SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '02c3afd0be990a3dd4d36b4105606888a64df0c567b3fbc6398862ee765c7279' 
  AND token = 'w/FLjiDQOKcrbZbOydomhG4grUlJgK5mJDhZC7KrN6o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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