SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '19953987f4037b6b53e3d8876ae5b7c3069775655d9ce7aff65be3977071b6ff' 
  AND token = 'KXTOoKwXDY7AOozIRgKxJYlHmNqnPizhCOuNYV+2h58=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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