SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bda240569f7f63044a789f47245580b160047d27f704046dfd5f589329823561' 
  AND token = 'p+87mbaVpqEpNJR7WL/Yf0SSqjv2I42jTmvlEGwZWbM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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