SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8e9fb2cee8b766708e272287b010cd9f52c22d516dadbf9804bb4a08f92e09c0' 
  AND token = 'xHQeFrdPPwR/Vlkh8jpyjr68OwYKqakTNcFWbhgAfIo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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