SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2ca711fd3cfc3294de6a5e8c16779aefdbcbd3defef448ddeed09949b519834e' 
  AND token = 'swUvmI4cUXwCCC7JqAOI/lMh+0c89Dp3fGz6/V4Segg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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