As filed with the Securities and Exchange Commission on June 29, 2000
                                                      Registration No. 333-____

-------------------------------------------------------------------------------

                       SECURITIES AND EXCHANGE COMMISSION

                             Washington, D.C. 20549
                                ----------------
                                    FORM S-8
                          REGISTRATION STATEMENT UNDER
                           THE SECURITIES ACT OF 1933

                            MGC COMMUNICATIONS, INC.
             (Exact name of Registrant as specified in its charter)


              Nevada                                           88-0360042
(State or other jurisdiction of                             (I.R.S. Employer
incorporation or organization)                           Identification Number)
                                175 Sully's Trail
                               Pittsford, NY 14534
                                 (716) 218-6550
          (Address, including zip code, and telephone number, including
             area code, of Registrant's principal executive offices)

                                ----------------

                Primary Network Holdings, Inc. Stock Option Plan

                           (Full titles of the Plans)
                            ------------------------

                              Kent F. Heyman, Esq.
                                175 Sully's Trail
                               Pittsford, NY 14534
                                 (716) 218-6550
       (Name, address, including zip code, and telephone number, including
                        area code, of agent for service)


                                ----------------

                         CALCULATION OF REGISTRATION FEE
<TABLE>
<CAPTION>

-------------------------------------------------------------------------------------------------------------------
  Title of securities        Amount to be        Proposed maximum        Proposed maximum           Amount of
    to be registered          registered        offering price per      aggregate offering       registration fee
                                                     share(2)                  price
-------------------------------------------------------------------------------------------------------------------
      <S>                    <C>                    <C>                   <C>                       <C>
      Common Stock            46,674(1)              $50.3125             $2,348,285.625            $619.95
-------------------------------------------------------------------------------------------------------------------
</TABLE>


----------------------
(1)      Represents an aggregate of 46,674 shares of the common stock, par value
         $.001 per share (the "Common Stock"), of MGC Communications, Inc. (the
         "Registrant"), under the Primary Network Holdings, Inc. Stock Option
         Plan (the "Stock Option Plan").

(2)      Pursuant to Rules 457(c) and 457(h) of the Securities Act of 1933, as
         amended (the "Securities Act"), the offering price and registration fee
         calculations are based on the average of the high and low prices of the
         Common Stock on the NASDAQ Marketing System on June 27, 2000.

<PAGE>

                                EXPLANATORY NOTE

                  Pursuant to an Agreement and Plan of Merger, dated as of April
17, 2000, among the Registrant, Mpower Merger Sub, Inc. (the "Sub") and Primary
Network Holdings, Inc. ("Primary Network"), among other things, (i) the Sub will
be merged with and into Primary Network on June 23, 2000 (the "Effective Time"),
whereupon the separate existence of the Sub will cease and Primary Network will
be the surviving corporation, (ii) Primary Network will become a wholly owned
subsidiary of the Registrant, (iii) each share of common stock, par value $0.001
per share, of Primary Network ("Primary Network Common Stock"), issued and
outstanding immediately prior to the Effective Time was converted into the right
to receive 0.02022 shares of Common Stock, and (iv) at the Effective Time,
shares of Common Stock, rather than shares of Primary Network Common Stock,
became issuable pursuant to the Stock Option Plan.

<PAGE>

                                       2


                                     Part I

              INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS

Item 1.  Plan Information.*

Item 2.  Registrant Information and Employee Plan Annual Information.*




-------
*    Information required by Part I to be contained in the Section 10(a)
     prospectus is omitted from this Registration Statement on Form S-8 (the
     "Registration Statement"), in accordance with Rule 428 under the Securities
     Act, and the "Note" to Part I of Form S-8.

<PAGE>

                                       3


                                    Part II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3.   Incorporation of Documents by Reference.

          The following documents filed by the Registrant with the Securities
and Exchange Commission (the "Commission") are incorporated herein by reference:

          (a)     The Registrant's Annual Report on Form 10-K for the year ended
                  December 31, 1999.

