ENTOMOLOGIST'S MONTHLY MAGAZINE 45 TAXONOMY, DISTRIBUTIONAND NESTING BIOLOGY OF wspA ORTENTALIS L. (HyM., VESPIDAE) BY MICHAEL E. ARCHER Vespa orientalis L., l77L is a common and widespread species of hornet found throughout south-eastern Europe, north Africa and southwestern Asia. In a cladistic study of Vespa, Archer (1994) found that this species was an isolated species with no clear phylogenetic relationship with any other Vespa species. About 550 specimens have been examined in this review of the colour forms. TAXONOMY AND DISTRIBUTION of. V orientalis jurinei de Saussure, 1"853; aegyptica Andr6, 1884; Including the nominate colour form, six colour forms have been described: zavattarii Guiglia & Capra, L933; somalica Giordahi-Soika, 1934 and arabica Giordani-Soika, L957. Guiglia (1972) and Richards (1984) each considered five of the colour forms. The female and male do not seem to show any autapomorphies or combination of morphological characters by which they can be readily recognised. Fortunately, except for a colour form found in Albania, the species can be readily recognised by the following combination of colour characteristics: second, flfth and sixth gastral terga entirely reddish or dark brown; third, and usually the fourth, gastral terga mainly yellow with a complete yellow band. The Albanian colour form has all the gastral terga coloured brown except for two yellow marks on the apical margin of the first gastral tergum. These latter marks will distinguish the Albanian colour form from other species of Vespa where the gaster is entirely or almost entirely dark brown or black (V ffinis L., 1764; V basalis Smith, 1852;V dybowskii Andr6, L884; V. fervida Smith, 1858; V mocsaryana du Buysson, 1905; V tropica (L., 1758)). The Albanian colour form, V jurinei de Saussure (1853) was shown to be a colour variety of V orientalis by Andr6 (1884). This opinion was supported by Guiglia (L972). Since this variety falls within the range of the nominate subspecies I proposed it should be treated as part of the nominate subspecies. The Egyptian colour form, V orientalrs variety aegyptica Andr6, 1884, is characterized by an enlargement of the two small yellow marks on the apical margin of the first gastral tergum which extends towards the lateral margins of, and up to one third across, the tergum. The fourth gastral tergum is entirely dark reddish-brown except for a lateral yellow spot. Typically-coloured forms and forms intermediate in colour between the typical and variety aegyptica are also found in Egypt. This range of colour variation in Egypt was noted by Guiglia (1972) and Richards (1,984). Since the variety aegyptica is found within the range of the nominate Z7thMarch,1998 Vol. 134 (1998) 46 ENTOMOLOGIST'S MONTHLY MAGAZINE subspecies I agree with Richards (L984) that the variety should be treated as part of the nominate subspecies. V orientalis zavattarif Guiglia & Capra,1993, from the central Sahara, is particularly characterized as follows: the reddish-brown colours are on the gaster, and the yellow marks on the apical darker particularly -of the first gastral tergum are enlarged extending to the lateral margin margins of, and up to one-third across, the tergum. ! havg found indiiiduals indistinguishable from V orientalis zavattarii from Iran and India (Andhra Pradesh, Haryana and Bihar). Individuals intermediate in and V orientalis zavattarii have been found colour between the typical from Libya, Israel, Oman, Bahrein, Turkmenistan, Tadzhikstan and Pakistan. Since V orientalis zavattarii is found in several geographical areas and intermediate coloured forms between it and the typical are widespread, I propose it should be treated as part of the nominate subspecies (syn. n.). V orientalis somalica Giordani-Soika, 1934 and V orientqlis arabica Giordani-Soika, 1957 are both found in southern Arabia. Richards (1984) found that there were no marked differences between the two subspecies and proposed that V orientulis arqbica be treated as a new synonym of V orientalis somalica.I agree with this proposal. U orientalis somalica is particularly characterized by very dark reddish-brown gastral coloration (appearing almost black at first sight), the absence of, 6r the presence of very narro% yellow marks at the apical margin of the first gastral tergum, and dark blackish brown wings. I have not Tound individuils of V orientalis somalica outside southern Arabia and Somalia. Individuals lacking the yellow marks at the apical margin of the first gastral tergum have been found in the surrounding countries of Iran, Ira{ Turkey and the island of Crete and are considered as part of the nominate subspecies. The distribution of the two subspecies of V orientalis (fig. 1) are as follows: V orientalis orientalis-southern Italy including Sicily, Malta, Albania, Greece