Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f9cb548fc8d7a4ec713eedc7fc5dd1fec9aefa69534f1ac55d1966b2c5f7d97c' 
  AND token = 'fsgIa4Up+wHgnPKkf9fJCTYXhR6wuUhgpyYS0u4E2v0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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