SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '73363ce2550bbb1cf14282512626a21448dd71248d2c3120e43fceb929ce41cc' 
  AND token = 'Tc4khcWs/FRnoVyf5UqhA1GGew/9mBhGf5qIcwi1yUI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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