SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'dc545734c96b630a59166ff02701be598b2b27ddfedc1996f4c015016fd2bf23' 
  AND token = 'Y17ZvprMDBNWdhBvhLK3pZtsqeYDpTXUergUvKr/q6E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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