刀(dao)日春(chun)蜓(ting)(學(xue)名(ming):Nihonogomphus cultratus)是(shi)春(chun)蜓(ting)科、日春(chun)蜓(ting)屬昆(kun)蟲。雄性腹(fu)(fu)長36.5毫米,后(hou)(hou)(hou)翅23毫米。雌(ci)(ci)性腹(fu)(fu)長35毫米,后(hou)(hou)(hou)翅25毫米。雄性口器除下顎和上(shang)顎末(mo)(mo)(mo)端(duan)(duan)黑褐色外,全部黃綠色。臉在(zai)前(qian)額與(yu)后(hou)(hou)(hou)唇基(ji)(ji)之間的(de)(de)縫線中(zhong)央(yang)有(you)1個微(wei)(wei)細橫形(xing)黑斑(ban)。頭(tou)頂在(zai)單眼上(shang)方(fang)具1條橫脊(ji),后(hou)(hou)(hou)頭(tou)脊(ji)在(zai)前(qian)面(mian)觀(guan)中(zhong)央(yang)稍微(wei)(wei)下凹。前(qian)胸背(bei)板中(zhong)區中(zhong)央(yang)的(de)(de)雙斑(ban)甚大。足由基(ji)(ji)節至腿節末(mo)(mo)(mo)端(duan)(duan)約(yue)1/3處橘黃色,其余部分皆(jie)黑色。腹(fu)(fu)部第1、2節背(bei)中(zhong)條紋相連,甚闊。上(shang)肛(gang)附器外側緣有(you)3個黑色圓形(xing)小(xiao)(xiao)齒,背(bei)面(mian)觀(guan)上(shang)肛(gang)附器端(duan)(duan)部向(xiang)內呈(cheng)(cheng)三(san)角形(xing)擴大。陰囊(nang)末(mo)(mo)(mo)端(duan)(duan)生有(you)3個囊(nang)狀(zhuang)突起(qi),中(zhong)央(yang)的(de)(de)較小(xiao)(xiao);陽莖后(hou)(hou)(hou)葉側面(mian)觀(guan)呈(cheng)(cheng)水果刀(dao)狀(zhuang),該(gai)種(zhong)依此命名(ming);前(qian)鉤(gou)片(pian)的(de)(de)前(qian)支呈(cheng)(cheng)鐮刀(dao)狀(zhuang)鉤(gou)曲(qu),后(hou)(hou)(hou)支闕(que)如;后(hou)(hou)(hou)鉤(gou)片(pian)囊(nang)狀(zhuang),末(mo)(mo)(mo)端(duan)(duan)呈(cheng)(cheng)角狀(zhuang)突,朝向(xiang)向(xiang)中(zhong)的(de)(de)方(fang)向(xiang)鉤(gou)曲(qu)。雌(ci)(ci)性色彩與(yu)雄性基(ji)(ji)本相同。下生殖板較短,末(mo)(mo)(mo)端(duan)(duan)中(zhong)央(yang)有(you)1個大缺刻。
分布(bu)于中國河南(確山)。成蟲(chong)出現(xian)時間較早,4-5月可見。刀日春(chun)蜓(ting)一般(ban)在白(bai)晝活(huo)動于稚蟲(chong)生活(huo)的(de)環境附近。常在河塘、溪流(liu)處飛(fei)翔。刀日春(chun)蜓(ting)的(de)食物(wu)主要是蜉(fu)蝣稚蟲(chong)、蚊類幼蟲(chong)或同類的(de)其(qi)他個體,甚至蝌蚪(dou)及小魚。
稚(zhi)蟲(chong)棲息在(zai)水(shui)中(zhong)砂粒、泥(ni)水(shui)或(huo)水(shui)草(cao)間(jian),少數稚(zhi)蟲(chong)生(sheng)活在(zai)林地碎屑或(huo)積水(shui)的(de)樹(shu)洞中(zhong)或(huo)爬出水(shui)面附(fu)著在(zai)巖石的(de)水(shui)膜(mo)內(nei)。刀(dao)日(ri)春蜓一般在(zai)白晝活動于稚(zhi)蟲(chong)生(sheng)活的(de)環(huan)境附(fu)近。常在(zai)河塘(tang)、溪流(liu)處飛翔。雌性刀(dao)日(ri)春蜓喜(xi)歡待在(zai)遠離水(shui)源(yuan)的(de)地方,例如(ru)森林附(fu)近,它在(zai)那里更容易獲取(qu)食物。
分(fen)布于中(zhong)國河南(nan)(確山(shan))。
雄性腹長(chang)36.5毫(hao)米,后(hou)翅(chi)23毫(hao)米。雌性腹長(chang)35毫(hao)米,后(hou)翅(chi)25毫(hao)米。