          (b)     The Registrant's Quarterly Report on Form 10-Q for the quarter
                  ended March 31, 2000.

          (c)     The Registrant's Current Reports on Forms 8-K dated March 13,
                  2000, March 27, 2000, April 17, 2000, May 4, 2000 and June 2,
                  2000.

          (d)     The description of the Registrant's Common Stock contained in
                  its Registration Statement on Form 8-A dated April 21, 1998,
                  and in that certain Registration Statement on Form S-3 (No.
                  333-79863) registering shares of the Registrant's Common Stock
                  under the Securities Act, filed with the Commission.

          In addition to the foregoing, all documents subsequently filed by the
Registrant pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Securities
Exchange Act of 1934, as amended (the "Exchange Act"), prior to the filing of a
post-effective amendment indicating that all of the securities offered hereunder
have been sold or which deregisters all securities then remaining unsold, shall
be deemed to be incorporated by reference in this Registration Statement and to
be a part hereof from the date of filing of such documents. Any statement
contained in a document incorporated by reference in this Registration Statement
shall be deemed to be modified or superseded for purposes of this Registration
Statement to the extent that a statement contained herein or in any subsequently
filed document that is also incorporated by reference herein modifies or
supersedes such statement. Any statement so modified or superseded shall not be
deemed, except as so modified or superseded, to constitute a part of this
Registration Statement.

Item 4.   Description of Securities.

          Not applicable.

Item 5.   Interests of Named Experts and Counsel.

          The legality of the Common Stock offered hereby has been passed on for
the Company by Ellis, Funk, Goldberg, Labovitz & Dokson, P.C., Atlanta, Georgia.
Certain shareholders of Ellis, Funk, Goldberg, Labovitz & Dokson, P.C. own
approximately 21,600 shares of Common Stock of the Company.

Item 6.   Indemnification of Directors and Officers.

          The articles of incorporation of the Registrant provide that the
Registrant shall indemnify any director or officer for any liability and legal
expenses, including attorneys' fees, judgments, fines and amounts paid in
settlement actually and reasonably incurred by him arising out of his status or
actions as a director or officer if he acted in good faith and in a manner which
he reasonably believed to be in or not opposed to the best interests of the
Registrant, and had no reasonable cause to believe his conduct was unlawful.

<PAGE>
                                       4

         The by-laws of the Registrant state that, except as otherwise provided
in the Registrant's by-laws, the Registrant shall indemnify any officer or
director in the event he is made a party to a proceeding because he is or was a
director or officer against liability incurred by him in the proceeding if he
acted in good faith and in a manner he believed to be in or not opposed to the
best interests of the Registrant and, in the case of any criminal proceeding, he
had no reasonable cause to believe his conduct was unlawful. The Registrant's
by-laws further state that the Registrant shall not indemnify any officer or
director in connection with a proceeding in which such officer or director was
adjudged liable to the Registrant, unless and only to the extent that the court
in which the proceeding was brought or other court of competent jurisdiction
determines that the officer or director is fairly and reasonably entitled to
indemnity for such expenses as the court deems proper.

          The Registrant's by-laws further provide that the Registrant shall not
indemnify any officer or director unless a separate determination has been made
that indemnification of such officer or director is permissible because he has
met the standard of conduct set forth in the Registrant's by-laws, unless
ordered by a court or advanced pursuant to the section of the Registrant's
by-laws concerning advancement of expenses; provided, however, that regardless
of the result or absence of such determination, to the extent that such officer
or director has been successful on the merits or otherwise in the defense of a
proceeding by or in right of the Registrant to which he was a party, the
Registrant shall indemnify such officer or director against any liability
incurred by him in connection with such proceeding.

