寄(ji)(ji)(ji)生(sheng)(sheng)(sheng)蜂(feng)(Parasitoid wasp),指膜(mo)翅目細腰亞(ya)目中(zhong)金小蜂(feng)科(ke)、姬蜂(feng)科(ke)、小蜂(feng)科(ke)等靠寄(ji)(ji)(ji)生(sheng)(sheng)(sheng)生(sheng)(sheng)(sheng)活的(de)(de)多種昆蟲。它們的(de)(de)寄(ji)(ji)(ji)生(sheng)(sheng)(sheng)方式很多,被寄(ji)(ji)(ji)生(sheng)(sheng)(sheng)對象從卵到(dao)成蟲的(de)(de)各個(ge)階段,都可能被寄(ji)(ji)(ji)生(sheng)(sheng)(sheng)。所謂寄(ji)(ji)(ji)生(sheng)(sheng)(sheng)蜂(feng),就是(shi)從植食性(xing)蜂(feng)類(lei)進化到(dao)筑巢性(xing)期(qi)間的(de)(de)一群肉食性(xing)蜂(feng)類(lei)。與寄(ji)(ji)(ji)生(sheng)(sheng)(sheng)蟲一樣。
分成外寄生和內(nei)寄生兩大類(lei)。前者是指把(ba)卵產在寄主(zhu)體表,讓(rang)孵化的幼蟲從體表取(qu)食(shi)寄主(zhu)身體;后者是把(ba)卵產在寄主(zhu)體內(nei),讓(rang)孵化的幼蟲取(qu)食(shi)害蟲體內(nei)的組織。內(nei)寄生形式者,被(bei)認為較為進化。
外(wai)(wai)寄(ji)(ji)(ji)生者在產卵(luan)(luan)前(qian),必須克服一件(jian)事,就是得(de)讓寄(ji)(ji)(ji)主(zhu)(zhu)無法動彈(dan),否則(ze)卵(luan)(luan)會(hui)被(bei)寄(ji)(ji)(ji)主(zhu)(zhu)壓壞,甚至被(bei)寄(ji)(ji)(ji)主(zhu)(zhu)咬死。因此(ci)(ci),外(wai)(wai)寄(ji)(ji)(ji)生蜂會(hui)先用產卵(luan)(luan)管(guan)蜇(zhe)刺寄(ji)(ji)(ji)主(zhu)(zhu),注(zhu)射有毒物質麻(ma)痹寄(ji)(ji)(ji)主(zhu)(zhu)。也就是說,產卵(luan)(luan)管(guan)除了產卵(luan)(luan)功能外(wai)(wai),兼具注(zhu)入麻(ma)醉液的(de)功能。此(ci)(ci)外(wai)(wai),還有一個待解決的(de)問(wen)題,就是寄(ji)(ji)(ji)主(zhu)(zhu)必須有造繭性(xing)等隱蔽身體(ti)的(de)習性(xing),因為寄(ji)(ji)(ji)主(zhu)(zhu)若遭麻(ma)醉,行動變(bian)得(de)遲鈍(dun),容易(yi)受到敵(di)害攻擊(ji)或其他外(wai)(wai)在環境的(de)傷害,如果沒有隱蔽自己的(de)絕活(huo),體(ti)表的(de)寄(ji)(ji)(ji)生蜂幼蟲也將會(hui)與它同歸于(yu)盡。而采(cai)用內寄(ji)(ji)(ji)生方式(shi)的(de)寄(ji)(ji)(ji)生蜂,問(wen)題就沒有那么(me)嚴重。
此外(wai),也有(you)像蜘(zhi)(zhi)(zhi)蛛姬蜂(feng)這(zhe)類具有(you)產卵特技寄(ji)生蜂(feng),它(ta)們以(yi)蜘(zhi)(zhi)(zhi)蛛網上的蜘(zhi)(zhi)(zhi)蛛為(wei)寄(ji)主。當它(ta)突(tu)襲蜘(zhi)(zhi)(zhi)蛛時,會先刺(ci)蜇(zhe)蜘(zhi)(zhi)(zhi)蛛腳(jiao)(jiao)的基部(bu),利(li)用其暫時失去感覺之際(ji),在它(ta)的頭(tou)胸部(bu)或腹部(bu)腹面產下一粒卵,蜘(zhi)(zhi)(zhi)蛛后來雖然恢復知覺,但由于腳(jiao)(jiao)摳不到卵,只好(hao)任由孵(fu)化的姬蜂(feng)幼蟲吸血,而終至死亡(wang)。
