SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '806a7badaa8fb14e0f22d748f774e76373ab77db15b97dcf9a27e7b3fad1f6f2' 
  AND token = 'Bin+J9qzVkZagDlJIIxX12YMIMgbOPSMxBquBjBGpLo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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