SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '128cc3415d61f2d2e42ddd6626213ab22081a39999c1b9cda484ac9078d138bf' 
  AND token = 'OTvWbXDWXidkUIU3hd+/K3eaBgTlybodzc4YCgJSXic=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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