SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7f1d6700ec1d47a47fa7269da99a8243951f20ee969f1e9a0498425f49f8e5b9' 
  AND token = '6wlQaNUBhCpOjY793ZqPyrKvoQjnTu/pxh4Mku2cHSE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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