SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5bd80742f2af6b8ce1a8c578ff9cf16d6eee8b4df8441967d869fe98fae83f49' 
  AND token = 'WADkMdBWCuKkcJH3GmUFCWmf1/m1A5zkECpPylqq/GA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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