SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5baf2b021c57265a3c64ec91e94e8083b9b85398fdfdb62428aacfb141839028' 
  AND token = 'EsxkY97ja/i9hjRXxU+pNIjrUu01tduFITQ06QV5iKI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}