SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a8718ea6dc48a01327fc9c1335d7857a559173005ec4020c96f56d629f47c813' 
  AND token = 'VIq44NdePZYo9gJ8ElP381/RzAar3POCIm8fVlW+FX0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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