ENTOMOLOGIST'S MONTHLY MAGAZINE 47

TAXONOMY, DISTRIBUTION AND NESTING BIOLOGY OF

THE VESPA MANDARIIVIA GROUP (HYM., VESPINAE)

BY MICHAEL E. ARCHER

The hornets, Vespa mandarinla (Smith, I852a) and V. soror (duBuysson, 1905) are widespread on mainland south-eastern Asia andextend to the islands of Hainan, Taiwan and Japan. This paper reportsthe taxonomy, distribution and nesting biology of these two species.They can be readily separated from other Vespa species as follows:

l. Head strongly produced behind the eyes, i.e. in lateral view the genal width of thehe ad is greater than I .8 times the eye width in the female and 1 .4 times in the male; indorsal view the distance between the posterior ocelli is less than 0.16 the distancefrom thc posterior ocelli to the back of the head and 0.2 in the male.

2. The apex of the aedeagus is spade-shaped so that its basal margin is more or less atright angles to the shaft (fig. 1).

Fig. l. - Dorsal view of male genitalia of Vespa mandarinia.

These two character states are derived (Archer, 1994) so the V.mandarinia group is holophyletic (Mayr & Ashlock, I99l). The V.mandarinia group shares with the V. tropica group the derivedcharacter state shown by the female of the lateral apical margin of the

20th March ,1995 Vol. 131 (1995)

48 ENTOMOLOGIST'S MONTHLY MAGAZINE

clypeus produced as a blunt triangular projection (Archer, 1991b) sothat the V. mandarinia and V. tropica groups form a larger holo-phyletic group.

This paper attempts to reduce the number of colour subspecies bysynonymy. In addition informal names are proposed to replace thesubspecies names.

TAXONOMY AND DISTRIBUTION

V. mandarinia Smith, I852a was described from eastern China(Zhejiang) in terms of colour characteristics without reference tostructural characteristics. V. magnifica Smith,, I852b from northernIndia was also described only by colour characteristics. Smith con-trasted the eastern V. mandarinia with broad yellow apical gastralbands with the western V. magnil'ica with narrow yellow apical gastralbands. Bequaert (1936) recognised that I/. mandarinia and V. mag-nifica belonged to the same species with the new combination V.mandarinia magnifica.

V. bellona Smith , 7871was described from western China (Yunnan)(Moore er a\.,I877).Du Buysson (1905:525) synonymised V. bellonawith 7. magnifica. V. bellona is a light coloured variety of V. mag-nifica, and can be mainly recognised because large parts of the thoraxare coloured yellowish brown instead of black. Du Buysson (1905) alsodescribed the distinctive structural characteristics relating to thevertex and apical margins of the clypeus of V. magnifica.

V. soror du Buysson 1905 was described as a variety of V. ducalisSmith, 1852, despite the structural characteristics of the vertex andapical margin of the clypeus being similar to V. magnifica. Van derVecht (1957) recognised the confusion and proposed the new combina-tion 7. mandarinia soror. Archer (199la) showed that V. mandariniasoror was sympatric for part of its geographical distribution with V. m.mandarinia but still retained its distinctive colour characteristics soshould be given specific status, V. soror.

Cameron (1903) described V. mandarinia variety latilineata fromJapan. Van der Vecht (1959) used the combination V. mandarinialatilineata. Radoszkowski (1857) described V. japonica also fromJapan. Du Buysson (1905) recognised that V. japonica was a colourvariety of V. mandarinia. Thus the Japanese colour form of V.mandarinia should be named japonica (Matsuura & Yamane, 1990). V.mandarinia japonica probably has the pronotum less constantlymarked ferruginous and the posterior gastral bands wider than on V. m.mandarinia but in practice it is difficult to separate these two colourforms. It is proposed that japonica be made a new synonym ofmandarinia.

Sonan (1929) described V. magnifica variety nobilis from Taiwan.V. mandarinia and V. soror cannot be satisfactory separated by

ENTOMOLOGIST'S MONTHLY MAGAZINE 49

structural characteristics but are readily separated by colour character-istics:

l. Third to the sixth gastral terga in the female and to the seventh gastral terga in themalc black. at most with a narrow apical orange band on the third gastral tergum .......