including Crete, Bulgaria, Cyprus, Turkey, Syria, Israel, Jordan, Iraq, Bahrein, United Arab- Emirates, northern Oman, Turk' menisian, iadzhikstan, Iran, Afganistan, Pakistan, Kashmir, India (Punjab, Haryana, Uttar Pradesh, Bihar, Wet_t Bengal, Maharashtra, Andhra Pradesh), Nepal, Algeria, Libya, Chad, Egyp, and Sudan' U orientalis somalicaAaudi Arabia, South Yemen, Yemen, south Oman and Somalia. I have seen a specimen from China (Fujian) which presumably-had been transported there by accide11. Requaert_(19L8) gave a.record from Madagascir where it wai also probably introduced accidentally. NESTING BIOLOGY The nesting biology of V orientalis has been studied in-Egypt (Mellor' lg27,wafa, iglo,witu et al.,l-968, Wafa & Sharkawi,_l9i:12), and Israel (Darchen , Ig64,Iihay, 1965, 1976,1982 (pers. comm.), Ishay et a1.,1967, ENTOMOLOGIST'S MONTHLY MAGAZINE Fig. 1 - 47 Distribution map of Vespa orientalis. Ishay et al., lg7z,Ishay et al.,1983, Ishay & Lior, 1990). Mellor (1927) summarized information from Sicilian sources. The personal communication from Ishay, 1982, consisted of the numerical characteristics of 76 colonies collected from 13 July until 1 November. These data did not contain separate counts of small and large cells or meconial counts. Nesting sites Nesiing sites are underground or aerial, usually in an enclosed space. In Egypt neJting nests are usually underground or in a_space in a.rock or *iif. Aerial sltes were 3V270 cm above the ground. Other Egyptian sites included inside empty bee hives, a corner of a disused outhouse at ceiling level, and under the eaves of a porch. In Israel nesting sites are frequently associated with rural and urban settlements usually underground or in walls. From a sample of-39 sites, L9 were undergrounO, fS in *alls, two in roof spaces, two under floor boards and one in i cardboard box. The underground sites were usually started in the burrow of a mol e nt or other small rodent. From a sample of' 76 underground sites the mean depth of the nest was 36 cm with90Vo of the sites being between 20 and 56 cm. In Sicil-y two underground sites were situated at depths of.24 cm and 40 cm. 48 ENToMoLocIST's MoNTHLy MAGAZINE C olonial lifu history characteristics In Egypt and Israel, queens can emerge from over-wintering sites from mid-February during periods of warm weather. The main over-wintering emergence is from mid- to late April. The queen then initiates a nest from mid- to the end ofApril. The first workers emerge from mid-May until the end of May and continue the building of the small cells. The building of the large cells to rear the sexual brood starts from early September with the sexuals emerging from mid-October. Some males are reared in small cells. In Israel, by the end of August 4V5OVo of colonies have lost their queens and the workers of the resulting orphaned colonies lay male eggs which emerge as adults during November. Brood rearing becomes much reduced during November and the colony usually ceases to function by the of November. The old queen usually dies during November. Sometimes a few workers and males may persist into December. Mating flights take place during October into November with the fertilized queens entering over-wintering sites by the end of November. The life cycle lasts for about seven months (205 days) from mid-May until mid-November. end Queen colony and queen usurpation In Israel, the queen builds a single comb of about 2F30 cells. In laboratory nests the queen may only build a comb of I2-L6 cells. In one laboratory colony the queen took about 35 days to rear the first workers (egg stage 54 days, larval stage 15-16 days, sealed brood stage 15 days). In a second colony the queen took 4145 days (egg stage 5-6 days, larval stage 2L-24 days, sealed brood stage L5-1,6 days). In both of these laboratory colonies the queen killed larvae to use as food to feed the other larvae. One, two, or more dead queens were often found at or near the nest of field colonies. These dead bodies are an indication of intraspecific queen usurpation. In a laboratory situation it was possible to get an alien queen to attack a queen with a comb containing egg and larval cells. In the fight usually the alien queen was killed or chased from the colony. Sometimes both queens would be killed and the colony orphaned. An orphaned colony would then be adopted by another alien queen. ln a colony with its first few workers, the alien queen would be attacked by the workers rather than the queen and usually killed or chased from the colony. Queen usurpation was possible when only a few workers were entrance present. Nest development In the following account all numerical data refers to colonies collected in Israel (Ishay, L982, pers. comm.) unless otherwise noted. During May the number of cells in a nest remained low, at less than L00 