Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6e89ba390ce3491c1c14768632f8fb63f75e1ba58a934c34101a3ff6e2eff9a6' 
  AND token = 'CAXYPo3/ahwGDcrUYqihzRkBY+hnY2eLCeCQzGRIAnE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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