SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bb3765aa8eb7860c38d33ae097f969ea3f091eee0a85c13a965095f860e5a17c' 
  AND token = 'AEJUcmfCI2ViQQu+krMHuz2bfUV5EShU7VjW14QDM9E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}