SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b00ec2f42a4530edea00bab13d0733473df06a9cbf4d65ef9a08bd9c23f793d2' 
  AND token = 'auMEKpQlWveltQWpmX2KhbfKLmYr6XWE6S8EJVy7hT0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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