寄(ji)生蜂(feng)的種類很多,分別寄(ji)生于寄(ji)主的不同(tong)發育(yu)階段,常見(jian)的有小蜂(feng)、姬蜂(feng)、繭蜂(feng)、赤眼(yan)蜂(feng)、嚙小蜂(feng)等。
姬(ji)蜂(feng)(feng)(feng)(feng)是(shi)(shi)膜(mo)翅(chi)(chi)(chi)(chi)目(mu)姬(ji)蜂(feng)(feng)(feng)(feng)科的(de)(de)(de)(de)(de)(de)一(yi)(yi)種(zhong)(zhong)寄(ji)(ji)生(sheng)(sheng)蜂(feng)(feng)(feng)(feng),膜(mo)翅(chi)(chi)(chi)(chi)目(mu)(Hymenoptera)姬(ji)蜂(feng)(feng)(feng)(feng)科(Ichneunmonidae,有(you)(you)(you)(you)(you)重要經濟意義的(de)(de)(de)(de)(de)(de)一(yi)(yi)個(ge)大(da)科)昆(kun)蟲(chong)(chong)(chong)。分布(bu)很廣,約40,000種(zhong)(zhong)。形狀、顏色、大(da)小(xiao)各異,一(yi)(yi)般1.2公(gong)分(約0.5寸(cun))長(chang)。北(bei)美洲最長(chang)的(de)(de)(de)(de)(de)(de)長(chang)針姬(ji)蜂(feng)(feng)(feng)(feng)屬達5公(gong)分。許多(duo)(duo)種(zhong)(zhong)的(de)(de)(de)(de)(de)(de)腹(fu)部細長(chang)而彎曲(qu),像黃蜂(feng)(feng)(feng)(feng),區別一(yi)(yi)般在于觸角較長(chang),節較多(duo)(duo)。產(chan)(chan)卵(luan)(luan)器通常(chang)比(bi)身體(ti)長(chang)。許多(duo)(duo)種(zhong)(zhong)的(de)(de)(de)(de)(de)(de)前翅(chi)(chi)(chi)(chi)有(you)(you)(you)(you)(you)一(yi)(yi)黑點(dian)。寄(ji)(ji)生(sheng)(sheng)在蜘蛛以及多(duo)(duo)類(lei)昆(kun)蟲(chong)(chong)(chong)上(shang),尤其(qi)是(shi)(shi)鱗(lin)翅(chi)(chi)(chi)(chi)目(mu)和其(qi)他(ta)膜(mo)翅(chi)(chi)(chi)(chi)目(mu)昆(kun)蟲(chong)(chong)(chong)。由(you)于寄(ji)(ji)生(sheng)(sheng)在許多(duo)(duo)害蟲(chong)(chong)(chong)上(shang),總(zong)的(de)(de)(de)(de)(de)(de)來說是(shi)(shi)益蟲(chong)(chong)(chong)。雌蜂(feng)(feng)(feng)(feng)在宿主的(de)(de)(de)(de)(de)(de)幼(you)蟲(chong)(chong)(chong)或蛹(yong)(很少在卵(luan)(luan)或成(cheng)體(ti))上(shang)產(chan)(chan)卵(luan)(luan)。幼(you)蟲(chong)(chong)(chong)取食(shi)宿主的(de)(de)(de)(de)(de)(de)脂肪(fang)和體(ti)液,長(chang)成(cheng)后(hou)織一(yi)(yi)繭。