SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f69584d6bbd2939edb23434b9852924bcf41e82a58121d47639dcd99018101f2' 
  AND token = 'OyGACCltjZqce1iKBEYwtEiL6vJ3CkOQEKLNatyfYYw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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