SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'de792f0eb3845ab43ce2bedbf973553d672689a37f2cb9f70497e115d9579499' 
  AND token = 'Jsu1gArgwC+DV/b7bawhXF3Hn/Gp2APvAVJMxMvySgg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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