Gigascolia speciosissima Castagnet & Cabon, 2025

Gigascolia speciosissima Castagnet & Cabon , sp. nov.

https://zoobank.org/NomenclaturalActs/ 53C13AF6-44F9-44DF-8FFF-C815D799665B

( Figs 7 View FIGURE 7 , 13 View FIGURE 13 )

Type material. Holotype (CCEC), ♀,[red labels]“ INDONESIA. South / Sulawesi pr., Palopo / Buntu Karanganlotong / XII.2017 / Local collector leg.”, “ HOLOTYPE ♀ / Gigascolia / speciosissima / Castagnet & Cabon, 2025 ”.

Diagnosis. Gigascolia speciosissima Castagnet & Cabon , sp. nov. differs from G. speciosa (Smith, 1858) in females by having the apical margin of clypeus with a prominent median lobe; the dorso-median area of propodeum almost entirely punctate; and the T1 largely punctate medially. In contrast, in G. speciosa the apical margin of clypeus is straight, without a prominent median lobe; the dorso-median area of propodeum is almost impunctate; and the T1 is largely impunctate medially. The male of G. speciosissima is unknown.

Description of the holotype, female ( Fig. 13 View FIGURE 13 ). Length 37 mm.

Head ( Figs 13B, C View FIGURE 13 ). Anterior edge of clypeus with prominent median lobe. Disk of clypeus slightly domed in the middle, very finely and densely punctate laterally; impunctate medially; very densely and finely punctate apically, bearing long dense setae. Fissura frontalis weak but distinct, reaching the level of the lamina frontalis and ending in a deep pit. Frons impunctate. Vertex impunctate; sparse punctures at median ocelli, forming a line stopping well before the eyes.

Mesosoma ( Fig. 13D View FIGURE 13 ). Pronotum very finely and densely punctate basally; largely impunctate on the rest, except the region close to the tegula with coarse, sparse punctures. Tegula largely impunctate; near scutum densely and finely punctate; medially with about ten coarse punctures. Scutum with fine, sparse and irregular punctures basally; largely impunctate laterally, medially and apically. Scutellum with fine and dense punctures over most of its surface. Metanotum with very fine and dense punctures all over. Dorso-lateral area of propodeum with an impunctate area (mirror); the rest with fine and very dense punctures. Dorso-median area of propodeum densely and coarsely punctate. Mesopleura densely and finely punctate with long, dense setae. Anterior part of upper plate of metapleure densely and coarsely punctate on anterior two-thirds, impunctate on posterior third. Lower plate of metapleure densely and coarsely punctate all over. Second transverso-cubital vein arrives well after the junction between the first transverso-cubital vein and the radial area.

Metasoma ( Fig. 13E View FIGURE 13 ). T1 very densely and finely punctate apically; more coarsely and densely punctate laterally, basally and medially. T2 with fine and dense punctures basally and apically; mostly impunctate medially, with coarse and dense punctures. T3 with dense, coarse punctures basally; impunctate medially; finely and densely punctate apically. T4 and T5 with similar punctures. Hypopygidium coarsely and densely punctate, except medially with impunctate area. S1 impunctate basally, domed and very densely and finely punctate apically. S2 with a slight tubercle, finely and densely punctate; with coarse punctures basally and medially; apical part densely and finely punctate laterally, with coarse and sparse punctures in the middle. S3 to S5 with similar punctures.

Coloration ( Fig. 13 View FIGURE 13 ). Head black, with two vertical yellow stripes running from the frons to the vertex and interrupted several times. Antennae black. Mesosoma and metasoma entirely black. Legs black. Wings entirely dark, with violet-blue reflections. Pilosity entirely black.

Male. Unknown.

Distribution. Indonesia ( South Sulawesi) ( Fig. 7 View FIGURE 7 ).

Biology. Unknown.

Etymology. The specific epithet speciosissima is the superlative form of the Latin word speciosa , which means “beautiful”. As Smith noted when describing Scolia speciosa , Gigascolia speciosissima , sp. nov. is for us the most beautiful species of the newly created genus.

Genus Megascolia Betrem, 1928

( Figs 1C, 2C View FIGURES 1–2 , 3B, 4B, 5B View FIGURES 3–6. 3–5 , 14–30 View FIGURE 14 View FIGURE 15 View FIGURE 16 View FIGURES 17–18 View FIGURE 19 View FIGURE 20 View FIGURE 21 View FIGURE 22 View FIGURE 23 View FIGURE 24 View FIGURE 25 View FIGURE 26 View FIGURE 27 View FIGURE 28 View FIGURE 29 View FIGURE 30 )

Scolia ( Triscolia) Saussure, 1863: 17 ; Saussure & Sichel 1864: 38; Rohwer 1921: 77; Betrem 1927a: xcvii.

Triscolia : Gribodo 1893: 150; Micha 1927: 79.

Scolia View in CoL ( Triscolia sectio Megascolia ) Betrem, 1928: 239; Betrem 1933: 255.

