SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1fd312cfc9b7ef4cb0d2bdf684dbcff4ecf16b212d346a62d9984036305cb39c' 
  AND token = 'V6iXEc2w49355QqjG4XuWyOtUfUup3zgRtAogmYD5uk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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