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Table 2 Vertebral information and congenital abnormalities in investigated mammalian specimens: Trichechidae (manatees)

From: Breaking evolutionary and pleiotropic constraints in mammals: On sloths, manatees and homeotic mutations

Trichechidae (manatees)
Collection Species Collection No. Sex Vertebral formula Precaudal No. Rud. ribs on vertebrae Skeletal and fibrous abnormalities
RBINC   1,181 n.a. 6C 17T 1T/Cd 26Cd 23.5 V24 V7-V8 fusion, sternal foramen and asymmetric sternum.
   U. Nat coll. n.a. 5C 2C/T 17T 2+Cd 24 V6, V7 Abnormal fibrous band sfrom rudimentary rib to sternum and rostral to sternum, sternal foramen
   RMNH.MAM.16050 M 4C 2C/T 17T 26Cd 23 V5, V6 Asymmetric sternum, cervical spinous processes reduced and not fused
   RMNH.MAM.24221 **) F 5C 1C/T 17T 1T/Cd 24Cd 23.5 V6, V24 Sternal foramen and asymmetric sternum, cervical spinous processes reduced and not fused
   RMNH.MAM.16049 M 5C 1C/T 16T 1T/Cd 26Cd 22.5 V6, V23 -
   RMNH.MAM.22392 F 4C 2C/T 16T 1T/Cd 26Cd 22.5 V5, V6, V23 Sternal foramen and asymmetric sternum, malformed cervical vertebrae
  Trichechus manatus ZMA.10725 n.a. 5C 1C/T 17T 25Cd 23 V6 Sternal foramen and asymmetric sternum and asymmetric pelvic rudiments
NCBN   ZMA.9550 n.a. 5C 1C/T 16T 17+Cd 22 V6 C2-C3 fusion, malformed cervical vertebrae
   ZMA.9549 F 5C 1C/T 16T 1T/Cd 26Cd 22.5 V6, V23 Sternal foramen and asymmetric sternum, malformed caudal ribs
   ZMA.23909 **) n.a. 5C 1C/T 16T 1T/Cd 25Cd 22.5 V6,V23 Sternal foramen and asymmetric sternum
   ZMA.1342 **) M 5C 1C/T 15T 24Cd 21 V6 Sternal foramen, malformed cervical vertebrae
   ZMA.1340 n.a. 5C 1C/T 17T 23+Cd 23 V6 Abnormal fibrous band from rudimentary rib to sternum and rostral to sternum
   ZMA.26773 n.a. 5C 1C/T 17T 1T/Cd 13+Cd 23.5 V6, V24 Asymmetric sternum
   U. Nat coll. n.a. 6C 17T 2Cd 23 - C2-C3 fusion, asymmetric sternum.
   ZMA.14042 M 5C 1C/T 17T 26Cd 23 V6 C2-C3 fusion, asymmetric sternum.
NHM Trichechus senegalensis 1999.77 n.a. 6C 16T - - C2-C3 fusion, asymmetric ribs, deformation of scapula and limbs
   1864.12.1 n.a. 5C 1C/T 15T 1T/Cd 26Cd 21.5 V6, V22 C2-C3 fusion
RMCA   21530 F 5C 1C/T 17T 27Cd 23 V6 C3-C4 fusion.
  1. *) Skeleton largely absent
  2. **) Died in captivity
  3. Abbreviations: n.a. - not available, C -Cervical, T - Thoracic, L-Lumbar, S - Sacral, Cg - Coccygeal, Cd - Caudal (post thoracic), V - Vertebra, rud. - rudimentary, NCBN - NCB Naturalis, RMCA - Royal Museum for Central Africa Tervuren, RBINC - Royal Belgian Institute of Natural Sciences Brussels, NHM - Natural History Museum London