Megascolia : Bradley & Betrem 1964: 437; Petersen 1970: 64; Argman 1996: 199; Osten 2001: 439; Gupta & Jonathan 2003: 132, 133; Osten 2005b: 26; Taylor 2024a: 995; Taylor 2024b: 120; Golfetti et al. 2025: 3, 10, 13; Barthélémy & Guenard 2025: 105.

Type species. Scolia procer Illiger, 1802 , by original designation.

Species included. Three species: Megascolia procer ( Illiger, 1802) , M. scutellaris ( Gribodo, 1893) , and M. velutina ( Saussure, 1859) .

Diagnosis. Megascolia Betrem, 1928 is distinguished from the genus Gigascolia Castagnet & Cabon , gen. nov. and Regiscolia Betrem & Bradley, 1964 , stat. nov. in both sexes by having the dorso-median area of propodeum sloping posteriorly, with an indistinct transition to the postero-median area; and the latero-tergal area of T3 without groove. In Gigascolia gen. nov. and Regiscolia stat. nov., the dorso-median area of propodeum is flat, with a distinct transition to the postero-median area, forming a ridge; and the latero-tergal area of T3 has a groove crossing the entire sclera.

Furthermore, in females of Megascolia , the pronotum has a more or less prominent tubercle in front of the tegula; the hind basitarsus does not have scopa; and the apex of hind basitarsus is bordered by a dense row of spines of similar size. Whereas females of Gigascolia gen. nov. and Regiscolia stat. nov. have the pronotum without tubercle in front of the tegula; the hind basitarsus with a scopa on the inner extremity; and the apex of hind basitarsus bordered by a row of spines of very unequal size. In males of Megascolia , the antennal segments are long, segment III of antenna 2 to 2.2 times longer than wide; and scutum 1.1 to 1.2 times wider than long. Whereas in Gigascolia gen. nov. and Regiscolia stat. nov. the antennal segments are shorter, the segment III of antenna is 1.4 to 1.8 times longer than wide; and the scutum is 1.4 to 1.5 times wider than long.

Redescription. Female. Mandibles with two teeth on its inner margin. Clypeus about twice as long as wide. Anterior margin of clypeus narrower and not broadly truncated in median part; disk of clypeus domed in the middle, usually entirely punctate; without fringe of dense setae apically. Lamina frontalis strong, elevated and densely punctate at the level of the frontal spatium. Frontal area forming an elongated isosceles triangle. Frons and vertex almost impunctate; if present, punctures are fine and very sparse. Rounded head, longer than it is wide. Mesosoma clearly longer than wide. Pronotum with tubercle in front of tegula. Callosity of pronotum without vertical carina. Scutum almost as long as wide. Dorso-median area of propodeum as long as wide, strongly sloping posteriorly, transition to postero-median area indistinct; depressed relative to the dorso-lateral areas of propodeum. Coxae III elongated, without prominent tubercle on inner surface. Hind metatarsus without scopa at the inner end; the apex bordered by a dense row of spines of similar size. Forewing with three submarginal cells. Second transverso-cubital vein arrives well after the junction between the first transverso-cubital vein and the radial area. T1 with a tubercle, without vertical transverse suture; campaniform, gradually widening. Apical margin of basal tergites with tight, fine punctures and long, dense pilosity forming a band. Lateral-tergal area of T3 without groove. S1 long, flat and sparsely punctate.

Male. Inner margin of mandible with three distinct tooth (third apical tooth sometimes blunt and barely visible). Antennal articles long; segment III of antenna 2 to 2.2 times longer than wide. Frontal area irregularly pentagonal with acute apex. Mesosoma distinctly longer than wide. Scutum 1.1 to 1.2 times wider than long. Dorso-median area of propodeum steeply sloping posteriorly, transition to postero-median surface indistinct; depressed relative to the dorso-lateral areas of propodeum. Dorso-median and dorso-lateral areas densely and finely punctate, sometimes with a small impunctate surface. T1 usually with strong, blunt tubercle, without vertical transverse groove. Laterolateral area of T3 without furrow, with fine, dense punctures. S1 flat and sparsely punctate.

Genitalia ( Fig. 15 View FIGURE 15 ). Gonocoxites forming two sclerotized half-rings that touch in the middle on the ventral side and at the base on the dorsal side. Ventral part of each gonocoxite subrectangular, obliquely arranged; dorsal part larger, slightly swollen. Side of each gonocoxite extended by an elongated gonostyle, narrow at the base and progressively widened towards the apex, the latter subtruncate. Gonostyle with numerous setae; outer lateral setae, present over three-quarters of gonostyle length, brown, very long and curved at tip; setae on medial side and apical setae fine and shorter.

Volsella with a wide basal part and an elongated distal part (about 2-3 times as high as wide), with parallel edges, rounded at the apex. Basal part with a rather indistinct, rounded distal lobe on the lateral (outer) side. Basal and distal parts of volsella separated by a simple angulation, not a notch. Ventral side of basal part of volsella with about twenty long, fine setae. Apex of distal part with a tight group of strong brown setae, more or less long and curved, forming a characteristic bouquet. Brown sensory conules, 25 to 50 μm long, present at different levels of the volsella: two short, closely spaced conules (difficult to observe) at the tip of the lateral lobe of the basal part; numerous similar conules, but slightly longer and close together, along the lateral edge of the volsella, in its middle part; two groups of two or three conules in a more distal position.

