SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f30ed32819099535d933181cea10391326fe33bad2dc73215a21423b688207a9' 
  AND token = '1v9F7wemCYbuP70CA4f8dOUVO5TqQwPebrohxNW4f9Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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