名稱:太白華陽龍(long)
拉丁學名:Huayangosaurus taibaii dong, et. al
體長:長4.3-4.5米
食性:柔(rou)軟多汁的植物(wu)
生(sheng)存年(nian)代:中侏羅世
地(di)質層位(wei):下沙溪(xi)廟組
生存地點(dian):中國(guo)自(zi)貢大(da)山鋪
辨認要訣(jue):肩(jian)上各有(you)一個的(de)棘刺
種類:劍(jian)龍類·華陽龍科
太(tai)白華(hua)陽(yang)龍(long)屬于極為(wei)原始型(xing)的(de)劍龍(long)類,大約(yue)4.3米長(chang),頭骨(gu)非常厚重而狹長(chang),像楔子(zi)狀。在頭骨(gu)上,存在有(you)二到三個眶(kuang)(kuang)上骨(gu);同時在顎上有(you)一(yi)個小(xiao)型(xing)的(de)眶(kuang)(kuang)前開孔;在大顎上又發育良好(hao)的(de)尺骨(gu)冠狀突(tu)起(qi),以(yi)及在上隅骨(gu)一(yi)個小(xiao)型(xing)后方孔。顎前排列(lie)有(you)六(liu)到七顆葉片(pian)狀小(xiao)齒。最引人入勝(sheng)的(de)背(bei)脊(ji)骨(gu)板,從頸項(xiang)到尾(wei)端對稱排列(lie),形狀稍(shao)異。而在肩部則有(you)一(yi)對特(te)大型(xing)的(de)骨(gu)板。總計大山鋪(pu)挖掘出(chu)12具(ju)華(hua)陽(yang)龍(long)的(de)個體(ti);完整的(de)兩具(ju)骨(gu)架(jia)經過復元(yuan)裝(zhuang)架(jia),分別陳列(lie)在自貢恐龍(long)博物(wu)館以(yi)及重慶博物(wu)館中。
太(tai)白(bai)華陽龍(long)(long)是(shi)一(yi)種中等大小(xiao)的原始劍(jian)龍(long)(long),這具(ju)標(biao)本是(shi)世(shi)界上發(fa)(fa)現的時代最早(zao)的完(wan)整劍(jian)龍(long)(long)骨(gu)架。它的發(fa)(fa)現為(wei)劍(jian)龍(long)(long)起源于(yu)東亞的理論提供了實證(zheng)。大山鋪的太(tai)白(bai)華陽龍(long)(long)標(biao)本有10余個,大部(bu)分(fen)被自貢恐龍(long)(long)博物館收(shou)藏(zang),已被整理和記錄的約有7個。它的正型標(biao)本為(wei)綜(zong)合骨(gu)架,包括一(yi)個吻部(bu)略受損的頭(tou)骨(gu)和一(yi)些零(ling)散不全的脊(ji)椎骨(gu)、四(si)肢骨(gu)及骨(gu)板(ban)。太(tai)白(bai)華陽龍(long)(long)也是(shi)侏羅紀中期(qi)地層中發(fa)(fa)現的劍(jian)龍(long)(long)中最完(wan)整的骨(gu)架。
小(xiao)型到中(zhong)等大(da)小(xiao)的劍龍類。頭骨(gu)(gu)(gu)大(da)而(er)厚重,前(qian)(qian)(qian)低后高(gao),呈楔形(xing)(xing)。前(qian)(qian)(qian)上(shang)(shang)(shang)(shang)頜(he)(he)骨(gu)(gu)(gu)與(yu)上(shang)(shang)(shang)(shang)頜(he)(he)骨(gu)(gu)(gu)之間存(cun)在一小(xiao)的橢(tuo)圓(yuan)(yuan)形(xing)(xing)凹。上(shang)(shang)(shang)(shang)顳孔之前(qian)(qian)(qian)的眶(kuang)(kuang)上(shang)(shang)(shang)(shang)骨(gu)(gu)(gu)內側突(tu)上(shang)(shang)(shang)(shang)有一小(xiao)的角(jiao)。顴(quan)骨(gu)(gu)(gu)發(fa)育(yu),上(shang)(shang)(shang)(shang)升突(tu)短(duan),后突(tu)伸長。眼眶(kuang)(kuang)之上(shang)(shang)(shang)(shang)具兩(liang)塊眶(kuang)(kuang)上(shang)(shang)(shang)(shang)骨(gu)(gu)(gu)。眼前(qian)(qian)(qian)孔大(da),呈三角(jiao)形(xing)(xing)。下頜(he)(he)厚實,前(qian)(qian)(qian)齒(chi)(chi)骨(gu)(gu)(gu)小(xiao),其上(shang)(shang)(shang)(shang)無牙齒(chi)(chi)。冠狀(zhuang)骨(gu)(gu)(gu)發(fa)育(yu)。下頜(he)(he)孔外孔小(xiao),三角(jiao)形(xing)(xing)。前(qian)(qian)(qian)上(shang)(shang)(shang)(shang)頜(he)(he)齒(chi)(chi)存(cun)在,且數量多(duo)達7枚(mei)。上(shang)(shang)(shang)(shang)頜(he)(he)齒(chi)(chi)至少28枚(mei),下頜(he)(he)齒(chi)(chi)骨(gu)(gu)(gu)齒(chi)(chi)至少27枚(mei)。所有頰齒(chi)(chi)葉片狀(zhuang),齒(chi)(chi)環(huan)不發(fa)育(yu),齒(chi)(chi)根圓(yuan)(yuan)錐(zhui)狀(zhuang)。頸椎(zhui)(zhui)8個(ge),背(bei)(bei)椎(zhui)(zhui)16個(ge)薦(jian)椎(zhui)(zhui)4個(ge)牢固愈合(he)在一起,背(bei)(bei)面(mian)未(wei)封(feng)閉(bi),可見(jian)三對(dui)薦(jian)孔。尾椎(zhui)(zhui)至少35個(ge)。前(qian)(qian)(qian)部背(bei)(bei)肋骨(gu)(gu)(gu)干(gan)后緣具有鉤(gou)狀(zhuang)突(tu)。肱骨(gu)(gu)(gu)略(lve)短(duan)于股骨(gu)(gu)(gu)。近排腕骨(gu)(gu)(gu)呈橢(tuo)球狀(zhuang),強烈愈合(he)一起。后腳第(di)Ⅱ、Ⅲ趾具有3個(ge)趾骨(gu)(gu)(gu)。恥骨(gu)(gu)(gu)前(qian)(qian)(qian)突(tu)短(duan)而(er)扁平,后突(tu)長而(er)呈竿狀(zhuang),末(mo)端膨大(da)與(yu)坐骨(gu)(gu)(gu)末(mo)端等齊拼合(he),膜(mo)質(zhi)骨(gu)(gu)(gu)板(ban)。