寄(ji)生(sheng)蜂(feng)(feng)(Parasitoid wasp),指(zhi)膜翅目細腰亞目中金小蜂(feng)(feng)科、姬蜂(feng)(feng)科、小蜂(feng)(feng)科等(deng)靠寄(ji)生(sheng)生(sheng)活的(de)(de)(de)多種昆蟲(chong)。它們的(de)(de)(de)寄(ji)生(sheng)方式(shi)很(hen)多,被寄(ji)生(sheng)對象從(cong)卵到(dao)成蟲(chong)的(de)(de)(de)各(ge)個階(jie)段,都可能被寄(ji)生(sheng)。所謂(wei)寄(ji)生(sheng)蜂(feng)(feng),就是從(cong)植食性蜂(feng)(feng)類(lei)進化到(dao)筑(zhu)巢性期(qi)間的(de)(de)(de)一群肉食性蜂(feng)(feng)類(lei)。與寄(ji)生(sheng)蟲(chong)一樣。
分成外寄(ji)生和內(nei)(nei)寄(ji)生兩大類。前(qian)者是指把卵(luan)產(chan)在寄(ji)主(zhu)體(ti)(ti)表(biao),讓(rang)孵(fu)化(hua)(hua)(hua)的(de)幼(you)蟲(chong)從體(ti)(ti)表(biao)取食寄(ji)主(zhu)身體(ti)(ti);后者是把卵(luan)產(chan)在寄(ji)主(zhu)體(ti)(ti)內(nei)(nei),讓(rang)孵(fu)化(hua)(hua)(hua)的(de)幼(you)蟲(chong)取食害蟲(chong)體(ti)(ti)內(nei)(nei)的(de)組織。內(nei)(nei)寄(ji)生形(xing)式者,被認(ren)為(wei)較為(wei)進化(hua)(hua)(hua)。
外(wai)寄(ji)(ji)(ji)(ji)生(sheng)者在(zai)產(chan)(chan)卵(luan)(luan)(luan)(luan)前(qian),必(bi)須(xu)克服一件事,就(jiu)是(shi)得讓寄(ji)(ji)(ji)(ji)主(zhu)(zhu)(zhu)無法動(dong)彈(dan),否則卵(luan)(luan)(luan)(luan)會(hui)(hui)被寄(ji)(ji)(ji)(ji)主(zhu)(zhu)(zhu)壓(ya)壞,甚至被寄(ji)(ji)(ji)(ji)主(zhu)(zhu)(zhu)咬死。因此,外(wai)寄(ji)(ji)(ji)(ji)生(sheng)蜂會(hui)(hui)先用產(chan)(chan)卵(luan)(luan)(luan)(luan)管(guan)蜇刺寄(ji)(ji)(ji)(ji)主(zhu)(zhu)(zhu),注射有(you)毒物質麻痹寄(ji)(ji)(ji)(ji)主(zhu)(zhu)(zhu)。也(ye)就(jiu)是(shi)說,產(chan)(chan)卵(luan)(luan)(luan)(luan)管(guan)除(chu)了產(chan)(chan)卵(luan)(luan)(luan)(luan)功能(neng)外(wai),兼具注入麻醉液的(de)(de)功能(neng)。此外(wai),還有(you)一個待(dai)解決(jue)的(de)(de)問題,就(jiu)是(shi)寄(ji)(ji)(ji)(ji)主(zhu)(zhu)(zhu)必(bi)須(xu)有(you)造繭性等隱蔽身體(ti)的(de)(de)習性,因為(wei)寄(ji)(ji)(ji)(ji)主(zhu)(zhu)(zhu)若(ruo)遭麻醉,行動(dong)變(bian)得遲鈍,容易受到敵害攻擊或(huo)其他外(wai)在(zai)環境的(de)(de)傷害,如果(guo)沒(mei)有(you)隱蔽自己的(de)(de)絕活,體(ti)表的(de)(de)寄(ji)(ji)(ji)(ji)生(sheng)蜂幼(you)蟲(chong)也(ye)將會(hui)(hui)與它同歸于盡。而采用內(nei)寄(ji)(ji)(ji)(ji)生(sheng)方(fang)式的(de)(de)寄(ji)(ji)(ji)(ji)生(sheng)蜂,問題就(jiu)沒(mei)有(you)那(nei)么嚴重。