Aedeagus reaching or slightly exceeding gonostyles in length. Sclerified penile valves joined by membrane, which forms a rounded cap at the apex of the aedeagus. Penile valves in lateral view with a wide distal part, truncated at the tip, followed by a narrowed middle part, then an even narrower basal part. Ventral edge of distal part with a row of 8 to 10 sclerotized teeth, particularly long (0.2 to 0.4 mm) and pointed; middle teeth longer than teeth at both ends, forming a curved line.

Distribution. China ( Yunnan; new record), India ( Arunachal Pradesh), Indonesia ( Bengkulu, Central Sulawesi, Gorontalo, East Java, East Kalimantan, Jakarta, Lampung, Jambi, Maluku, North Malaku, North Sulawesi, North Sumatra, South Sulawesi, South Sumatra, Southwest Papua, West Java, West Kalimantan, West Sumatra), Laos (Oudoxmay; new record), Malaysia ( Pahang, Perak, Phatthalung, Sabah, Sarawak, Selangor), Myanmar, The Philippines ( Agusan del Sur, Bukidnon, Battan, Cagayan, Cotabato, Davao del Sur, Laguna, Lanao del Sur, Misamis, Negros Occidental, Oriental Mindoro, Palawan, Quezon, Samar, Sarangani, Surigao del Sur, Zamboanga del Norte), Singapore, Thailand, Vietnam ( Saussure & Sichel 1864; Gribodo 1893; Cameron 1901; Mantero 1903; Rohwer 1921; Micha 1927; Betrem 1928; Betrem & Bradley 1964; Gupta & Jonathan 2003; Ming & Soh 2020) ( Fig. 14 View FIGURE 14 ).

Key to species of Megascolia Betrem, 1928

Females

1. Pronotum with a blunt, inconspicuous tubercle in front of the tegula. Scutellum and metanotum densely punctate ( Fig. 16A View FIGURE 16 ). Entirely black, sometimes with yellow markings mainly on vertex............................. M. velutina (Saussure)

- Pronotum with a prominent tubercle, clearly visible in front of the tegula. Scutellum and metanotum sparsely punctate ( Figs 16B, C View FIGURE 16 ). Vertex, scutellum, metanotum marked yellow, sometimes also T1 and T3.................................. 2

2. Pronotum largely impunctate medially and apically; with prominent tubercle in front of the tegula ( Fig. 16B View FIGURE 16 ). Scutum densely and more coarsely punctate basally ( Fig. 16B View FIGURE 16 ). Apical end of hind femur bearing a row of spines. T1 with a large impunctate area basally and medially. Frons and generally T1 and T3 marked with yellow....................... M. procer (Illiger)

- Pronotum more densely punctate all over, without large impunctate areas; with a tooth-like tubercle in front of the tegula ( Fig. 16C View FIGURE 16 ). Scutum very densely and finely punctate basally ( Fig. 16C View FIGURE 16 ). Apical end of hind femur bearing dense tuft of bristles, without spines. T1 largely punctate, basally and medially more sparsely and coarsely punctate with a small impunctate area. Frons, T1 and T3 black.............................................................. M. scutellaris (Gribodo)

Males

1. Frons largely impunctate in front of median ocelli ( Fig. 17A View FIGURES 17–18 ). Pronotum finely and sparsely punctate, with a largely impunctate area in front of the tegula ( Fig. 18A View FIGURES 17–18 ). Tegula with a few coarse punctures apically, the rest with micro-punctures. Scutum largely impunctate medially ( Fig. 18A View FIGURES 17–18 ). Dorso-median area of propodeum with less dense punctures, inter-point spaces about equal to the diameter of a puncture. T1 with a large impunctate area basally. Clypeus, frons, vertex, pronotum, scutellum, metanotum, T1 and T3 generally marked with yellow..................................................... M. procer (Illiger)

- Frons densely punctate ( Figs 17B, C View FIGURES 17–18 ). Pronotum densely and finely punctate all over ( Figs 18B, C View FIGURES 17–18 ). Tegula coarsely and densely punctate over most of its surface, the rest with micro-punctures. Scutum densely punctate all over ( Figs 18B, C View FIGURES 17–18 ). Dorso-median area of propodeum with denser punctures, inter-point space much smaller than the diameter of a puncture. T1 largely punctate, basally with more sparse and coarse punctures. Entirely black or only the scutellum and metanotum marked with yellow... 2

2. Scutum basally, with extremely fine, dense, coalescent punctures; pilosity long and thick ( Fig. 18B View FIGURES 17–18 ). Scutellum and metanotum sparsely and coarsely punctate ( Fig. 18B View FIGURES 17–18 ). Black, scutellum and metanotum marked with yellow... M. scutellaris (Gribodo)

- Scutum basally, with distinctly coarser, dense, sometimes coalescent punctures; pilosity shorter and finer ( Fig. 18C View FIGURES 17–18 ). Scutellum and metanotum densely and finely punctate ( Fig. 18C View FIGURES 17–18 ). Entirely black.......................... M. velutina (Saussure)