採樣區域 (圖. 1) 包括了以下地區: El Mamon,´ T´ıo Gregorio,Corralito and El Hatillo, all north of the town of Urumaco, Falco´n State, northwestern Venezuela. 法爾科州的烏魯馬科鎮北部和委內瑞拉的西北部 Specimens were obtained from the middle and upper members of the UrumacoFormation. 化石標本取自於烏魯馬科地表層的中上段。 The middle member of the Urumaco Formation con- sists mostly of claystoneand sand. 烏魯馬科中部的地表層由粘土岩和沙組成。 The grey claystone yields microfossils and the brown claystone containsvertebrate re- mains such as reptiles, 脊椎動物和爬行動物的化石含有灰色黏土岩和褐色粘土岩。 mammals, marine and freshwater fish, as well as coprolites and wood (D´ıaz de Gamero & Linares 1989; Aguilera 2004). 哺乳動物，海洋魚類和淡水魚，以及糞化石和木化石（加梅羅&利納雷斯1989；阿奎萊拉2004） The sandy beds range from shelly sandstones to consolidated coquinalimestone. 沙床的範圍從貝殼砂岩到混合貝殼砂岩 In the lower half of this middle member there is an abundant and di-verse marine fish and mollusc fauna in a sandy matrix. 在烏魯馬科中部的地下層有一層琳琅滿目的海洋魚類和軟體動物的沙質基質。 The palaeoenvironments are interpreted as inner sublittoral and coastallagoon with riverine and estuarine influence (D´ıaz de Gamero 1996; Aguilera 2004). 古環境將其解釋為河口水體淺海內部和瀉湖沿岸的影響（加梅羅1996；阿奎萊拉2004）。 The upper member of the Urumaco Formation also comprises grey tobrown, often limey claystones with thin intercalated and locally shellysandstones. 烏魯馬科的地表層還包括灰色的英國粘土岩和棕色的本地砂岩。 The uppermost layer is referred to as the ‘capa de tortugas’ because of its abundantremains of Bairdemys turtles (D´ıaz de Gamero &Linares 1989). 最淺表的一層被稱為“卡帕龜群島”，因為這兒有著數不勝數的貝爾德邁烏龜。（加梅羅&利納雷斯1989） Several localities and levels have concen- trations of vertebrate fossils. 一些的位置和地層的脊椎動物化石比較集中。 The vertebrate fauna includes marine, estuarine and freshwater fishes,terrestrial, freshwater and marine turtles and crocodilians and terrestrial andaquatic/semiaquatic mammals (Sa´nchez-Villagra et al.2003; Aguilera 2004). 脊椎動物包括海洋、河口和淡水魚類，淡水和海洋海龜、鱷魚和陸地和水生或半水棲哺乳動物。（SA´桑切斯比利等。2003；阿奎萊拉2004。） The palaeoenvironments were tropical near- shore marine to low coastalsavannas with freshwater rivers. 海岸附近的古環境是熱帶海洋性氣候與熱帶稀樹草原氣候 For additional information about these geological units see Ministerio deEnerg´ıa y Minas (1997). 如果想了解更多地質單元相關信息的話，請看到米呢斯特德恩爾吉雅米納斯(1997). A complete list of the fossil fauna from the Urumaco Formation has beenrecently summarised in Sa´nchez-Villagra et al.(2003) and Aguilera (2004). 烏魯馬科完整的動物化石群列表最近已在沙縣´桑切斯比利（2003）及阿奎萊拉（2004）等地區匯總。 A late Miocene age for the UrumacoFormation is indicated by foraminiferans, while the mammals suggest a SouthAmerican land mammal age between Chasicoan and Huayquerian (D´ıaz de Gamero & Linares 1989), or ap- proximately 9Ma (Marshall & Sempere 1993). 中新世晚期烏魯馬科的地表層有孔蟲的跡象，而哺乳動物表明南美洲的陸生哺乳動物時代介於查斯科恩時期和哈奇雷恩時期之間 加梅羅&利納雷斯1989），或大約9Ma（馬歇爾 &森佩雷1993）。 Systematic palaeontology 古生物學 CROCODYLIFORMES (Benton & Clark, 1988) 鱷形動物（本頓&克拉克，1988） ALLIGATORIDAE Gray, 1844 短吻鱷科 格拉伊，1844 PURUSSAURUS Barbosa-Rodrigues, 1892 TYPE SPECIES. Purussaurus brasiliensis Barbosa-Rodrigues1892.普魯斯鱷巴博薩-羅德里格斯，1892種類型。巴西普魯斯鱷巴博薩-羅德里格斯1892。 