SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f3be1f55157b53416b4b935fcc52a3c5fd074d665796a16c66e335c2fede8bb0' 
  AND token = 'fDD8hukI9JlDjnbhF3nuS9B9sau1MmUtfIFiytoYkzg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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