如果(guo)宿主生(sheng)(sheng)活場所(suo)(suo)不(bu)是(shi)(shi)隱蔽(bi)的(de)(de)(de)(de)(de)(de),則通常(chang)寄(ji)(ji)生(sheng)(sheng)在宿主體(ti)內;若宿主生(sheng)(sheng)活在隱蔽(bi)處(如樹木孔道(dao)內),則常(chang)寄(ji)(ji)生(sheng)(sheng)在宿主體(ti)姬(ji)蜂(feng)(feng)(feng)(feng)外。一(yi)(yi)個(ge)宿主上(shang)多(duo)(duo)數只有(you)(you)(you)(you)(you)一(yi)(yi)個(ge)幼(you)蟲(chong)(chong)(chong),但有(you)(you)(you)(you)(you)時也(ye)可有(you)(you)(you)(you)(you)多(duo)(duo)個(ge)幼(you)蟲(chong)(chong)(chong)寄(ji)(ji)生(sheng)(sheng)。赤眼(yan)蜂(feng)(feng)(feng)(feng)以眼(yan)紅色而得名,它(ta)經常(chang)把卵(luan)(luan)產(chan)(chan)在松(song)毛蟲(chong)(chong)(chong)、玉米(mi)螟(ming)(ming)、二化螟(ming)(ming)及甘蔗螟(ming)(ming)的(de)(de)(de)(de)(de)(de)卵(luan)(luan)中(zhong),幼(you)蟲(chong)(chong)(chong)就(jiu)以寄(ji)(ji)生(sheng)(sheng)卵(luan)(luan)中(zhong)的(de)(de)(de)(de)(de)(de)營養物質為(wei)食(shi),所(suo)(suo)以可以大(da)量消(xiao)(xiao)滅(mie)農(nong)林害蟲(chong)(chong)(chong);雌馬尼蜂(feng)(feng)(feng)(feng)可以把卵(luan)(luan)產(chan)(chan)在鉆入樹皮(pi)(pi)的(de)(de)(de)(de)(de)(de)天(tian)牛(niu)幼(you)蟲(chong)(chong)(chong)體(ti)內,以后(hou)它(ta)的(de)(de)(de)(de)(de)(de)幼(you)蟲(chong)(chong)(chong)便(bian)(bian)以天(tian)牛(niu)幼(you)蟲(chong)(chong)(chong)為(wei)食(shi),直至吃得只剩一(yi)(yi)層皮(pi)(pi)。當它(ta)發現(xian)鱗(lin)翅(chi)(chi)(chi)(chi)目(mu)幼(you)蟲(chong)(chong)(chong)后(hou)便(bian)(bian)落到它(ta)的(de)(de)(de)(de)(de)(de)頭(tou)部,用長(chang)針狀的(de)(de)(de)(de)(de)(de)產(chan)(chan)卵(luan)(luan)器刺入其(qi)腦部,實施(shi)麻碎(sui)后(hou)被寄(ji)(ji)生(sheng)(sheng)幼(you)蟲(chong)(chong)(chong)便(bian)(bian)昏(hun)迷不(bu)醒,然后(hou)被“劫”入穴(xue)中(zhong),產(chan)(chan)卵(luan)(luan)其(qi)中(zhong);其(qi)他(ta)如金小(xiao)蜂(feng)(feng)(feng)(feng)、姬(ji)蜂(feng)(feng)(feng)(feng)、小(xiao)繭蜂(feng)(feng)(feng)(feng)等是(shi)(shi)消(xiao)(xiao)滅(mie)害蟲(chong)(chong)(chong)的(de)(de)(de)(de)(de)(de)能手。左圖是(shi)(shi)用赤眼(yan)蜂(feng)(feng)(feng)(feng)防治玉米(mi)螟(ming)(ming),掛在玉米(mi)葉子上(shang)是(shi)(shi)赤眼(yan)蜂(feng)(feng)(feng)(feng)的(de)(de)(de)(de)(de)(de)卵(luan)(luan)塊,每個(ge)小(xiao)白球里有(you)(you)(you)(you)(you)40多(duo)(duo)個(ge)赤眼(yan)蜂(feng)(feng)(feng)(feng)卵(luan)(luan)。
