SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0e3f0c7bdb2aae9c6a6ddbba92c8d19ceb56f2ff409b7165b743ac4d87174ee8' 
  AND token = 'YzYoX9lgBUTqjg8CiXom/X+CtWUKWL2/0UtaScQGgo4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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