- fr'i,.r ;;;h; iirir' g,,,i"i;;;; ;; i;; i;;;i; ""a

," ir'".i;it ##;'i:.:Jil'i# #il:with either a narrow or broad apical orange band. tergum six in the female and tergumseven in the male largely orange ..... mandarinia Smith, 18-52

TABLE 1. -THE COLOUR CHARACTERISTICS OF THE SUBSPECIES OFVESPA MANDARINIA.

Characteristic magnifica mandarinia nobilis

Colour band on thefirst and secondgastral tcrga.

Posterior lightcoloured band onthe third to fifthgastral terga.

Two bands: broadanterior darkcoloured band, verynarrow posteriorlight coloured band;sometimes lightcoloured patches onanterior part of firsttergum.

Very narrow, moreor less restricted torims of the terga.

Three bands:anterior andposterior lightcoloured bands withan intermediatedark coloured band;bands more or lessof same width.

Broad, extendingfor at least one thirdacross the terga.

Three bands:anterior lightcoloured band notvery distinct;intermediate darkcoloured band muchbroader thanposterior narrowlight coloured band.

Narrow, extendingless than one thirdacross the terga butnot restricted moreor less to rims of theterga.

TABLE 2. -THE SUBSPECIES AND INFORMAL COLOUR FORM NAMESFOR YESPA MANDARINIA.

Subspecies lnformal colour form name

mugnificu

mundurinia

nobilis

Western or north Indian to western Chinese.

Eastern or Chinese-Japanese.

Taiwanese.

V. mandarinia can be seen as consisting of three subspecies separ-ated by the colour characteristics given in Table 1. The three sub-species names may be replaced by the informal colour form names(Table 2). The geographical distribution of V. mandarinia is shown intig. 2A. the distribution of the three colour forms:

50 ENToMoLocIST's MoNTHLY MAGAZINE

Western or north Indian to west Chinese: Northern India (UttarPradesh, Assam), Nepal, Sikkim, Bhutan, Burma, Laos, Pen-insular Malaysia, western China (Yunnan, Sichuan).

Eastern or Chinese-Japanese: China (Sichuan, Hebi, Flunan,Jiangxi, Fujian, Zheiiang), Korea, Russia (Ussuriland), Japan(Hokkaido, Honshu, Kyushu).

Taiwanese: Taiwan.

The geographical distribution of V. soror (fig. 28) is Burma, north-ern ThailanO, Laos, North and South Vietnam and southern China(Hainan, Yunnan, Guangdong, Fujian).

Fig.2. - The world distribution of: A, Vespa mandarinia, B, Vespa soror.

ENTOMOLOGIST'S MONTHLY MAGAZINE

NESTING BIOLOGY

The nesting biology of V. mandarinia is well known from studies ofthe eastern colour form from southern Japan (Matsuura, 1966, 1969,l97la,197lb,1984, Matsuura & Sakagami,I9J3, Matsuura & Yamane,1990). Matsuura has provided further information to the author(personal communications 1979, 1980, 1983). Further information isgiven by Suzuki et al. (1961), Iwata (I97I) and Yamane & Makino(1977). Yamane (1977) gave some information on the Taiwan colourform of V. mandarinia. Yamane (1977) is written in Japanese and I amgrateful to S. Martin for partial translation of this paper. Little informa-tion seems to be available on the western colour form of V. mandarinia(Bingham, 1888) and none is available on V. soror. Thus the followinginformation refers to the eastern colour form of V. mandarinia unlessotherwise stated.

Queens over-winter in the ground or sometimes in straw heaps. Eachqueen excavates a cavity near the surface of the ground in moist soil.The entrance of the cavity is plugged and the queen passes the winterhanging from the top of the chamber.

The queens emerge during April and each founds its nest alone. Nestfoundation is from mid to late May, with the first workers emerging inlate June. Workers usually start foraging when two to three days old.As the workers start foraging the queen usually ceases the extranidalactivities of food and nest material collection in the space of a fewdays. Intranidal activities of the queen in feeding the larvae and nestbuilding gradually decrease with the emergence of the workers butusually cease after about 30 days.

Further workers are reared in the small cells but after late Augustlarge cells are built to rear the sexuals. Males begin to emerge as adultsfrom late August to September and new queens from October intoNovember with males leaving the colony from early October and newqueens from early November. Unusually for hornets, mating takesplace at the entrance of the nest where males attempt to mate with theemerging queens. Ono et al. (1985), Ono & Sasaki (1987) and Ono(1988) investigate the pheromones that control the aggregation of themales at the nest entrance and the attraction to each other of the malesand new queens.

