SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '23ad0bd1c50d799ce48e54c9f823ed2a17767415f2fc2c6a4ded706abdf8b50e' 
  AND token = 'kijQHHpDIxXGJY51sajRw0FbTZR0K/SlUacq2BthqaM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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