SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '43415e07d7da5cf10b90501636aba61f674cbed015ec8272d3de7ff68e0e5f0a' 
  AND token = 'LPZBQu8xWhzNHRtIhglJhotTs9VpaqzFefJ/gkGmnpY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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