此外,也有(you)像蜘(zhi)(zhi)蛛姬蜂這類具有(you)產卵特(te)技寄生蜂,它們(men)以蜘(zhi)(zhi)蛛網上的(de)(de)蜘(zhi)(zhi)蛛為寄主。當它突襲(xi)蜘(zhi)(zhi)蛛時(shi),會先刺蜇蜘(zhi)(zhi)蛛腳(jiao)的(de)(de)基(ji)部(bu),利用其暫時(shi)失(shi)去感覺之(zhi)際,在它的(de)(de)頭(tou)胸(xiong)部(bu)或(huo)腹部(bu)腹面產下一粒(li)卵,蜘(zhi)(zhi)蛛后來雖然恢復知覺,但(dan)由(you)于腳(jiao)摳不(bu)到卵,只好(hao)任由(you)孵化(hua)的(de)(de)姬蜂幼蟲(chong)吸血,而終(zhong)至死亡(wang)。
寄(ji)生蜂(feng)的(de)種類很多,分別寄(ji)生于(yu)寄(ji)主(zhu)的(de)不同(tong)發育階段,常見的(de)有小蜂(feng)、姬蜂(feng)、繭蜂(feng)、赤眼蜂(feng)、嚙(nie)小蜂(feng)等。
姬(ji)(ji)蜂(feng)(feng)(feng)(feng)(feng)是(shi)膜(mo)(mo)翅(chi)(chi)目(mu)姬(ji)(ji)蜂(feng)(feng)(feng)(feng)(feng)科的(de)一(yi)種寄(ji)生(sheng)(sheng)蜂(feng)(feng)(feng)(feng)(feng),膜(mo)(mo)翅(chi)(chi)目(mu)(Hymenoptera)姬(ji)(ji)蜂(feng)(feng)(feng)(feng)(feng)科(Ichneunmonidae,有(you)(you)重要經(jing)濟意義(yi)的(de)一(yi)個(ge)大科)昆蟲(chong)(chong)(chong)(chong)(chong)(chong)。分(fen)(fen)布很廣,約40,000種。形狀(zhuang)、顏色、大小(xiao)各(ge)異,一(yi)般(ban)(ban)1.2公分(fen)(fen)(約0.5寸)長(chang)。北美洲最長(chang)的(de)長(chang)針姬(ji)(ji)蜂(feng)(feng)(feng)(feng)(feng)屬(shu)達5公分(fen)(fen)。許多(duo)(duo)種的(de)腹部(bu)細長(chang)而(er)彎曲,像黃蜂(feng)(feng)(feng)(feng)(feng),區別一(yi)般(ban)(ban)在(zai)于觸角較長(chang),節較多(duo)(duo)。產卵(luan)(luan)器通常比身體(ti)(ti)長(chang)。許多(duo)(duo)種的(de)前翅(chi)(chi)有(you)(you)一(yi)黑點(dian)。寄(ji)生(sheng)(sheng)在(zai)蜘(zhi)蛛以(yi)(yi)及(ji)多(duo)(duo)類昆蟲(chong)(chong)(chong)(chong)(chong)(chong)上(shang)(shang),尤其是(shi)鱗翅(chi)(chi)目(mu)和其他(ta)膜(mo)(mo)翅(chi)(chi)目(mu)昆蟲(chong)(chong)(chong)(chong)(chong)(chong)。由于寄(ji)生(sheng)(sheng)在(zai)許多(duo)(duo)害(hai)蟲(chong)(chong)(chong)(chong)(chong)(chong)上(shang)(shang),總的(de)來說是(shi)益(yi)蟲(chong)(chong)(chong)(chong)(chong)(chong)。雌蜂(feng)(feng)(feng)(feng)(feng)在(zai)宿(su)(su)主的(de)幼(you)蟲(chong)(chong)(chong)(chong)(chong)(chong)或(huo)蛹(很少(shao)在(zai)卵(luan)(luan)或(huo)成體(ti)(ti))上(shang)(shang)產卵(luan)(luan)。