SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '98d85456fa9865fea659b44c72b6d09d13162f8f3eae689573b2b9fdf5400cac' 
  AND token = 'wj7PwnSPJXqJz7kcyQcMtsKYvPpe2ArYJibfpQTwVIs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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