          The determination required to be made by the Registrant's by-laws
shall be made, at the election of the board of directors of the Registrant:

          (a)     by the board of directors of the Registrant by majority vote
                  of a quorum consisting of directors not at the time parties to
                  the proceeding;

          (b)     by special independent legal counsel:

                  (1)      selected by the board of directors in the manner
                           prescribed in subparagraph (a) immediately above; or

                  (2)      if a quorum of the board directors cannot be obtained
                           under subparagraph (a) immediately above, selected by
                           a majority vote of the full board of directors (in
                           which selection directors who are parties may
                           participate); or

          (c)     by the shareholders of the Registrant, provided that shares
                  owned by or voted under the control of directors or officers
                  who are at the time parties to the proceeding may not be voted
                  on the determination.

          The Registrant's by-laws further provide that the Registrant shall pay
for or reimburse the reasonable expenses incurred by an officer or director as a
party to a proceeding in advance of final disposition of the proceeding if the
officer or director furnishes to the Registrant a written undertaking to repay
any advances if it is ultimately determined that he is not entitled to any
indemnification under the Registrant's by-laws or otherwise.

          The Registrant's by-laws also provide that the rights of an officer or
director to indemnification set forth in the Registrant's by-laws shall be in
addition to any other rights with respect to indemnification, advancement of
expenses or otherwise that such officer or director may be entitled to under
Nevada law.

<PAGE>
                                       5

          Both the Registrant's articles of incorporation and by-laws provide
that it is the intention of the Registrant to provide the indemnification of
officers and directors to the fullest extent provided by Nevada law.

          With certain limitations, Sections 78.7502(1) and (2) of the Nevada
Revised Statutes permit a corporation to indemnify a director or officer who is
a party or is threatened to be made a party to any threatened, pending or
completed action, suit or proceeding, whether civil, criminal, administrative or
investigative, by reason of the fact that he is or was a director, officer,
employee or agent of the corporation, or is or was serving at the request of the
corporation as a director, officer, employee or agent of another corporation,
partnership, joint venture, trust or other enterprise, against expenses
including attorney fees, judgments, fines and amounts paid in settlement
actually and reasonably incurred by him in connection with the action, suit or
proceeding if he acted in good faith and in a manner which he reasonably
believed to be in or not opposed to the interest of the corporation, and, with
respect to any criminal action or proceeding, had no reasonable cause to believe
his conduct was unlawful.

          The Registrant's articles of incorporation provide that the personal
liability of all directors and officers of the Registrant to any person shall be
eliminated or limited to the maximum extent allowed by Nevada law except that
directors and officers shall be liable for any acts or omissions which involve
intentional misconduct, fraud or a knowing violation of law, or the payment of
dividends in violation of Section 78.300 of the Nevada Revised Statutes.

          As permitted by Section 78.752 of the Nevada Revised Statutes, the
Registrant maintains liability insurance covering directors and officers.

Item 7.   Exemption from Registration Claimed.

          Not applicable.

Item 8.   Exhibits.

          See Exhibit Index.

Item 9.   Undertakings.

          (a)     The undersigned Registrant hereby undertakes:

                  (1)      to file, during any period in which offers or sales
                           are being made, a post-effective amendment to this
                           Registration Statement to include any material
                           information with respect to the plan of distribution
                           not previously disclosed in the Registration
                           Statement or any material change to such information
                           in the Registration Statement;

                  (2)      that, for the purpose of determining any liability
                           under the Securities Act, each such post-effective
                           amendment shall be deemed to be a new registration
                           statement relating to the securities offered therein,
                           and the offering of such securities at that time
                           shall be deemed to be the initial bona fide offering
                           thereof; and

                  (3)      to remove from registration by means of a
                           post-effective amendment any of the securities being
                           registered which remain unsold at the termination of
                           the offering.

<PAGE>
                                       6

                  (b)      The undersigned Registrant hereby further undertakes
                           that, for purposes of determining any liability under
                           the Securities Act, each filing of the Registrant's
                           annual report pursuant to Section 13(a) or 15(d) of
                           the Exchange Act that is incorporated by reference in
                           the Registration Statement shall be deemed to be a
                           new registration statement relating to the securities
                           offered therein, and the offering of such securities
                           at that time shall be deemed to be the initial bona
                           fide offering thereof.