幼(you)蟲(chong)(chong)(chong)(chong)(chong)(chong)取食(shi)宿(su)(su)主的(de)脂肪(fang)和體(ti)(ti)液,長(chang)成后(hou)織(zhi)一(yi)繭(jian)。如(ru)果宿(su)(su)主生(sheng)(sheng)活場所不(bu)是(shi)隱(yin)蔽的(de),則(ze)(ze)通常寄(ji)生(sheng)(sheng)在(zai)宿(su)(su)主體(ti)(ti)內(nei);若宿(su)(su)主生(sheng)(sheng)活在(zai)隱(yin)蔽處(chu)(如(ru)樹木(mu)孔(kong)道內(nei)),則(ze)(ze)常寄(ji)生(sheng)(sheng)在(zai)宿(su)(su)主體(ti)(ti)姬(ji)(ji)蜂(feng)(feng)(feng)(feng)(feng)外。一(yi)個(ge)宿(su)(su)主上(shang)(shang)多(duo)(duo)數只有(you)(you)一(yi)個(ge)幼(you)蟲(chong)(chong)(chong)(chong)(chong)(chong),但有(you)(you)時也(ye)可(ke)(ke)有(you)(you)多(duo)(duo)個(ge)幼(you)蟲(chong)(chong)(chong)(chong)(chong)(chong)寄(ji)生(sheng)(sheng)。赤(chi)眼(yan)(yan)蜂(feng)(feng)(feng)(feng)(feng)以(yi)(yi)眼(yan)(yan)紅色而(er)得名,它經(jing)常把卵(luan)(luan)產在(zai)松(song)毛蟲(chong)(chong)(chong)(chong)(chong)(chong)、玉(yu)米(mi)(mi)螟、二化螟及(ji)甘蔗螟的(de)卵(luan)(luan)中(zhong),幼(you)蟲(chong)(chong)(chong)(chong)(chong)(chong)就以(yi)(yi)寄(ji)生(sheng)(sheng)卵(luan)(luan)中(zhong)的(de)營養物質為食(shi),所以(yi)(yi)可(ke)(ke)以(yi)(yi)大量消(xiao)滅農林(lin)害(hai)蟲(chong)(chong)(chong)(chong)(chong)(chong);雌馬尼蜂(feng)(feng)(feng)(feng)(feng)可(ke)(ke)以(yi)(yi)把卵(luan)(luan)產在(zai)鉆入樹皮的(de)天牛(niu)幼(you)蟲(chong)(chong)(chong)(chong)(chong)(chong)體(ti)(ti)內(nei),以(yi)(yi)后(hou)它的(de)幼(you)蟲(chong)(chong)(chong)(chong)(chong)(chong)便(bian)(bian)以(yi)(yi)天牛(niu)幼(you)蟲(chong)(chong)(chong)(chong)(chong)(chong)為食(shi),直至吃(chi)得只剩一(yi)層皮。當它發現鱗翅(chi)(chi)目(mu)幼(you)蟲(chong)(chong)(chong)(chong)(chong)(chong)后(hou)便(bian)(bian)落到它的(de)頭部(bu),用(yong)長(chang)針狀(zhuang)的(de)產卵(luan)(luan)器刺入其腦部(bu),實施(shi)麻碎(sui)后(hou)被寄(ji)生(sheng)(sheng)幼(you)蟲(chong)(chong)(chong)(chong)(chong)(chong)便(bian)(bian)昏迷不(bu)醒(xing),然后(hou)被“劫(jie)”入穴中(zhong),產卵(luan)(luan)其中(zhong);其他(ta)如(ru)金(jin)小(xiao)蜂(feng)(feng)(feng)(feng)(feng)、姬(ji)(ji)蜂(feng)(feng)(feng)(feng)(feng)、小(xiao)繭(jian)蜂(feng)(feng)(feng)(feng)(feng)等是(shi)消(xiao)滅害(hai)蟲(chong)(chong)(chong)(chong)(chong)(chong)的(de)能手。