SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4ed5c759350c8c4fc0e55b6f33525d8e528c7558b67d0117e6e001011a520740' 
  AND token = 'qHilgvVhVfID8oUOGYBAouCnyETt9oGugEJYESyXAu4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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