SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f016c1c89668cc83907529c74df8135b60a0d7955264cc1ba3b5af333ffccb62' 
  AND token = 'WEYjSi9XTIxCs9LgJxHphMzlgmHKtie+cMa/juY+LC0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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