cells. The number of cells slowly increased during June and the first half of July to about 250 cells (range 32-543 cells). From mid-July, the number of cells rapidly increased so that by the July-August transition about 730 cells ENTOMOLOGIST'S MONTHLY MAGAZINE 49 (108-1497), and at the August-September transition about L400 cells (243-3386) were present. By early October about 2OOO cells (5994202 cells) were present when cell building more-or-less ceased. From the above cell data it is possible to estimate weekly and daily cell building rates. During June the cell building rate was about 33 cells per week (4.7 cells per day). During the mid-July interval the rate was increased to about 200 cells per week (29 cells per day). The building rate then decreased during August to about 155 cells per week (22 cells per day) before increasing again in early September, when large cell building took place, to about 290 cells per week (4L cells per day). Later the cell building rate rapidly decreased, often abruptly with the appearance of heavy rains. In Israel the mature colony usually consists of.34 combs (range L-6 combs), in Egypt +IO combs and in India (Akre, 1982) five or more combs. In the mature colony the upper or older combs consist of small cells (side-to-side diameter about 7 mm, depth L6-18 mm) while the younger lower combs consist of large cells (side-to-side diameter about 9 mm, depth 22-24 mm). One mature colony where the large and small cells were counted separately, consisted of 1,422 small (77Vo) and 425 (23Vo) large cells. Small cell building more-or-less ceased by mid-September. The number of large cells remained very low during the first half of September, after which the number started to increase rapidly until mid-October when large cell building more-or-less ceased. The cell walls consist of layers of mineral particles between layers of chewed wood fibres held together with saliva secreted by the workers. In one sample the organic content of the cell walls was 9.5-29.5Vo and in a second sample IL.241.3Vo. The mineral particles were predominantly quartz or sand granules. The silk secreted by the larvae before pupating helps to reinforce the cell walls. The pillars separating the combs consist only of chewed wood fibres mixed with saliva. In underground nests no envelope is built to surround the combs. In aerial nests, or where combs are exposed, an envelope is built. The envelope consists of grey chewed wood fibres streaked with the dark brown, black, and red earth particles. The wood fibres and earth particles are held together with worker saliva. The immature brood The number of immature brood closely followed the number of cells until the end of August, except for the 5-?0Vo of the cells which may be empty of brood. From the beginning of September the number of empty cells increased to about 6OVo by the end of October. The increase of empty cells coincided with the building of the large cells. The rearing of lhe sexual brood led to the gradual abandonment of the upper combs of small cells. 50 ENToMoLocIST's MoNTHLY MAGAzINE The mean number of egg cells at the July-August transition was about 160 (2I-358), increasing io about 20O (33-372)_at-the August-S_eptember transition, una probablyleaching a maximum of about 300 (1^51+15) Uy mid-september, after which ther-e was a decrease by the end of October to about 80 (5-262) tgg cells. The mean num6er of larval cells at the July-August transition was about 250 (32486), increasing to about 49O (99-1168) at !he. Augglt_September iransition, and probably reagh|ng a maximum of about 580 by mid-Septembbr, after which there was a decrease by the end of October to about 350 (38-7L7L) larval cells. The mean number of sealed brood cells at the July-August transition was aboutzl} (2H8I), increasing to about4TO (56-1280) at-theAug"lt: September transition, and probably reaching a maximum of about 600 the end lZiO-tOZ) by mid-septemb-er, after which there was a decrease by of October to about 220 (9G338) sealed brood cells. The small cells, which are used to rear the workers and males, each may be used to rear up to three adults. The large cells, which are used to reai the queens and sometimes males, are never used more than once. It has been estimated that in Israel a queen could lay more than 4000 eggs during the development of a colony. -In Egypt the mean developmental period of the worker brood during July and August was 29 (eggstage 5,larval stage 9.5, sealed brood stage 1,4:, days. During September, October and November the worker brood was-negiected so thal the developmental period became more variable. The mein developmental period of the queen brood during September and October was 42 (-egg stage 5, larval stage 1"5, sealed brood stage ?2) d7ys, Males reared in the large cells had a mean developmental period of 40 (egg stage 5, larval stage L5, sealed brood stage 20) days. The-developmental plriod of males raised in the small cells was rather variable. 