SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e2f5f6ca8b612c4d6b2c05bdaa7799a43009ac18fde15ae9af0aa58e83634de2' 
  AND token = 'U1avTFONn7TKnHMcvRrlM6qNJDCjKjGTtegXESeVIzs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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