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(shi)性:柔軟多(duo)汁的植物
生存(cun)年代:中侏(zhu)羅世(shi)
地質層位:下(xia)沙溪廟組
生存(cun)地點(dian):中國自貢大山鋪(pu)
辨認要訣:肩上各有一(yi)個的棘刺
種類(lei):劍龍類(lei)·華陽(yang)龍科(ke)
太白(bai)華(hua)陽龍(long)屬于極(ji)為原始型的劍龍(long)類,大約4.3米(mi)長,頭骨(gu)非常厚重而狹長,像楔子狀(zhuang)。在頭骨(gu)上(shang)(shang),存在有二到三個眶上(shang)(shang)骨(gu);同時在顎(e)上(shang)(shang)有一(yi)個小(xiao)型的眶前(qian)開孔(kong);在大顎(e)上(shang)(shang)又(you)發育(yu)良好的尺骨(gu)冠狀(zhuang)突起,以及(ji)在上(shang)(shang)隅骨(gu)一(yi)個小(xiao)型后(hou)方(fang)孔(kong)。顎(e)前(qian)排列(lie)有六到七顆葉片狀(zhuang)小(xiao)齒。最引人入勝的背脊骨(gu)板,從(cong)頸項到尾(wei)端對稱排列(lie),形(xing)狀(zhuang)稍異。而在肩部(bu)則有一(yi)對特大型的骨(gu)板。總(zong)計大山鋪挖掘出12具華(hua)陽龍(long)的個體;完整的兩(liang)具骨(gu)架(jia)經過復元裝架(jia),分別(bie)陳列(lie)在自貢恐龍(long)博物館以及(ji)重慶博物館中。
太(tai)白(bai)華陽(yang)龍(long)(long)(long)是(shi)一(yi)種中(zhong)等大(da)(da)小(xiao)的(de)(de)原(yuan)始劍龍(long)(long)(long),這具標本(ben)是(shi)世界上發現的(de)(de)時代(dai)最早的(de)(de)完(wan)整(zheng)(zheng)劍龍(long)(long)(long)骨架。它的(de)(de)發現為劍龍(long)(long)(long)起源于(yu)東亞(ya)的(de)(de)理論提供了實證。大(da)(da)山鋪的(de)(de)太(tai)白(bai)華陽(yang)龍(long)(long)(long)標本(ben)有(you)10余個,大(da)(da)部(bu)分被(bei)自貢恐龍(long)(long)(long)博物(wu)館收(shou)藏,已(yi)被(bei)整(zheng)(zheng)理和(he)記錄的(de)(de)約有(you)7個。它的(de)(de)正(zheng)型標本(ben)為綜(zong)合骨架,包括一(yi)個吻部(bu)略(lve)受損的(de)(de)頭骨和(he)一(yi)些零散(san)不全的(de)(de)脊(ji)椎骨、四肢骨及骨板。太(tai)白(bai)華陽(yang)龍(long)(long)(long)也是(shi)侏羅紀中(zhong)期地層中(zhong)發現的(de)(de)劍龍(long)(long)(long)中(zhong)最完(wan)整(zheng)(zheng)的(de)(de)骨架。
小(xiao)(xiao)(xiao)型到中等(deng)大小(xiao)(xiao)(xiao)的劍龍(long)類。頭骨(gu)大而厚(hou)重,前(qian)(qian)低后(hou)(hou)高,呈楔(xie)形(xing)。前(qian)(qian)上頜骨(gu)與(yu)(yu)上頜骨(gu)之(zhi)間存在(zai)一(yi)(yi)(yi)小(xiao)(xiao)(xiao)的橢(tuo)圓形(xing)凹。上顳孔(kong)(kong)之(zhi)前(qian)(qian)的眶(kuang)上骨(gu)內側(ce)突(tu)(tu)上有(you)一(yi)(yi)(yi)小(xiao)(xiao)(xiao)的角(jiao)。顴骨(gu)發(fa)育,上升突(tu)(tu)短(duan),后(hou)(hou)突(tu)(tu)伸長。眼眶(kuang)之(zhi)上具兩塊眶(kuang)上骨(gu)。眼前(qian)(qian)孔(kong)(kong)大,呈三角(jiao)形(xing)。下(xia)頜厚(hou)實,前(qian)(qian)齒(chi)(chi)骨(gu)小(xiao)(xiao)(xiao),其上無牙齒(chi)(chi)。冠狀(zhuang)(zhuang)骨(gu)發(fa)育。下(xia)頜孔(kong)(kong)外孔(kong)(kong)小(xiao)(xiao)(xiao),三角(jiao)形(xing)。前(qian)(qian)上頜齒(chi)(chi)存在(zai),且數量多達7枚(mei)。上頜齒(chi)(chi)至少28枚(mei),下(xia)頜齒(chi)(chi)骨(gu)齒(chi)(chi)至少27枚(mei)。所有(you)頰齒(chi)(chi)葉片狀(zhuang)(zhuang),齒(chi)(chi)環不發(fa)育,齒(chi)(chi)根圓錐狀(zhuang)(zhuang)。頸椎8個,背椎16個薦(jian)椎4個牢固愈合在(zai)一(yi)(yi)(yi)起,背面未封閉(bi),可見三對薦(jian)孔(kong)(kong)。尾椎至少35個。前(qian)(qian)部背肋骨(gu)干后(hou)(hou)緣(yuan)具有(you)鉤狀(zhuang)(zhuang)突(tu)(tu)。肱骨(gu)略短(duan)于股骨(gu)。近排腕骨(gu)呈橢(tuo)球狀(zhuang)(zhuang),強(qiang)烈愈合一(yi)(yi)(yi)起。后(hou)(hou)腳(jiao)第Ⅱ、Ⅲ趾具有(you)3個趾骨(gu)。恥骨(gu)前(qian)(qian)突(tu)(tu)短(duan)而扁平,后(hou)(hou)突(tu)(tu)長而呈竿(gan)狀(zhuang)(zhuang),末端膨大與(yu)(yu)坐(zuo)骨(gu)末端等(deng)齊(qi)拼合,膜(mo)質(zhi)骨(gu)板。