SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '31e54a50f3f6c8a2320c660143bf49392fd271b5af118d3bcbc3399cdb40e1ed' 
  AND token = 'KT7BzT3VOfOaFxHOrKdpOvmiYQ8wB286qFcUSQ5xBnw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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