SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a63d61c03eb06ff3f8800df410002ae05b3048bcb8a6d6cddb3ed3285aec2412' 
  AND token = 'jVsnpUmjjizqZ5zbIlDK8RgpkwQwQYUt6BUCAOGqM+s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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