SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd2b503ff74be635898df19e8f0392348fb94b8e749bbe2cadf695388507dfa09' 
  AND token = 'oY6ubumeuRlrHrncIh/pYWAsgjo0z4oJTqsyyjEAnqI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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