SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '74be53fbb7eceb48ac31cd003c238e95889a6bbc53307ac6a81841155c5ff232' 
  AND token = 'ZOXlI7OamzHdnCeWH03w3727ILyutMzXGZ6bYewsGv4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}