左(zuo)圖是(shi)用(yong)赤(chi)眼(yan)(yan)蜂(feng)(feng)(feng)(feng)(feng)防(fang)治玉(yu)米(mi)(mi)螟,掛在(zai)玉(yu)米(mi)(mi)葉子上(shang)(shang)是(shi)赤(chi)眼(yan)(yan)蜂(feng)(feng)(feng)(feng)(feng)的(de)卵(luan)(luan)塊,每個(ge)小(xiao)白球里有(you)(you)40多(duo)(duo)個(ge)赤(chi)眼(yan)(yan)蜂(feng)(feng)(feng)(feng)(feng)卵(luan)(luan)。
黑(hei)青小蜂(feng)(Dibrachys xavus)棉(mian)(mian)紅(hong)鈴(ling)蟲(chong)等的(de)天敵,金(jin)小蜂(feng)科。雌成蟲(chong)體長約(yue)2.8毫米,黑(hei)色(se),翅透(tou)明有金(jin)屬(shu)光澤,腹(fu)部紡(fang)錘形。雄成蟲(chong)體長約(yue)2毫米,腹(fu)部第一、二(er)節(jie)間(jian)有半透(tou)明的(de)黃白色(se)帶。年(nian)生(sheng)(sheng)11-12代。在越冬結繭的(de)棉(mian)(mian)紅(hong)鈴(ling)蟲(chong)幼蟲(chong)體上寄生(sheng)(sheng),使其(qi)死亡。用于防治(zhi)棉(mian)(mian)花(hua)倉庫內的(de)棉(mian)(mian)紅(hong)鈴(ling)蟲(chong),倉庫內放蜂(feng)后,寄生(sheng)(sheng)率(lv)很高。
與捕食(shi)性昆蟲(chong)不同的是(shi),寄(ji)生(sheng)性昆蟲(chong)一(yi)般都是(shi)成蟲(chong)積極(ji)地尋找寄(ji)主,當(dang)發現寄(ji)主后(hou),將卵產于體(ti)內。幼蟲(chong)孵(fu)化(hua)后(hou)取食(shi)寄(ji)主的營養,和(he)寄(ji)主共(gong)生(sheng)一(yi)段時間后(hou)才(cai)使(shi)寄(ji)主死亡。幼蟲(chong)不能主動尋找食(shi)物。
寄生蜂產的幼卵安靜地躺在夢幻般的薄紗結構中。雌性寄生(sheng)(sheng)蜂通常(chang)會將幼卵(luan)注入毛(mao)毛(mao)蟲(chong)體內,當(dang)幼卵(luan)在(zai)毛(mao)毛(mao)蟲(chong)體內發(fa)育14天左右(you),就會變得非常(chang)難看。寄生(sheng)(sheng)蜂在(zai)毛(mao)毛(mao)蟲(chong)體內排(pai)卵(luan)發(fa)育是自(zi)然(ran)(ran)界(jie)中一(yi)種(zhong)奇特的(de)生(sheng)(sheng)物學攻(gong)擊(ji),寄生(sheng)(sheng)蜂幼卵(luan)使用其(qi)DNA中的(de)一(yi)種(zhong)病毒使毛(mao)毛(mao)蟲(chong)處于麻(ma)痹狀態。受(shou)傷(shang)的(de)毛(mao)毛(mao)蟲(chong)顯(xian)然(ran)(ran)被病毒所嚴重影響,它在(zai)幼卵(luan)旁建(jian)造了絲毯結構,對這些攻(gong)擊(ji)者進行防御,然(ran)(ran)而在(zai)這種(zhong)發(fa)育環境(jing)下,寄生(sheng)(sheng)蜂幼卵(luan)逐漸發(fa)育,最終(zhong)完全成熟,離開毛(mao)毛(mao)蟲(chong)飛(fei)向天空。