SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a27460c6e03985f709d5c086657233ebc7610eab1775eb78a99f5dff9496d707' 
  AND token = 'rWiOsCg+mgv1+qY8k/TKKVQJDHe/8elVc/+4hCvtKcs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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