SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ae3858efa681d8e72499e35d765856f473b6e138674498d647f27b79e5de621a' 
  AND token = 'Rp3kzFPcSqlk5MJDG8ZTjcVfpCK2KpWtpNHI0h+Uw8k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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