雄性(xing)口(kou)器(qi)除下顎(e)和(he)上(shang)(shang)顎(e)末(mo)端(duan)(duan)(duan)黑(hei)(hei)(hei)褐色(se)(se)外(wai)(wai)(wai),全部(bu)(bu)(bu)(bu)黃(huang)(huang)綠色(se)(se);頭殼前(qian)(qian)面(mian)除上(shang)(shang)額后(hou)端(duan)(duan)(duan)和(he)頭頂(后(hou)緣(yuan)(yuan)除外(wai)(wai)(wai))黑(hei)(hei)(hei)色(se)(se)外(wai)(wai)(wai),亦全部(bu)(bu)(bu)(bu)黃(huang)(huang)綠色(se)(se)。臉(lian)在前(qian)(qian)額與后(hou)唇基之間的(de)縫線(xian)中(zhong)(zhong)央(yang)有(you)1個微(wei)細橫(heng)形(xing)黑(hei)(hei)(hei)斑(ban)(ban);頭殼后(hou)方除沿(yan)上(shang)(shang)眼眶(kuang)有(you)1條(tiao)(tiao)(tiao)(tiao)(tiao)(tiao)(tiao)黑(hei)(hei)(hei)色(se)(se)橫(heng)形(xing)闊(kuo)紋(wen)(wen)(wen)外(wai)(wai)(wai),余皆黃(huang)(huang)色(se)(se)。頭頂在單(dan)眼上(shang)(shang)方具1條(tiao)(tiao)(tiao)(tiao)(tiao)(tiao)(tiao)橫(heng)脊(ji),后(hou)頭脊(ji)在前(qian)(qian)面(mian)觀(guan)(guan)中(zhong)(zhong)央(yang)稍微(wei)下凹。前(qian)(qian)胸(xiong)(xiong)背(bei)板(ban)中(zhong)(zhong)區中(zhong)(zhong)央(yang)的(de)雙斑(ban)(ban)甚大(da),與側(ce)(ce)方甚大(da)黃(huang)(huang)斑(ban)(ban)相(xiang)(xiang)連(lian)。合(he)胸(xiong)(xiong)大(da)部(bu)(bu)(bu)(bu)分(fen)黃(huang)(huang)綠色(se)(se),領(ling)條(tiao)(tiao)(tiao)(tiao)(tiao)(tiao)(tiao)紋(wen)(wen)(wen)前(qian)(qian)方、合(he)胸(xiong)(xiong)脊(ji)上(shang)(shang)端(duan)(duan)(duan)及下端(duan)(duan)(duan)與領(ling)條(tiao)(tiao)(tiao)(tiao)(tiao)(tiao)(tiao)紋(wen)(wen)(wen)相(xiang)(xiang)連(lian),沿(yan)中(zhong)(zhong)胸(xiong)(xiong)側(ce)(ce)縫具1條(tiao)(tiao)(tiao)(tiao)(tiao)(tiao)(tiao)黑(hei)(hei)(hei)紋(wen)(wen)(wen),合(he)胸(xiong)(xiong)脊(ji)兩側(ce)(ce)和(he)沿(yan)中(zhong)(zhong)胸(xiong)(xiong)側(ce)(ce)縫黑(hei)(hei)(hei)線(xian)的(de)前(qian)(qian)方煙褐色(se)(se),合(he)胸(xiong)(xiong)側(ce)(ce)面(mian)第(di)2條(tiao)(tiao)(tiao)(tiao)(tiao)(tiao)(tiao)紋(wen)(wen)(wen)在氣(qi)門(men)以下和(he)甚細的(de)第(di)3條(tiao)(tiao)(tiao)(tiao)(tiao)(tiao)(tiao)紋(wen)(wen)(wen)黑(hei)(hei)(hei)色(se)(se)。肩前(qian)(qian)條(tiao)(tiao)(tiao)(tiao)(tiao)(tiao)(tiao)紋(wen)(wen)(wen)分(fen)離,肩前(qian)(qian)上(shang)(shang)點和(he)肩前(qian)(qian)下條(tiao)(tiao)(tiao)(tiao)(tiao)(tiao)(tiao)紋(wen)(wen)(wen)甚細,黑(hei)(hei)(hei)色(se)(se)。足由基節(jie)(jie)至腿節(jie)(jie)末(mo)端(duan)(duan)(duan)約(yue)1/3處橘黃(huang)(huang)色(se)(se),其余部(bu)(bu)(bu)(bu)分(fen)皆黑(hei)(hei)(hei)色(se)(se)。