SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fa9ffbbbc536f7ad28c6c59b2b9183c8f2b5e066d19d6f7adfb81cd40e763a12' 
  AND token = 'IwlOV6XjDP/uHxPU5rv/qKfb8TSzNEybkXVFYDPmu1o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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