SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cc85af45edbff22e1980207871c574b47366cf3597a59e212d883c1ca1b3401e' 
  AND token = 'H2s/hOo0xNeI6CsVzLPZM5yV5k+9YvQt5FyUesJSSUI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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