腹部(bu)(bu)(bu)(bu)第(di)1、2節(jie)(jie)背(bei)中(zhong)(zhong)條(tiao)(tiao)(tiao)(tiao)(tiao)(tiao)(tiao)紋(wen)(wen)(wen)相(xiang)(xiang)連(lian),甚闊(kuo),兩節(jie)(jie)側(ce)(ce)面(mian)包括(kuo)耳狀突(tu)黃(huang)(huang)色(se)(se);第(di)3-9節(jie)(jie)具背(bei)中(zhong)(zhong)條(tiao)(tiao)(tiao)(tiao)(tiao)(tiao)(tiao)紋(wen)(wen)(wen),第(di)3節(jie)(jie)條(tiao)(tiao)(tiao)(tiao)(tiao)(tiao)(tiao)紋(wen)(wen)(wen)長(chang)而寬闊(kuo),伸展全節(jie)(jie)長(chang),不與前(qian)(qian)后(hou)兩節(jie)(jie)背(bei)中(zhong)(zhong)條(tiao)(tiao)(tiao)(tiao)(tiao)(tiao)(tiao)紋(wen)(wen)(wen)相(xiang)(xiang)連(lian),第(di)4-7節(jie)(jie)背(bei)中(zhong)(zhong)條(tiao)(tiao)(tiao)(tiao)(tiao)(tiao)(tiao)紋(wen)(wen)(wen)縮短,為各節(jie)(jie)長(chang)的(de)2/3-1/2,基方較闊(kuo),向末(mo)端(duan)(duan)(duan)變尖,第(di)8、9節(jie)(jie)背(bei)中(zhong)(zhong)條(tiao)(tiao)(tiao)(tiao)(tiao)(tiao)(tiao)紋(wen)(wen)(wen)呈(cheng)(cheng)(cheng)1條(tiao)(tiao)(tiao)(tiao)(tiao)(tiao)(tiao)細線(xian),伸抵(di)該(gai)節(jie)(jie)全長(chang),第(di)3-7節(jie)(jie)均具腹緣(yuan)(yuan)條(tiao)(tiao)(tiao)(tiao)(tiao)(tiao)(tiao)紋(wen)(wen)(wen),第(di)8、9節(jie)(jie)兩側(ce)(ce)橘黃(huang)(huang)色(se)(se)斑(ban)(ban)甚大(da);第(di)10節(jie)(jie)橘黃(huang)(huang)色(se)(se),基端(duan)(duan)(duan)是1對(dui)黑(hei)(hei)(hei)斑(ban)(ban),端(duan)(duan)(duan)緣(yuan)(yuan)黑(hei)(hei)(hei)色(se)(se)。上(shang)(shang)肛(gang)(gang)附(fu)器(qi)、下肛(gang)(gang)附(fu)器(qi)均橘黃(huang)(huang)色(se)(se)。上(shang)(shang)肛(gang)(gang)附(fu)器(qi)外(wai)(wai)(wai)側(ce)(ce)緣(yuan)(yuan)有(you)3個黑(hei)(hei)(hei)色(se)(se)圓形(xing)小(xiao)齒,背(bei)面(mian)觀(guan)(guan)上(shang)(shang)肛(gang)(gang)附(fu)器(qi)端(duan)(duan)(duan)部(bu)(bu)(bu)(bu)向內呈(cheng)(cheng)(cheng)三角形(xing)擴(kuo)大(da),使(shi)上(shang)(shang)肛(gang)(gang)附(fu)器(qi)呈(cheng)(cheng)(cheng)1對(dui)“7”字形(xing),末(mo)端(duan)(duan)(duan)有(you)1個黑(hei)(hei)(hei)色(se)(se)小(xiao)齒;下肛(gang)(gang)附(fu)器(qi)長(chang)度約(yue)為上(shang)(shang)肛(gang)(gang)附(fu)器(qi)的(de)1/3,中(zhong)(zhong)央(yang)裂口(kou)呈(cheng)(cheng)(cheng)寬“U”形(xing)。