SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ec863eb917adb2e8c086a0d7862604e16d8dc6b668166c75319cd476e1b91345' 
  AND token = 'HsgivhwxANIUXBvPN4UCrspexolAe3FG4Mkh4WRckHs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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