SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ee3a1927698053d0166bb6161e1ea069c810cf84a76c6f4a243b1ced7630481c' 
  AND token = '9Gdg6BYfHQFMPJivQUbFn2In9fJ8wB9R7YfDP6pN9GM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}