陰囊末(mo)端(duan)(duan)(duan)生有(you)3個囊狀突(tu)起,中(zhong)(zhong)央(yang)的(de)較小(xiao),末(mo)端(duan)(duan)(duan)有(you)黑(hei)(hei)(hei)毛,兩側(ce)(ce)的(de)較大(da),3個突(tu)起之間為2條(tiao)(tiao)(tiao)(tiao)(tiao)(tiao)(tiao)凹槽,陽莖的(de)2鞭置放其中(zhong)(zhong);陽莖后(hou)葉(xie)側(ce)(ce)面(mian)觀(guan)(guan)呈(cheng)(cheng)(cheng)水果刀狀,該(gai)種依(yi)此命名(ming);前(qian)(qian)鉤(gou)片的(de)前(qian)(qian)支呈(cheng)(cheng)(cheng)鐮刀狀鉤(gou)曲,后(hou)支闕如;后(hou)鉤(gou)片囊狀,末(mo)端(duan)(duan)(duan)呈(cheng)(cheng)(cheng)角狀突(tu),朝向向中(zhong)(zhong)的(de)方向鉤(gou)曲。
雌(ci)性色彩(cai)與雄(xiong)性基本相同。下生殖板較短,末端中央有1個大缺刻。
成(cheng)蟲出現時(shi)間(jian)較早,4-5月可(ke)見。刀日春蜓一般以卵或(huo)稚蟲在水(shui)中(zhong)越冬(dong),少數(shu)(shu)種(zhong)類成(cheng)蟲也可(ke)冬(dong)眠。刀日春蜓屬(shu)不完全變態(tai)。生活(huo)史只(zhi)經(jing)卵、稚蟲和成(cheng)蟲3個階段(duan)。各階段(duan)歷期(qi)長短不同種(zhong)類間(jian)差異很大。卵經(jing)過5-230天孵化出包被在薄幾丁質膜鞘(qiao)中(zhong)的“預稚蟲”,經(jing)幾秒至數(shu)(shu)十分鐘(zhong)后,脫去(qu)膜鞘(qiao)進入第二齡期(qi),成(cheng)為能(neng)自由活(huo)動(dong)于水(shui)中(zhong)的稚蟲俗稱(cheng)水(shui)蠆(chai)。
刀(dao)日春蜓的(de)(de)食物(wu)主要是蜉蝣稚(zhi)蟲(chong)(chong)、蚊(wen)類(lei)幼蟲(chong)(chong)或同(tong)類(lei)的(de)(de)其(qi)他(ta)個體(ti),甚至蝌蚪及(ji)小(xiao)魚。稚(zhi)蟲(chong)(chong)期(qi)要經9-15齡才能發育成熟(shu)。老(lao)熟(shu)稚(zhi)蟲(chong)(chong)爬出(chu)水(shui)面,結束(shu)了水(shui)中生活,附(fu)著在石頭、植物(wu)或其(qi)他(ta)物(wu)體(ti)上,脫(tuo)去外殼進(jin)入成蟲(chong)(chong)期(qi)。剛出(chu)來的(de)(de)成蟲(chong)(chong)身體(ti)柔軟(ruan),要經過數小(xiao)時或幾晝夜時間硬(ying)化體(ti)殼,隨著體(ti)液循環,翅芽伸張挺直,體(ti)色與斑紋也逐漸鮮明,這(zhe)時刀(dao)日春蜓才有能力飛離(li)蛻皮處(chu),到廣闊天(tian)空中翱翔。
交尾:性(xing)成(cheng)熟的雄(xiong)(xiong)蟲(chong)在(zai)(zai)交尾前,先使腹(fu)部向(xiang)前彎(wan)(wan)曲,將第(di)9腹(fu)節生(sheng)殖孔移到第(di)2、3腹(fu)節下面與(yu)交合器的次生(sheng)陽(yang)莖(jing)對(dui)接,把精包(由帶狀(zhuang)(zhuang)黏膜把精子包纏(chan)卷裹(guo)形成(cheng))通過(guo)陽(yang)莖(jing)貯存于(yu)陰囊內(nei)。在(zai)(zai)完成(cheng)精子轉移之后(hou),雄(xiong)(xiong)蟲(chong)即在(zai)(zai)空中追逐雌(ci)蟲(chong),并用腹(fu)部末端的肛附器握住雌(ci)蟲(chong)的相關(guan)部位,雌(ci)蟲(chong)用六足抱住雄(xiong)(xiong)蟲(chong)的腹(fu)部,自動彎(wan)(wan)曲腹(fu)部,把腹(fu)端生(sheng)殖孔伸(shen)達雄(xiong)(xiong)蟲(chong)第(di)2節與(yu)次生(sheng)陽(yang)莖(jing)對(dui)接起來,形成(cheng)個環狀(zhuang)(zhuang)串連。
產卵:交尾結束后,雌蟲(chong)很快(kuai)產卵。卵產在植物體(ti)內或水中及(ji)其附(fu)近物體(ti)上。
刀日春蜓是有益(yi)于人類的(de)一(yi)類重要的(de)天敵昆蟲和(he)水質環境的(de)指示昆蟲。
列(lie)入《世界(jie)自然保護聯盟瀕危(wei)物種(zhong)紅色名錄》(IUCN 2007年(nian) ver 3.1)——無(wu)危(wei)(LC)。