flagellum, pronotal lateral face, propleuron, axilla, metanotal trough, anterior and posterior parts of mesopleuron, metapleuron, ventral half of lateral propodeal face, coxae, tarsi with minute dense punctures; clypeus medial convexity, scape mostly, pedicel, T1-T2 laterally, T3-T7, S1, S3-S8 with small dense punctures; mesoscutellum with large confluent punctures; metascutellum with small confluent punctures; dorsal propodeal face, dorsal half of lateral propodeal face reticulate; pronotal collar anteriorly with minute sparse punctures; pronotal collar posteriorly smooth; tegula mostly microreticulate with few small punctures anteriorly, postero-inner portion with minute sparse punctures.

Type material.

2♂. Holotype ♂: Indonesia: East Java: Mt. Argopuro, 31.VII.1995 [TKPM]. Paratype: Indonesia: East Java: Mt. Argopuro, 31.VII.1995 [1♂ TKPM].

Distribution.

Indonesia: East Java.

Etymology.

The specific name Arkaditilla gibba is a Latin noun meaning gibbosity. It refers to the strongly elevated clypeus of this new species.

Remarks.

This species and A. nallinia are recognized in Arkaditilla by having the mandible with sharp subapical and large inner subbasal teeth, the mandible ventral margin deeply excised with large basal tooth, the scape ventral carinae divergent apically, F1 strongly depressed, the cuspis widened posteriorly, the digitus posteriorly expanded, the paracuspis tuberculate, and the penis valve weakly expanded ventrally, but the former differs from the latter by having the clypeus strongly elevated even ventrally (clypeus elevated dorsally in A. nallinia ), and the cuspis widened near apex (cuspis widened on posterior 1/3 in A. nallinia ).