                  (c)      Insofar as indemnification for liabilities arising
                           under the Securities Act may be permitted to
                           directors, officers and controlling persons of the
                           Registrant pursuant to the foregoing provisions, or
                           otherwise, the Registrant has been advised that in
                           the opinion of the Commission such indemnification is
                           against public policy as expressed in the Securities
                           Act and is, therefore, unenforceable. In the event
                           that a claim for indemnification against such
                           liabilities (other than the payment by the Registrant
                           of expenses incurred or paid by a director, officer
                           or controlling person of the Registrant in the
                           successful defense of any action, suit or proceeding)
                           is asserted by such director, officer or controlling
                           person in connection with the securities being
                           registered, the Registrant will, unless in the
                           opinion of its counsel the matter has been settled by
                           controlling precedent, submit to a court of
                           appropriate jurisdiction the question whether such
                           indemnification by it is against public policy as
                           expressed in the Securities Act and will be governed
                           by the final adjudication of such issue.

<PAGE>
                                       7

                                   SIGNATURES

          Pursuant to the requirements of the Securities Act of 1933, the
Registrant has duly caused this Form S-8 Registration Statement to be signed on
its behalf by the undersigned, thereunto duly authorized, in the City of
Pittsford, State of New York on June 29, 2000.

                                  MGC COMMUNICATIONS, INC.




                              By: /s/   Rolla P. Huff
                                  -----------------------------------
                                        Rolla P. Huff
                                        President and Chief Executive Officer




                                POWER OF ATTORNEY

          We, the undersigned directors and executive officers of MGC
COMMUNICATIONS, INC., hereby severally constitute Kent F. Heyman and Mark
Magarian, and each of them singly, our true and lawful attorneys with full power
to them and each of them to sign for us, and in our names in the capacities
indicated below, any and all amendments to this Registration Statement filed
with the Commission, hereby ratifying and confirming our signatures as they may
be signed by our said attorneys to any and all amendments to said Registration
Statement.

          Pursuant to the requirements of the Securities Act of 1933, this Form
S-8 Registration Statement has been signed by the following persons in the
capacities indicated on the 29th day of June, 2000.

<TABLE>
<CAPTION>
Signature                                                     Capacity
---------                                                     --------
<S>                                             <C>
  /s/     Rolla P. Huff                         President and Chief Executive Officer
-----------------------------------------
          Rolla P. Huff




  /s/     Michael R. Daley                      Executive Vice President and Chief Financial Officer
-----------------------------------------
          Michael R. Daley




  /s/     Frank Szabo                           Vice President and Controller
-----------------------------------------
          Frank Szabo




  /s/     Maurice J. Gallagher, Jr.             Chairman of the Board and Director
-----------------------------------------
          Maurice J. Gallagher, Jr.
</TABLE>

<PAGE>
                                       8




-----------------------------------------       Director
          Timothy P. Flynn




  /s/     David Kronfeld                        Director
-----------------------------------------
          David Kronfeld




  /s/     Mark J. Masiello                      Director
-----------------------------------------
          Mark J. Masiello




-----------------------------------------       Director
          Richard W. Miller




  /s/     Thomas Neustaetter                    Director
-----------------------------------------
          Thomas Neustaetter




  /s/      Mark Pelson                          Director
-----------------------------------------
          Mark Pelson

<PAGE>
                                       9


                                  Exhibit Index



Exhibit No.        Description of Document

4.1                Primary Network Holdings, Inc. Stock Option Plan.

5.1                Opinion of Ellis, Funk, Goldberg, Labovitz & Dokson, P.C.

23.1               Consent of Arthur Andersen LLP.

23.2               Consent of Ellis, Funk, Goldberg, Labovitz & Dokson, P.C.
                   (included in Exhibit 5.1).

