SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0aacf1c8d2ec17ccd623ae81cbc21a3b6c4ef92bc9c2ef1da5ea0114040ac2c4' 
  AND token = '2k57AxmXEFp0StWZ8vPUYDzos8au1QDkxDgEkb1itYM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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