SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '172f4e692da8e173c9b6492736fdcf5aaf2a19f4905a5f0f9d43fd9f80ba06e4' 
  AND token = 'uH8I2RDFwVhnoMxnm4OzTL+dadWXA9Tm/SvHmLKhEGg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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