The mother queens die from late September to early November andthe colonies cease activity during late November. There are about sixmonths of colonial activity and this may therefore be considered a longcycle.

The queens usually select underground cavities as nest sites. Thecavities are either associated with rotten tree roots or are made bysmall vertebrates such as moles and snakes. The cavities are in welldrained soil along a slope or under an overhanging cliff. The nests arefound at a depth of six to 60 cm and the entrance tunnel is two to 60 cmlong. A few nests are found above ground (e.g. nine nests from a

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52 ENToMoLocIST's MoNTHLY MAGAZINE

sample of 56) either in tree hollows or mud walls and within one or twometies above the surface of the ground. The nests are found on hill-sides, parks and forests but are rare in the lowlands and high moun-tains. The Taiwan colour form of V. mandarinia also nests under-ground but the western colour form has been found in tree hollows nearthe surface of the ground (Bingham, 1888).

The queen builds a comb of about 44 cells (range 3l-60) with a meancell building rate per day of 1.64 (range 0-4) and a mean egg laying rateper day of 1.53 (range 0-5). The envelope is bowl-shaped, not com-pletely enclosing the comb which is ventrally exposed within the nestcavity. The queen is able to excavate soil so as to enlarge the nest

cavity as the nest grows in size. The first workers emerge as adultsafter about 38 days from the queen nest.

In southern Japan, nests at maturity consist of four to seven combsalthough five to six combs are more usual. Mature nests contain about2700 cells with the largest nest having 4661 cells. The large cells are

clearly larger than the small cells although the size of the small cellsdoes increase during the development of the nest. The envelope is thinand absent at the bottom of the nest exposing the lower comb andproviding access to the combs. The workers continue to excavate soilto enlarge the nest cavity although stones too large to be carried dropto the bottom of the nest cavity. The ability of the queen and workersto excavate soil probably relates to the lack of relocation behaviour inthis species.

On Hokkaido, northern Japan, Yamane & Makino (1977) found thatnests were smaller than in southern Japan. The two nests in theirsample consisted of five combs, one with 681 and the other with 1149

cells. In the more southerly location of Taiwan Yamane (1977) foundnests to be larger with nine combs and about 6000 cells.

The top combs are used to rear workers and the bottom combs torear males and queens although the sexuals can be reared on any comb.The cells of the top comb can each be used to rear two or three wasps

while the cells of the lower combs rear one or two wasps.

During the period of rapid nest expansion, the worker developmentalperiod is about 40 days (range 34-45) (egg stage 6 days, larval stage 16,

iealed brood stage 18). At this time brood mortality is at about 5%. Thenumber of workers in a colony reaches a mean maximum of about 180

during September with a maximum of 514 recorded. Adult workers livefor about 15 days with a maximum length of life of about 35 days.

Male sealed brood appears from late August reaching a peak inOctober with a mean of about 150. Queen sealed brood reaches its peakof about 90 during November. Adult males in a colony peak duringNovember at about 75 with a maximum of 284. Queens also peakduring November at about 100 with a maximum of 396. It has beenestimated the mean colony rears about 272 males and 205 queens. Theworkers need to built about 800 cells before rearing queens. During

ENTOMOLOGIST'S MONTHLY MAGAZINE 53

queen rearing the larva/worker ratio is about two which represents justover 100 workers in the colony.

