SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'fa13cf48318d968cdb13034cb3231fb604b4a6f6bd52616397597d1b2e536bcf' 
  AND token = 'ttWM4ej4N2/L5YgWF+pdi1pS/KSE4SS6lIWS9I1xX5Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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