24.1               Power of Attorney (included on signature page).
[{"type": "S-8", "sequence": "1", "filename": "0001.txt", "description": "FORM S-8", "secsgml_size_bytes": 21610}]
{"company-data": {"conformed-name": "MGC COMMUNICATIONS INC", "cik": "0001047960", "assigned-sic": "4813", "irs-number": "880360042", "state-of-incorporation": "NV", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-40458", "film-number": "665340"}, "business-address": {"street1": "171 SULLYS TRAIL", "street2": "SUITE 202", "city": "PITTSFORD", "state": "NY", "zip": "14534", "phone": "7162186550"}, "mail-address": {"street1": "171 SULLTS TRAIL", "street2": "SUITE 202", "city": "PITTSFORD", "state": "NY", "zip": "14534"}}
As filed with the Securities and Exchange Commission on June 29, 2000
                                                      Registration No. 333-____

-------------------------------------------------------------------------------

                       SECURITIES AND EXCHANGE COMMISSION

                             Washington, D.C. 20549
                                ----------------
                                    FORM S-8
                          REGISTRATION STATEMENT UNDER
                           THE SECURITIES ACT OF 1933

                            MGC COMMUNICATIONS, INC.
             (Exact name of Registrant as specified in its charter)

              Nevada                                           88-0360042
(State or other jurisdiction of                             (I.R.S. Employer
incorporation or organization)                           Identification Number)
                                175 Sully's Trail
                               Pittsford, NY 14534
                                 (716) 218-6550
          (Address, including zip code, and telephone number, including
             area code, of Registrant's principal executive offices)

                                ----------------

                Primary Network Holdings, Inc. Stock Option Plan

                           (Full titles of the Plans)
                            ------------------------

                              Kent F. Heyman, Esq.
                                175 Sully's Trail
                               Pittsford, NY 14534
                                 (716) 218-6550
       (Name, address, including zip code, and telephone number, including
                        area code, of agent for service)

                                ----------------

                         CALCULATION OF REGISTRATION FEE
-------------------------------------------------------------------------------------------------------------------
  Title of securities        Amount to be        Proposed maximum        Proposed maximum           Amount of
    to be registered          registered        offering price per      aggregate offering       registration fee
                                                     share(2)                  price
-------------------------------------------------------------------------------------------------------------------
Common Stock            46,674(1)              $50.3125             $2,348,285.625            $619.95
-------------------------------------------------------------------------------------------------------------------
----------------------
(1)      Represents an aggregate of 46,674 shares of the common stock, par value
         $.001 per share (the "Common Stock"), of MGC Communications, Inc. (the
         "Registrant"), under the Primary Network Holdings, Inc. Stock Option
         Plan (the "Stock Option Plan").

(2)      Pursuant to Rules 457(c) and 457(h) of the Securities Act of 1933, as
         amended (the "Securities Act"), the offering price and registration fee
         calculations are based on the average of the high and low prices of the
         Common Stock on the NASDAQ Marketing System on June 27, 2000.
EXPLANATORY NOTE

                  Pursuant to an Agreement and Plan of Merger, dated as of April
17, 2000, among the Registrant, Mpower Merger Sub, Inc. (the "Sub") and Primary
Network Holdings, Inc. ("Primary Network"), among other things, (i) the Sub will
be merged with and into Primary Network on June 23, 2000 (the "Effective Time"),
whereupon the separate existence of the Sub will cease and Primary Network will
be the surviving corporation, (ii) Primary Network will become a wholly owned
subsidiary of the Registrant, (iii) each share of common stock, par value $0.001
per share, of Primary Network ("Primary Network Common Stock"), issued and
outstanding immediately prior to the Effective Time was converted into the right
to receive 0.02022 shares of Common Stock, and (iv) at the Effective Time,
shares of Common Stock, rather than shares of Primary Network Common Stock,
became issuable pursuant to the Stock Option Plan.
2

                                     Part I

              INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS

Item 1.  Plan Information.*

Item 2.  Registrant Information and Employee Plan Annual Information.*

-------
*    Information required by Part I to be contained in the Section 10(a)
     prospectus is omitted from this Registration Statement on Form S-8 (the
     "Registration Statement"), in accordance with Rule 428 under the Securities
     Act, and the "Note" to Part I of Form S-8.
3

                                    Part II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3.   Incorporation of Documents by Reference.