黑青小蜂(Dibrachys xavus)棉紅(hong)(hong)鈴(ling)蟲(chong)等的(de)(de)天敵,金(jin)小蜂科。雌成蟲(chong)體(ti)長(chang)約2.8毫米,黑色(se),翅透(tou)明有(you)金(jin)屬光澤,腹部紡錘形。雄成蟲(chong)體(ti)長(chang)約2毫米,腹部第一、二節間(jian)有(you)半透(tou)明的(de)(de)黃白色(se)帶。年生(sheng)11-12代(dai)。在越冬結(jie)繭的(de)(de)棉紅(hong)(hong)鈴(ling)蟲(chong)幼蟲(chong)體(ti)上寄生(sheng),使其死亡。用于(yu)防治棉花倉(cang)庫(ku)內(nei)的(de)(de)棉紅(hong)(hong)鈴(ling)蟲(chong),倉(cang)庫(ku)內(nei)放蜂后,寄生(sheng)率很高。
與捕(bu)食(shi)性(xing)昆蟲(chong)不同的是(shi),寄(ji)生性(xing)昆蟲(chong)一(yi)般都是(shi)成(cheng)蟲(chong)積極地尋找(zhao)寄(ji)主(zhu)(zhu)(zhu)(zhu)(zhu),當發現寄(ji)主(zhu)(zhu)(zhu)(zhu)(zhu)后,將卵產(chan)于體內。幼蟲(chong)孵化后取食(shi)寄(ji)主(zhu)(zhu)(zhu)(zhu)(zhu)的營養,和(he)寄(ji)主(zhu)(zhu)(zhu)(zhu)(zhu)共生一(yi)段時間后才使寄(ji)主(zhu)(zhu)(zhu)(zhu)(zhu)死亡(wang)。幼蟲(chong)不能(neng)主(zhu)(zhu)(zhu)(zhu)(zhu)動尋找(zhao)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)(sheng)蜂(feng)通常(chang)會將幼(you)卵(luan)(luan)(luan)注入毛(mao)毛(mao)蟲(chong)體內,當幼(you)卵(luan)(luan)(luan)在(zai)(zai)毛(mao)毛(mao)蟲(chong)體內發(fa)(fa)(fa)育(yu)14天左右,就會變得非(fei)常(chang)難看(kan)。寄生(sheng)(sheng)(sheng)蜂(feng)在(zai)(zai)毛(mao)毛(mao)蟲(chong)體內排卵(luan)(luan)(luan)發(fa)(fa)(fa)育(yu)是自然(ran)界中(zhong)一種(zhong)奇特的生(sheng)(sheng)(sheng)物學攻擊,寄生(sheng)(sheng)(sheng)蜂(feng)幼(you)卵(luan)(luan)(luan)使用其DNA中(zhong)的一種(zhong)病毒(du)使毛(mao)毛(mao)蟲(chong)處于(yu)麻(ma)痹狀態。受傷的毛(mao)毛(mao)蟲(chong)顯然(ran)被病毒(du)所嚴重(zhong)影(ying)響,它(ta)在(zai)(zai)幼(you)卵(luan)(luan)(luan)旁建造了絲毯(tan)結構,對(dui)這些攻擊者進行防(fang)御(yu),然(ran)而(er)在(zai)(zai)這種(zhong)發(fa)(fa)(fa)育(yu)環(huan)境下(xia),寄生(sheng)(sheng)(sheng)蜂(feng)幼(you)卵(luan)(luan)(luan)逐(zhu)漸發(fa)(fa)(fa)育(yu),最終完全成熟,離開(kai)毛(mao)毛(mao)蟲(chong)飛向天空(kong)。