SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9382ce701cd1b5b551c2904a2ec93b5837d2fe932c69da3f891d7429bd7f7aea' 
  AND token = '8YGoZtNLQFS/JX4dXhlDLGVUft+BIL+ouXcP0Zyk6aI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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