REFERENCES

Archer, M.E., l99la, The number of species that can be recognised within the genusVespu (Hym.. Vespinae). Entomologist's mon. Mog., 127 161-164; l99lb, Taxonomyand bionomics of the Vespa tropica group (Hym., Vespinae), ibid., 127:225-232; 1994,A phylogenetic study of the species of the genus Vespa (Hymenoptera: Vespinae). Ent.Scantl.,24:469-47t1. Bequaert, J., 1936, The common Oriental hornets, Vespa tropicaand Vespu ulfinis, and their colour forms, Treubia, 15:329-351. Bingham, C.T., 1888,Notes on some becs and wasps from Burma, J. Bombay nat. Hist. Soc., 3: 183-187.Buysson, R. du., 190-5. Monographie des gudpes ou Vespa., Annls Soc. ent. Fr.,73:485-63,1. Cameron, P., 1903, Descriptions of four species of Vespa from Japan, Ento-mologist,36:278-281. Iwata, K., 1971. Ethological notes on four species of Vespa, inAsahina, A., Gressitt, J.L., Hidaka, 2., Nishida, T. & Namura, K., EntomologicalErsa-r'.r Io commetnorate the retirement of Professor K. Yasumatsu: 279-223. Matsuura,M., 1966. Notes on the hibernating habits of the genus Vespa in Japan (Hymenoptera,Vespidac). Kontl'A, 34: 52-67; 1969, Behaviour of post-hibernating female hornets,Vespu, in the pre-nesting stage, with special reference to intra- and inter-specificdominance relationships, Jap. J. Ecol., 19: 196-203:-197la, Nesting sites of the JapaneseVespa species. Kontytt, 39: 43-541' 197lb, Nest foundation by the female wasps of thegenus Vespa (Hymenoptera, Vespidae), Kontyfi, 39: 99-105; 1984, Comparative biologyof the five Japanese species of the genus Vespa (Hymenoptera, Vespidae), Bull. Fac.Agric., Mie Univ., 69: 1-131. Matsuura, M.& Sakagami, S.F., 1973, A bionomic sketchof the giant hornet, Vespa mandarinia, a serious pest for Japanese apiculture, J. Fac.Sci. Hokkaido Univ. (6) Zool.,19:125-162. Matsuura, M. & Yamane, Sk., 1990, Biologyof the Vespine Wasps, Springer-Verlag, Berlin. Mayr, E. & Ashlock, P.D., 1991,Principles of Systematic Zoology, McGraw-Hill. Moor€, F., Walker, F. & Smith, F.,lli7l. Descriptions of some new insects collected by Dr Anderson during the expeditionto Yunnan. Proc. zool. Soc. Lond. 1871:248-250. Ono, M., 1988, Studies on the matingsystem in the giant horneI", Vespa mandarinia japonica Radoszkowski (Hymenoptera:Vespidae'). Bull. Fac. Agr. Tamagawa University, 28: 97-142. Ono, M., Sasaki, M. &Okada, I., l9fJ5, Mating behaviour of the giant hornet, Vespa mandarinia Smith and itspheromonal regulation. Proc. Int. Apic. Cong. Nagoya, Japan, 30:255-259. Ono, M. &Sasaki, M., 1987, Sex pheromones and their cross-activities in six Japanese sympatricspecies of the genus Vespa, Insectes soc.,34'.252-260. Radoszkowski, O.I., 1857,(pp. a0-a1) in Motschulsky, V. de, Etudes Entomologiques, 6, ll2pp., Helsingfors.Smith, F., 1852a, Descriptions of some new and apparently undescribed Species ofHymenopterousInsects from North China, collected by Robert Fortune, Esq., Trans. ent. Soc. Lond.2:33--15; ltt52b, Descriptions of some Hymenopterous Insects from Northern India, ibid.,2: .1-5-.1t3. Sonan, J., 1929. Research on Taiwan wasps, Trans. nat. Hist. Soc. Formosa,19: 136-149. Suzuki, S., Suzuki, H. & Tekeuchi, K., 1961, On the construction of the nestof a few kinds of hornets, Sci. rep. Yokosuka Cy. Mus., 6:83-92. Vecht, J. van der,1957. The Vespinae of the Indo-Malayan and Papuan areas (Hymenoptera, Vespidae),Zool. Verh. Leiden,34: 1-83; 1959, Notes on Oriental Vespidae, including some speciesfrom China and Japan (Hymenoptera, Vespidae), Zool. Meded., Leiden, 36:205-232.Yamane, Sk. & Makino, S., 1977, Bionomics of Vespa analis insularis and V.mantlurinia latilineata in Hokkaido, northern Japan, with notes on vespine embryo nests(Hymenoptera: Vespidae), Insecta matsum. (NS), 12: 1-23. Yamane, So., 1977, On thecollecting technique of vespine nests, based chiefly on practices through a survey inTaiwan from 1972 to 1974 (Hymenoptera, Vespidae). Seibutsu Kyozai (Kikani), 12:42-59.

The Univcrsity College of Ripon & York St John, Lord Mayor's Walk, York, YO3 7EX.Octohcr 7th. 1993.