SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1ea1321519082db81b6785d9d7942cf6451f6047e47ccdd310b67293594a7be3' 
  AND token = 'pFGjpWfh00frnnakcBymfEZjmeibjh/xc72Uf2rHV0M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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