DIAGNOSIS. Giant alligatorids with enlarged and wide skull; 鑑定：巨型短吻鱷頭骨寬大 snout tip rounded and ornamented with coarse reticulating ridges andpits; 短吻鱷的鼻子尖圓，且有粗網狀隆起和凹坑 long and wide narial aperturesurrounded by a large narial fossa formed by developed rostral canthi thatextend posteriorly to the prefrontal–frontalcontact; 短吻鱷鼻孔的孔徑長而寬，寬大的鼻孔由嘴角延伸至的眼角，一直向後延伸至延髓前額葉； oval incisive foramen entirelysurrounded by the premaxillae; 前頜骨將橢圓形的切牙孔完全包圍。 nasal and lacrymal bones not in contact; 鼻骨與淚骨不相連；上顳骨空寬大；鱗狀骨尾部高而長 large supratemporal fenestra; squamosal high and longposteriorly; nasal and frontal bones separated by the prefrontal bones; 額前骨將鼻骨和額骨分開。 posterior dorsal margin of the skull table (squamosal and supraoccipital)strongly concave.頭表骨的後脊（鱗狀骨和枕骨）嚴重彎曲 REMARKS. This genus was erected by Barbosa-Rodrigues (1892), 評論with type species Purussaurus brasiliensis, 根據巴西亞馬遜普魯斯河的一個下頜骨碎片，可以得出這種生物是巴博薩-羅德里格斯（1892），品種為巴西普魯斯鱷。 on the basis of a fragmented mandible from the Amazon Purus river in Brasil. However, his holotype was subsequently lost 但是這些珍貴的正型標本後來丟失了（Price, 1967）。 Gervais (1876) had earlier described the species Dinosuchus terror basedon a large vertebra collected from the Amazon. 早在1876年，有人根據在亞馬遜河發現一些巨大椎骨命名（Gervais,1876）的“恐怖鱷屬”（"Dinosuchus"）的屬型種“駭人恐怖鱷” Mook (1921) subsequently described a large Colombian alligatorid mandibleas Dinosuchus neivensis and a deformed Amazon symphysis toothed mandible(Langston 1965; Price 1967) 而哥倫比亞發現的一個大型“短吻鱷類”下頜INGEOMINAS, DHL-45，最初被歸入“恐怖鱷屬”，命名（Mook, 1941）為內華“恐怖鱷”（"Dinosuchus"neivensis），後來改為巴西普魯斯鱷。as Brachygnathosuchusbraziliensis. Nopcsa (1924), however, recognisedthat the three taxa (Brachygnathosuchus braziliensis, Purussaurus brasili-ensis and Dinosuchus neivensis) were synonymous, keeping Purussaurus as thesenior synonym by date priority. “巴西短頜鱷”（"Brachygnathosuchus braziliensis"Mook, 1921）和“駭人恐怖鱷”（Dinosuchus terror），以及巴西普魯斯鱷是同一種生物，其中巴西普魯斯鱷出現的時間最早。 Langston (1965)reviewed the Colombian specimens and concluded thatDinosuchus terror is a nomen vanum and renamed the Colombian species Caimanneivensis. 考古學家把哥倫比亞標本萊斯頓（1965）進行了複審,並指出“駭人恐怖鱷”更名為哥倫比亞凱門鱷。 Patterson (1936, 1943) recognised Purussaurus as a synonym of Caiman. 根據標本帕特森（1936，1943）可以確定普魯斯鱷就是凱門鱷。 More recently, Bocquentin-Villanueva et al. (1989) compared an additionalskull and associated mandible from the Urumaco Formation (Venezuela) 近來，考古學家將烏魯馬科地層Bocquentin-Villanueva等化石標本的另外一個頭骨和相關的下頜骨作比較。 and the Solimo˜es Formation (Brasil) andreerected the genus Purussaurus with the two species P. brasiliensis Barbosa-Rodrigues, 1892 and P. neivensis (Mook, 1941). 巴西亞馬遜河流 Solimo˜es地層的化石標本重建了普魯斯鱷巴博薩-羅德里格斯和“駭人恐怖鱷”的聯繫。 Purussaurus mirandai sp. nov. (Figs 2–4,7 A-C)
化石
