SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '485fa3b08ea47b5b5a6a10ba93e835cba2f349a759a6a0066e2a4debf08e2658' 
  AND token = '6sYmGINTgHVztlFzX8DoFul3zV4vpEyQ9zovKrJ/SPY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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