SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '59cf362bc766ed693a0ab2b06a3dc0ccc07758b8bf0a67f3ce81fc847832a758' 
  AND token = 'k7M7glwkPwCGaSEUl2lxRaMoBBOxLmaAhe8jID61Rww=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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