1it-StS) Adults During June the mean number of workers in a colony was very mean number of workers started to increase (3-73) during mid-July, 95 (MI2) at the about 30 during July reaching July-August transitio n, 250 (32:791) at the August-September transition, with a peak of about 43O (14T912) from mid-september until midOctober, after which the number of workers decreased. Knowing the approximate cell building rates and the number of workers ini colony, an estimate can be made of the number of cells built low-up-to about ten. The per day per worker. During June and early July the rate was about 0.9 cell during irer day per worker decreasing to about 0.12 cell per day per worker August and the first half of September. A maximum number of 260 queens and 263 males were found in a colony. The total production of workers, new queens and males from a colony has not been determined. ENTOMOLOGIST'S MONTHLY MAGAZINE 51' (12-64) In field colonies the mean length of life of workers was 36'I vespiary a in days days. The mean il"grh of life wis increased to 45.5 *1i"i" f tobably the Ioragers -were protected .fto- predators' th:y reached Workers startJ forugTng from the age of three- days andi{ the colony' in remained and forage to ceased itre| the ale of 35-38 Oays '*orkers had a bimodal distribution' Workers of mortality the As such 7'L days) i.1i"g t" ieach ;;;d" iived.for-a mean 23.8 days (n-= 68, s'd' 54.8 days mean a for lived colony the in but the old workerr ttiut remained (n - 45, s.d. 6.4 daYs). REFERENCES insects' 4.: L-105' Akre, R.D., 1982, Social tS,lasPs:-in Hermann, H'R' (ed')' Socrcl the species of the press, N"* [i[. A*n"i Vf.n., 1994, A phylogenetic stldy oi Academic senus Vespa (Hym;6G;; il;pili"l, intomologica iand.,24: 469478. Andr€' E., 2, Vespinae, Beaune.Bequaert, J', 1g84, Species des Hyminoptires d'Eyro-pe et d'AlgZ1ie, based on the collection of the Belgiari ttre of V"rpidae ift" of 1"918, A revision Diplopterous wasps, 'Bul/' of Eihiopian a"list with E'xpedition, American Museum dngo orientalis' 7.es Am Mus. nat. nxt.,-ifi-Fs-:S+. Darchen, R., 1964, 9r^oi9ei9 de Vespa IY".:Yt soc', !t:141-1s8' cuigia' D" 1972' Les Guapes 9lg:l ;;;i;;t !1"o"s acu"iopryFeltr d'Europg occidentale.et Septentiqyb Masson' Paris' im Nest vonVespabrientalb, F', Dt' ent' Z',12: unO'ef.tiuitai Isha* J., 1965, Belnv',24: 397419;L976, Comb building by the oriental hornet (Ytt" oriennlis),Ay : of l43.Ishay, J., Biiin;H-S;fi, iI. &_!hulov, A.,.126'T,iontributions to the bionomics I)otan' J'S" en!',2:-45-lO6' !sha5 IiraetJ' Fab.), (U*W orientalis hornet the oriental Sociales Uy*"ropiiiiiiitii,,it") gnt*rclfuni Z.A. &pinchasovri., iggl, Combativeness among otl"ry"! hornet quee1L{nsgctes soc', A',lg72,.Cybemetic 3o: 5i49.Ishay, ilbitt"u S., Schaudinischky, L. & Scnwanlz, tarvag of ihe_oriental hornet, Vespa orientalis, 6th the adults'ani ;;;;^t-i;;;'i" Levano-n' D'r,{vi$or' N' & Internationat Congres" on-CyU"-"tics: 1133-f145.Ishay, J.S.r -d"n""ni"r, in the O.S., igS3,irtoiop"tlodicity stimulates cell size and caste determination & Lior' Ishay, J'S' 332-346' 3O: soc., Insectel \7i1, L' oriental hornet Vespa orientaiis Hymenoptera' S.8., iq90, Digging activity by the oriental hornet (V"tpo orientalis; 1927, Some Mellor, J'E'M', V*liir*l is co.iJutlo with solariadiation,,L Ethol-,8:61-68Fab., Bull. src. enl observations on the habits of the oriental hornet, vespa or.i.entalis, Fam' igyjr', ii: 80--95. ni"nroat, O.W., 1984, Insects of Saudi Arabia, Hymenoptera: Wafa, Vffiia"; (Social W;tJ tne eruUiun Peninsula),. Fauna SaudiArabia,6:423-440' Vespa orientalis' activity o-f the-oriental hornet 1-35. Wafa, A.K., El-torolossv, F'M' & Sharkawi' Erypt, 52: *27 ' s.G., 1968, StuOies on vespa orientalis F. (Hym., Vespidae),.8ul/. soc. ent. orientalis Fab" of Vespa biotogy to the ContriUution DlZ, Wafa, A.IC & Sn"rX"*ir'd .C., ibid., 56:219-226. A.K., 'nii. 1,956, Ecological investigations on the e"r. Agric. d;i;; i"i","103, University College of Ripon and York St John, York, YO3 7EX' January 5th, 1996. THE FOOD INSECTS NEWSLETTER The recent issue (Vol. t9' \9. 1., March tggl, tZ pp.) contains the first of a four-part series on Insects as human food in -the Great in the.state of r,oi,rri an'eihnologi"J ufpiou"h (Carin A. Miller), Insects a.s fglk medicines Alogo^, Brazil1i.C.W.'il,Iurquei & E.M. Costa-Neto) and short notes on recent events, medii coverage. For information, subscrip{on rates, etc' contact the Editor - Dr Florence V. Dunkel, Associate Professor, Dept' of Entomology,-Montana Fax (406) Stut" Uniu" rsity,324 lron Johnson Hall, Bozeman, MT 5971,7 - 0302m U'S'A' puUiistreO literature and 994-6029; e-mail : ueyfd@montana.edu