SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c6dd606d72c46283e77ef611628c5c9b991bb941a6918f1be7105c033df5e219' 
  AND token = 'KVLo1cwf9DMwyyf17buJYnbUumKhVw0eQWl3K4zenBs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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