SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd93d15eab3f40f790164495b47e0ee0106cc00c113fefe2895b4b31f97f86a73' 
  AND token = 'JzGNOYAOsTVYJ7fIwGzI8QDSiVnvxbqxFu5SZwh+Rdk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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