Amegilla ( Glossamegilla ) celineae Carion, 2025

Carion, Frédéric, Gérard, Maxence, Ghisbain, Guillaume & Wood, Thomas J., 2025, Unravelling Amegilla (Glossamegilla) diversity across the Wallace Line: new species, wing morphometrics, and biogeographic boundaries (Hymenoptera, Apidae), ZooKeys 1256, pp. 1-79 : 1-79

Amegilla ( Glossamegilla) celineae Carion sp. nov.

Fig. 8

Type material.

Holotype: Indonesia • ♀; S. Borneo [ East Kalimantan], Gn. Pandjang, Tanggarang [Gunung Panjang] ; 4 Jul. 1937; Mrs. M. E. Walsh leg.; RMNH, RMNH.INS.1713956 .

Diagnosis.

Male: Unknown.

Female: Amegilla celineae sp. nov. is a species without typically contrasting hair bands on T 2-4, except on T 3-4 where the hair bands are slightly more contrasting (but not as much as in the banded species). Amegilla celineae sp. nov. can be differentiated from both colour forms of A. amymone by the pale clypeal mark more extensive, not restricted to a small triangular paler mark at the apex (while A. amymone have pale clypeal marks restricted to a small triangular paler mark at the apex, sometime with a narrow line of the same colour just above) and terga without apricot-orange pubescence (while A. amymone have apricot-orange pubescence on at least T 4-6, sometimes only apically on T 4). Amegilla celineae sp. nov. differs from A. himalajensis (Radoszkowski, 1882) by the pale yellow clypeal marks (while the marks are dark brown in A. himalajensis ) as well as the presence of black hairs intermixed in the pubescence of the mesosoma (while A. himalajensis does not have any black hairs intermixed on the mesosoma). Amegilla celineae sp. nov. can be separated from the trio A. insularis , A. pagdeni Lieftinck, 1956 and A. cinnyris by a more protuberant clypeus, in profile view the clypeus equals or slightly exceeds the width of the compound eye (while the trio have a less protuberant clypeus that in profile view is smaller than the width of the compound eye, sometimes only a bit smaller) and the outside of the basitarsus III without black hairs, entirely covered by pale pubescence (while the trio have a basitarsus III at least partially covered by black pubescence). Amegilla celineae sp. nov. differs from A. vigilans by less extended yellow clypeal marks (while A. vigilans have more extended and momre orangish pale clypeal marks), a brighter pilosity (more bright fulvous to bright orange while A. vigilans is more ochraceous to slightly fulvous), terga entirely and more evenly clothed by fulvous to orange pubescence leading to not very contrasting hair bands at the apex of the terga, except on T 3-4 where the hair bands are more visible (while A. vigilans have the terga entirely clothed with pale ochraceous pubescence that is slightly denser apically, giving slightly contrasting and poorly-defined hair bands, the hair bands on T 3-4 do not contrast more than these on the other terga, hair bands more consistent) as well as hind tibiae orange to pale brown (while A. vigilans have usually dark hind tibiae, neither orange nor pale brown).

Amegilla celineae sp. nov. is therefore morphologically close to A. pendleburyi but differs by the mainly impunctate paraocular areas (only a very punctures visible while A. pendleburyi have entirely punctate paraocular areas), the labrum not entirely and evenly punctate with the presence of two impunctate areas on the sides of the labrum (below the two protuberances) ( A. pendleburyi have a labrum entirely and evenly punctate), punctation of the clypeus coarser with smaller and hardly visible interspaces (while A. pendleburyi have a clypeus with finer punctation and broader well-visible interspaces), a metasoma with a more uneven pubescence and hair bands at the apex of the terga more contrasting (T 3-4 basally covered by a small black haired area) ( A. pendleburyi have a more even pubescence, the terga usually do not have any apical contrasting hair bands) as well as a larger size of ~ 19 mm (while A. pendleburyi is smaller, ~ 18 mm maximum).

Description.

Male: Unknown

Female: Length of 19 mm. Interalar width of ~ 3.8 mm (shorter distance between the base of the tegulae).

