SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '328c8c5bcd849000918aefd90be3fadae9eb60b363e79ad98a8751d6fbf80a6f' 
  AND token = 'Tybe4nlFLeR+l9zJhFKXTioWGWCZc5hz6hb/69krzGs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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