1989 Purussaurus sp.Bocquentin-Villanueva et al.: 427–438, figs 1, 2. 2003 Purussaurus sp. Sa´nchez-Villagra et al.: 15. 2004 Purussaurus sp. Aguilera: 90–92. ETYMOLOGY. After Francisco de Miranda, from whom the University in Corois named, in recognition of his historical contributions to the HispanoAmerican independence. 詞源 之後，為了紀念他在西班牙裔美國人的獨立中做出的歷史貢獻，人們將克羅的大學命名為弗朗西斯科德米蘭。 TYPE SPECIMENS. Holotype:UNEFM-CIAAP-1369, a com- plete skull with associated mandibles, 標本類型 正模標本：UNEFM-CIAAP-1369， J. Bocquentin Villanueva在埃爾阿蒂約收集了完整的頭骨和下頜骨，股骨和坐骨。 femur and is- chium, collected in 1987 by J. Bocquentin-Villanueva at El Hatillo. Paratypes: AMU-CURS-135 (a skull with associ- ated mandibles), ElHatillo; MCC URU-115-72V (premax- illa and maxilla), El Picache; MCCURU-157-72V (dentary), T´ıo Gregorio; UNEFM-CIAAP-1445,(right mandible), El Hatillo. 副模標本：AMU-CURS-135 （頭骨和下頜骨），ElHatillo; MCC URU-115-72V （前頜骨和上頜骨），El Picache; MCCURU-157-72V （ [脊椎] 齒骨），T´ıo Gregorio; UNEFM-CIAAP-1445, (右頜骨), El Hatillo. OTHER MATERIAL EXAMINED. 其他標本的研究 AMU-CURS-33 (isolated posteriortooth), AMU-CURS-33（獨立的後牙） T´ıo Gregorio; AMU-CURS-57 (mand ible), T´ıo Gregorio; AMU-CURS-57 (下頜骨), T´ıo Gregorio; MCC URU-76-72V (mandible), T´ıo Gregorio; MCC URU-76-72V (下頜骨), 0.5 km north of quebrada El Picache and 50 m east of Chiguaje fault;UNEFM-CIAAP-1363 (pubis), UNEFM-CIAAP-1367 uebrada El Picache 以北0.5km，Chiguaje斷層以東50m.UNEFM-CIAAP-1363(恥骨)UNEFM-CIAAP-1367 quebrada El Picache and 50 m east of Chiguaje fault; UNEFM-CIAAP-1363(pubis), UNEFM-CIAAP-1367 (scapula, coracoid and ilium), UNEFM-CIAAP-1370 (humerus), El Hatillo. (肩胛骨, 喙骨和髂骨),UNEFM-CIAAP-1370 (肱骨), El Hatillo. OCCURRENCE. All specimens come from the upper Miocene Urumaco Formation,Falco´n State, northwestern Venezuela. 發現 所有標本來自第三紀中新世委內瑞拉西北部，法爾科州的烏魯馬科地層。 DIAGNOSIS. Skull large, elongatedand much flatter than in P. brasiliensis and P. neivensis. 鑑定 頭骨大而延長，普魯斯鱷的頭骨比短吻鱷和凱門鱷更平坦 Snout with an elongated median depression, wider than in P. brasiliensisand P. neivensis, 普魯斯鱷的鼻子長且中間凹陷，鼻部也比短吻鱷和凱門鱷更寬 and with very large narial opening, almost 60% of rostrallength. 鼻孔張開得非常大，是普魯斯鱷嘴部長度的百分之六十。 Premaxilla and maxilla suture extend posteriorly onthe ventral skull surface, 前頜骨和上頜骨縫合線向後延伸至腹側顱骨表面 with premaxillary bones extending posteriorly to the fourth maxillaryalveolus, 與前頜骨後方延伸到上頜骨的第四個小孔 while the inverted ‘V’ sutureshape on the palatal face reaches the fifth maxillary tooth level. 而該化石標本呈倒“V”形，上顎骨縫合線的交匯處有五顆上頜齒。 On the dorsal skull surface, premaxillae extend up to the lateral marginsof the narial depression. 在背側顱骨表面，前頜骨延長到鼻孔的外沿的凹陷處。 Premaxillae bear a large incisive foramen thatextends anteriorly between the occlusive fossae for the first mandibular teeth,not so further前頜骨承受較大的切牙孔，剛好向前延伸至第一個下頜牙咬合的凹槽之間。
米蘭達UNEFM-CIAAP 1369的頭骨最大長度1260mm，巴西的UFAC 1403頭骨最大長度1400mm，米蘭達比巴西短了140mm，而吻部長度是巴西910mm，米蘭達770mm，因此巴西多出來的是上頜骨和吻部(大鼻子)，當然米蘭達這個個體頭骨比巴西細很多, 685 vs 820mm, (巴西這個個體算是一個比較粗的，1400mm對應820mm寬度, UFAC的頭骨上限長度接近，寬度只有765~800mm). MCNC-URU-158-72V是頭骨根據右側的腹面圖，保守估測是巴西最大個體DGM R 572(按840mm寬度)計算，比例是690mm vs 718.5mm, 巴西略寬. 對齊上頜骨之後，巴西只是前上頜骨長了75mm，米蘭達頭骨按照比例(1540-75)*(690/718.5)=1406, 如果巴西按820mm寬度計算，則是701mm，米蘭達頭骨長度是1442mm 下頜骨，對其第5顆牙之後發現，兩者5~14顆保留位置的齒床長度相等，同樣位置的寬度是560mm vs 570mm。，下頜骨因為凸出的D1牙槽而長了3cm，其餘基本相等。
