SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b6ce491e6d715947d45372ef9be1a5f8d0779f369b1c586f971132a92d24a8f1' 
  AND token = 'ddYzfSqlxwpIKW+Ryurhjo8SHTOx6ZrP6r0vUaskADM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00057

JSON explain

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