I'm not 100% sure yet but I'll keep looking!

Overlying the boney elements are a series of scutes, which are made of keratin and are a lot like horn or nail tissue. In the center of the carapace are 5 vertebral scutes and out from these are 4 pairs of costal scutes. Around the edge of the shell are 12 pairs of marginal scutes. All these scutes are aligned so that for the most part the sutures between the bones are in the middle of the scutes above. At the anterior of the shell there may be a cervical scute (sometimes incorrectly called a nuchal scute) however the presence or absence of this scute is highly variable, even within species.

https://en.wikipedia.org/wiki/Turtle_shell

Nombres de los escudos de las tortugas
El caparazón de las tortugas está divido en numerosos escudos rígidos que protegen el hueso (el caparazón está formado por huesos y, encima de éstos, escudos). Según la especie pueden tener más o menos escudos en distintas partes de su caparazón, incluso existen especies sin ningún escudo (tortugas de caparazón blando, Trionychidae y Carettochelyidae).

Distinguiremos entre los escudos del caparazón y del plastrón:

Escudos del caparazón:
Básicamente podemos diferenciar entre tres tipos de escudos distintos:

http://www.infotortuga.com/2012/10/nombres-de-los-escudos-de...

Most turtles have 13 scutes on the top shell. The top shell can come in many shapes, colors, and sizes. The bottom shell also varies in size and color. In some turtles, the bottom shell has one or two hinges that allow it to open and shut. Turtles cannot climb out or be pulled out of their shells. The shell is part of the turtle's skeleton.

https://www.fishandboat.com/Transact/PennsylvaniaLeagueofAng...

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Note added at 14 mins (2020-09-10 22:40:18 GMT)
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https://www.reef.org/sites/default/files/TurtleID.pdf

7) Most turtle shells are covered with hard scutes, also called shields, which protect the shell. These scutes are overlapping pieces of keratin (the same protein substance in your fingernail and the most abundant type of protein on Earth).

https://www.earthrangers.com/top-10/top-ten-facts-about-turt...

Scutes are also called 'shields'.

These marine reptiles are characterized by a large, streamlined shell (carapace), and non-retractable head and flippers. In all species except the leatherback, the body is covered with hard, keratinized plates called “scutes”. The number and arrangement of scutes on the carapace and head are used to identify between the species.

https://www.cabq.gov/culturalservices/biopark/documents/Sea ...

I've raised my confidence level to 4!