SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'de1bb61856e1e7c89d528ce10f7813d991151fb96efed37271ede84ad4ed5d75' 
  AND token = 'evyoIgE7WyY1ywYJ8lUhPsBiG73yXDgDgKN89YsK850=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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