SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aaa2a2597cdc9465c4a4b55635beb37ab5a6c6c82514e549ce949e9b70bedafe' 
  AND token = 'T9hYSzeMEO3FxrzxFsETj7ZDvzKnqVObIgcCipLqK2Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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