Bumble Bees

Studies on Scandinavian Bumble Bees 137whitish-haired. Otherwise coat black. Interalarband parallel-sided.Variation. Yellow collar varying somewhat inwidth, yellow hairs of T' ranging from a slightadmixture in lateral patches to the entire tergite.White on Ta more or less pronounced, particularlydistal part of T5 with variable admixtureof black hairs. However, variations are minute,i.e. Scandinavian ?? and VV are colour-stable.MaleMorphological chcracters. Malar space nearlytwice the distal width and about the length ofAr* r* u. Longest hairs in pile of face usuallyshorter than antennal scape. Hind tibia withonly very few bristles, none of which exceedin general the decumbent hairs at the distalmargin; longest hairs in fringes of hind tibiabarely or not exceeding the greatest width ofthe segment (Fig. 38A). Hind basitarsus widerdistally than at the base. St, (Fig. 38ts). Apexof volsella (Fig. 38C) varying slightly in shape.Body of moderate to large size.Colour pattern Pile of vertex usually pronouncedyellow, anteriorly and laterally encroajhedby black hairs. Collar, usually extendingdown episternuffi, T', median anterior lunatepart of T, yellow-haired. Entire or the rnain partof Tu, St1-u and lateral patches of Sto-z whitishhaired;remainder of St u-, with black hairs.The colouring otherwise as in the female.Variation. Gena and venter of head with avariable admixture of whitish hairs, otherwisevariations as in the female.Distribution (Fig. 76)Scandinavia. Restricted to southernmost Sweden,which is the northern limit of the distributionof the species.Biotope: Apparently prefers rather arid areas.A total of about 135 specimens was examined.List of localities. Skdne: Alnarp, Bjiirred, Bjornstorp,Blentarp, Bulltofta, Bokeberg, Dalby, Eslov,Falsterbo, Glimslov, Hohog, Hiilsingborg NRS ZML,Hflslov, Klostersagen, Kniistorp Z}r dB., Krageholm,Kungshult, Kyrkheddinge, Kdvlinge TCL ZML,K6selberga,Lund GNM ZldB ZML, Loddekopinge, LoderupNRS ZML, Malmo, Nosaby, Nytorp" NiisumGNM, Ravlunda, Rea, Simrishamn NRS, Sjostorp,Skarhult, Sodra Sandby ZI|I{B ZML, Torekov, TrelleborgGNM ZML, Veberod, Vellinge, Villands Vflnga,Vinninge, Vitemolla, Ystad NRS, Ortofta, OstratorP,Oved NRS ZML, Ahus, Alabodarna. Blekinge; Hdllevik,Kristianopel GNM. Halland: Falkenberg, Flalmstad,6stra l(arup, Aku[a GNM.The total distribution of the subspecies, B. ruderatuseurynotus Vogt. Europe (cf. the worlddistribution of the species) with exception ofthe Iberian peninsula and the Mediteffaneanisles (Pittioni & Schmidt 1942).BiologyFlight seeson. From the middle of I\4ay tothe end of September. Queen: 12 May-26 Sept.;worker : 7-21 Aug.; male : 24 July-22 Sept.SUBGENUS THORACOBOMBUS DALLATORREThoracobombus Dalla Torre, 1880, p. 40, typespeciesBombus sylvarum (Linnaeus) by designationof Sandhouse (1943).( Chromobombus Dalla Torre, 1880, p. 40,type-species Bornbus muscorum (Linnaeus) bydesignation of Sandhouse (1943). AgrobornbusVogt, 1911 , p. 52, type-species Bornbus agrorltm(Fabricius), 1787 nec Schrank, 1781 by designationof Sandhouse (1943). RuderariobombusKrtiger, 1920, p. 350, type-species Bombus rude'rarius (Mtiller) by designation of Yarrow (1971).Adventoribombus Skorikov, 1922a, type-speciesBombus sylvarum (Linnaeus) "by designation ofYarrow (1971), who refutes the designation ofSandhouse (1943), viz. Agrobonfuts ( Adventori'bombus) adventor Skorikov, 1922 ( - Agrobom'bws adventor Skorikov, l9l4a), as being invalid.)Queen, workerHead longer than wide. Clypeus, malar spacehardly to markedly longer than respective distalwidth, yet less than l1/z times this width (occasio-