Head: Labrum rectangular, wider than long (8: 7, 2.4 × 2.1 mm), with two slightly protruding brownish areas at the base, remaining labrum entirely brownish yellow except for the brown transverse carina at the apex of the labrum. Centre of the labrum punctate with a dense and deep punctation (interspaces of at most the diameter of a punctures but generally smaller). Sides of the labrum less punctate with impunctate areas just below the protuberances of the labrum as wells as a less dense punctation on remaining sides with interspaces of at least the diameter of a puncture (generally larger than this diameter). A band on the centre of the labrum covered by long fulvous setae of approximately the size of the diameter of an ocellus, apex of labrum also covered by a band of (denser) hairs that are of the same colour but smaller. Mandibles not bidentate (bi-dentation not visible) and very blunt, almost square, basal 1 / 2 darkened yellow, other 1 / 2 dark brown, and the apex black. Clypeus mainly reddish brown with dark clypeal marks compound of two large sub-rectangular areas, pale clypeal marks on the clypeus resumed to a yellow-orangish inverted T-shape that is a more extended on the area between the paraocular area and the labrum. Clypeus densely and entirely punctate with a coarse and deep punctation (interspaces of ≤ 1 / 2 the diameter of a puncture but generally smaller). Clypeal carina protruding, slightly blunt but not very blunt and impunctate (vertical bar of the yellow T). Clypeus entirely, evenly but sparsely covered by fulvous pubescence with the hairs slightly longer than the diameter of an ocellus. Paraocular areas protruding and yellow, mainly impunctate except at the base, near the insertions of the antennae (punctation similar to the clypeus). Protuberance of the apical margin of the clypeus of approximately the diameter of the eye (or slightly less). Scape anteriorly dark orange or slightly reddish, posteriorly dark brown to black and covered by fulvous to slightly orange pubescence that is longer than the width of the scape. A 2 dark brown to slightly reddish. Anterior surface of A 3 mainly orangish brown, basally with a paler orange area and apically with a narrow ivory-white line; posterior surface dark brown to black. A 4-5 basally dark brown and apically orange, ending in a narrow ivory-white line on the anterior surface, posterior surface dark brown to black. A 6-12 brown-orange on anterior surface and posterior surface dark brown to black. A 3-12 entirely covered by very small, hardly visible, white pilosity. A 2 anteriorly and apically with a small tuft of very small (but larger than the pilosity on the other articles) fulvous hairs. A 3 longer than wide, slightly longer than 4 + 5 + 6. A 4-7 shorter than wide. A 8-11 squared, as long as wide or very slightly shorter. A 12 not cylindrical, obliquely truncated at the apex. Frons to gena black (except a yellow triangle at the margin of the frons) and not evenly covered by fulvous pubescence of various length that is denser near the apical insertions. Presence of some long black hairs near the ocellus. Genae with very long white to slightly yellow hairs.

Mesosoma: Mesosoma entirely covered by bright fulvous-orange pubescence, without any black hairs intermixed in the pilosity of the dorsum. Scutum entirely, finely, and closely punctate with interspaces generally ≤ 1 / 2 the diameter of a puncture. Presence of a depression, the width less than the diameter of a surrounding puncture, on the centre of the scutum that does not go to the end of the scutum. Presence of two small but deep depression on the scutum, on each side, near the tegulae, symmetrical. Scutellum finely and densely punctate with interspaces of generally ≤ 1 / 2 the diameter of a puncture. Presence of a small sharp carina at the centre of the scutellum that does not go on all the length of the scutellum. Cuticle of the mesosoma deep black under the pilosity. Tegulae hyaline brown-fulvous, sparsely and shallowly punctate with interspaces of twice (sometimes more) the diameter of a puncture. Wings sparsely covered by dark hairs on the veins and inside the cells with a denser pilosity on the veins. Apex of the wings covered with very sparse and dark brown protuberances that are not similar to the hairs. Wings translucent but slightly yellow. All legs with an brownish orange cuticle, except for the hind tibiae that are exteriorly a bit darker and the basitarsi that are deep brown. All legs exteriorly covered by bright orange-fulvous pubescence and interiorly covered with a slightly darker pubescence. Tarsal claws of all the basitarsi bidentate with the second tooth situated on the middle of the main claw. Apex of mid tibia with one long and thick almost hyaline brown spine which is crenulate on one side and smooth on the other side; the spine is curved at the apex. Apex of hind tibia with two long and thick almost hyaline brown spines which are crenulate on one side and smooth on the other side; spines curved at the apex.

