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Description
When taking out of context, stegosaurs are easily one of the weirdest dinosaurs ever. Very few people stop to think on how weird stegosaurs really are (I feel bad for those people). Stegosaurs, according to the fossil record, lived from the Middle Jurassic to the Early Cretaceous, though stegosaurs probably originated in the Early Jurassic, somewhere. They were herbivores and are easily distinguished by their small heads, longish necks, and a row of weird plates and spikes running over its back. They are known from almost every continent, except Australia and Antarctica, ranging from a meter long to almost ten meters long. For the time being, there are two recognized families of stegosaurs: Huayangosauridae and Stegosauridae. However, Isaberrysaura, if its an actual stegosaur, would easily be positioned in a basal position within the clade, and would, as a result, be outside of either of these two families. Gigantspinosaurus has also been placed outside either of the two, though it is traditionally placed as a basal stegosaurid.

In the image, we see three emblematic stegosaurids from the Late Jurassic. From right to left:

1. Kentrosaurus aethiopicus is a basal stegosaurid, that lived 152 million years ago, in the Tendaguru Formation of Tanzania. It was relatively small, with 4.5 meters in length. It is characterized for a physique consistent with basal forms of stegosaurs, including the presence of a long spike in each shoulder. Its plates are also smaller and its tail is filled with spikes.
2. Miragaia longicollum is a large stegosaurid, that lived 150 million years ago, in the Lourinhã Formation of Portugal (my country). It may have possibly lived in the Morrison Formation, in the United States, but it depends if Alcovasaurus really is a synonym of Miragaia. Miragaia is unique for having a very big ass neck, one of the longest, if not the longest necks of any ornithischian, with 17 vertebrae (it surprisingly isn't the ornithischian with the largest amount of neck vertebrae, Olorotitan, iirc, breaks that record with 18 neck vertebrae). Miragaia also had enormously tall plates and spikes. It literally freaks me out.
3. Stegosaurus stenops is easily the most famous stegosaurid ever. It lived in the Morrison Formation, in the United States of America, some 155 to 145 million years ago. There's also Stegosaurus remains attributed to the Lourinhã Formation, but I don't have the knowledge to speak about them too much. Similarly to Miragaia and to other derived stegosaurids, Stegosaurus lacked shoulder spikes. Stegosaurus was easily one of the largest stegosaurids in existence, and, in a sense, it was rather unique. Its plates were enormous and wide and displayed very assymetrically across its back, with the tail ending in a thagomizer with just two pairs of enormous spikes. We have direct skin impressions from Stegosaurus displaying, expectedly, a scaly skin, useful for protection against predator attacks.

Description
When taking out of context, stegosaurs are easily one of the weirdest dinosaurs ever. Very few people stop to think on how weird stegosaurs really are (I feel bad for those people). Stegosaurs, according to the fossil record, lived from the Middle Jurassic to the Early Cretaceous, though stegosaurs probably originated in the Early Jurassic, somewhere. They were herbivores and are easily distinguished by their small heads, longish necks, and a row of weird plates and spikes running over its back. They are known from almost every continent, except Australia and Antarctica, ranging from a meter long to almost ten meters long. For the time being, there are two recognized families of stegosaurs: Huayangosauridae and Stegosauridae. However, Isaberrysaura, if its an actual stegosaur, would easily be positioned in a basal position within the clade, and would, as a result, be outside of either of these two families. Gigantspinosaurus has also been placed outside either of the two, though it is traditionally placed as a basal stegosaurid.

In the image, we see three emblematic stegosaurids from the Late Jurassic. From right to left:

1. Kentrosaurus aethiopicus is a basal stegosaurid, that lived 152 million years ago, in the Tendaguru Formation of Tanzania. It was relatively small, with 4.5 meters in length. It is characterized for a physique consistent with basal forms of stegosaurs, including the presence of a long spike in each shoulder. Its plates are also smaller and its tail is filled with spikes.
2. Miragaia longicollum is a large stegosaurid, that lived 150 million years ago, in the Lourinhã Formation of Portugal (my country). It may have possibly lived in the Morrison Formation, in the United States, but it depends if Alcovasaurus really is a synonym of Miragaia. Miragaia is unique for having a very big ass neck, one of the longest, if not the longest necks of any ornithischian, with 17 vertebrae (it surprisingly isn't the ornithischian with the largest amount of neck vertebrae, Olorotitan, iirc, breaks that record with 18 neck vertebrae). Miragaia also had enormously tall plates and spikes. It literally freaks me out.
3. Stegosaurus stenops is easily the most famous stegosaurid ever. It lived in the Morrison Formation, in the United States of America, some 155 to 145 million years ago. There's also Stegosaurus remains attributed to the Lourinhã Formation, but I don't have the knowledge to speak about them too much. Similarly to Miragaia and to other derived stegosaurids, Stegosaurus lacked shoulder spikes. Stegosaurus was easily one of the largest stegosaurids in existence, and, in a sense, it was rather unique. Its plates were enormous and wide and displayed very assymetrically across its back, with the tail ending in a thagomizer with just two pairs of enormous spikes. We have direct skin impressions from Stegosaurus displaying, expectedly, a scaly skin, useful for protection against predator attacks.