SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cb9e4a8d1bf0a5d9adc2a258b8bef2f63dac24b231847d4473d8a96538583e7d' 
  AND token = 'q3PF8fRyyUxStRoSYdUkMmmejurfvcGOcOtA44cVaNs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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