Metasoma: T 1 entirely and evenly covered by short fulvous pubescence except on the side where there are longer hairs of the same colour. T 2 almost entirely covered by short fulvous pubescence, except a little patch of short black hairs on the centre. Discs of T 3-4 at least partly covered by short black pubescence, the pale pubescence on the apical part forms hair bands that are wider at the centre of the terga. Some fulvous hairs are intermixed with the black hairs of T 3-4, the hairs become longer when going towards the sides of T 4. T 5 mainly black-haired with short black hairs, laterally with two fulvous hair tufts composed of sparse hairs. T 1-5 entirely, evenly, and sparsely punctate with shallow punctation and interspaces several times the diameter of one puncture. Integument of the terga mainly black but some parts of some apical margins are brown to ochraceous it is therefore highly probable that the apical margins were originally deep brown to ochraceous in fresh specimen (similarly to A. pendleburyi and A. feronia ) but the integument decoloured with the time. All sterna mainly glabrous, hairs limited to sparse band at the apex of some sterna (2, 4–6). Integument of all the sterna dark brown to orangish but not dark. S 1-3 with only a few sparse punctures on the discs, the apical margins and sometimes the sides more densely punctate but with interspaces of approximately the diameter of a puncture. S 4 more densely punctate at the apex and less densely at the base, interspaces become wider towards the base with only a few sparse punctures. S 5 densely punctate at the apex and on the sides but interspaces become wider towards the base with only a few sparse punctures. S 6-7 entirely, evenly, and densely punctate with interspaces of at most the diameter of a puncture (generally less).

Remarks.

This description is based on only one specimen, determinators should therefore consider that intraspecific variation could occur for this species, especially on some characteristics like the clypeal marks, the colourations, or even the morphology of the mandibles. The holotype seems to have lost pilosity on the mesosoma: the description about the pilosity of the mesosoma may therefore not be representative of the species. Consider the colour of the cuticle of the apical margin of the terga in fresh and collection specimens as decolouration can occur in collection specimens.

The male of this species is currently unknown but this species seems, based on our available specimen, to be distributed in South Borneo. However, as only one specimen is known, the distribution of this species on the island of Borneo cannot be known precisely. As A. celineae sp. nov. is morphologically close to A. pendleburyi , determinators should be careful regarding the identification of this group of closely related species in this region.

Amegilla celineae sp. nov. is currently considered as closely related to A. suzanneae sp. nov. and A. pendleburyi due to the morphological and biogeographical proximity (Fig. 26 ). New collection and genetic studies should be performed to better characterise the relationship between these three species and maybe also with A. feronia which is also morphologically closely related to A. pendleburyi . Moreover, new collections will permit to have a better understanding of A. celineae sp. nov., either biogeographically or ecologically as little is known due to a small number of specimens (only the holotype) currently available.

Etymology.

Based on the name of FC’s partner in life, Céline, who provides much support.

Distribution.

Amegilla celineae sp. nov. seems, based on our available specimen, distributed only on the island of Borneo: the collector of the holotype wrote “ S. Borneo ” on the label, but the name of the location provided leads to eastern Borneo, in the Indonesian part of the island. “ S. Borneo ” was therefore interpreted as being the Indonesian part of Borneo as a whole.

Figures

Figure 8. Holotype of A. celineae Carion, sp. nov. (RMNH). A. Labels of the specimen; B. Habitus in profile view; C. Face in frontal view; D. Labrum in ventral view; E. Protuberance of the clypeus in profile view; F. Terga in dorsal view.

Figure 26. Distribution map for four morphologically close species in the Indo-Australian Archipelago: A. celineae Carion, sp. nov. (blue points), A. feronia (Lieftinck, 1944) (red points), A. pendleburyi (Cockerell, 1929) (green points), and A. suzanneae Carion & Wood, sp. nov. (orange points). The empty points represent specimens collected before and in 1950 while the full points represent specimens collected in 1951 and after.