SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c8449cf1984e99fd7257977187763496894f1154e0740d52fed66bfc33d2db2f' 
  AND token = 'VgsPREC80uBFyHo7+CvoTxuCLAsdSEV8wB9QWoY3BLo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00154

JSON explain

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