SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4d855035cc9de0db0eb927c68553df58e98cc8fcad8770e585281055a988f72c' 
  AND token = '0FsBUQPToSVPzBLlfqCJAbfkNyd0aGSjFWx5mRsDSjs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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