SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4fd1c492d4b3411615cd2234d60cb0c599abb5385f99a885ec2ce9c36fb15a91' 
  AND token = 'nIzGIGVBQqbgbfIPZLhGDjhOGBu+j8+yURV2nJUg6ZY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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