          The following documents filed by the Registrant with the Securities
and Exchange Commission (the "Commission") are incorporated herein by reference:

          (a)     The Registrant's Annual Report on Form 10-K for the year ended
                  December 31, 1999.

          (b)     The Registrant's Quarterly Report on Form 10-Q for the quarter
                  ended March 31, 2000.

          (c)     The Registrant's Current Reports on Forms 8-K dated March 13,
                  2000, March 27, 2000, April 17, 2000, May 4, 2000 and June 2,
                  2000.

          (d)     The description of the Registrant's Common Stock contained in
                  its Registration Statement on Form 8-A dated April 21, 1998,
                  and in that certain Registration Statement on Form S-3 (No.
                  333-79863) registering shares of the Registrant's Common Stock
                  under the Securities Act, filed with the Commission.

          In addition to the foregoing, all documents subsequently filed by the
Registrant pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Securities
Exchange Act of 1934, as amended (the "Exchange Act"), prior to the filing of a
post-effective amendment indicating that all of the securities offered hereunder
have been sold or which deregisters all securities then remaining unsold, shall
be deemed to be incorporated by reference in this Registration Statement and to
be a part hereof from the date of filing of such documents. Any statement
contained in a document incorporated by reference in this Registration Statement
shall be deemed to be modified or superseded for purposes of this Registration
Statement to the extent that a statement contained herein or in any subsequently
filed document that is also incorporated by reference herein modifies or
supersedes such statement. Any statement so modified or superseded shall not be
deemed, except as so modified or superseded, to constitute a part of this
Registration Statement.

Item 4.   Description of Securities.

          Not applicable.

Item 5.   Interests of Named Experts and Counsel.

          The legality of the Common Stock offered hereby has been passed on for
the Company by Ellis, Funk, Goldberg, Labovitz & Dokson, P.C., Atlanta, Georgia.
Certain shareholders of Ellis, Funk, Goldberg, Labovitz & Dokson, P.C. own
approximately 21,600 shares of Common Stock of the Company.

Item 6.   Indemnification of Directors and Officers.

          The articles of incorporation of the Registrant provide that the
Registrant shall indemnify any director or officer for any liability and legal
expenses, including attorneys' fees, judgments, fines and amounts paid in
settlement actually and reasonably incurred by him arising out of his status or
actions as a director or officer if he acted in good faith and in a manner which
he reasonably believed to be in or not opposed to the best interests of the
Registrant, and had no reasonable cause to believe his conduct was unlawful.
4

         The by-laws of the Registrant state that, except as otherwise provided
in the Registrant's by-laws, the Registrant shall indemnify any officer or
director in the event he is made a party to a proceeding because he is or was a
director or officer against liability incurred by him in the proceeding if he
acted in good faith and in a manner he believed to be in or not opposed to the
best interests of the Registrant and, in the case of any criminal proceeding, he
had no reasonable cause to believe his conduct was unlawful. The Registrant's
by-laws further state that the Registrant shall not indemnify any officer or
director in connection with a proceeding in which such officer or director was
adjudged liable to the Registrant, unless and only to the extent that the court
in which the proceeding was brought or other court of competent jurisdiction
determines that the officer or director is fairly and reasonably entitled to
indemnity for such expenses as the court deems proper.

          The Registrant's by-laws further provide that the Registrant shall not
indemnify any officer or director unless a separate determination has been made
that indemnification of such officer or director is permissible because he has
met the standard of conduct set forth in the Registrant's by-laws, unless
ordered by a court or advanced pursuant to the section of the Registrant's
by-laws concerning advancement of expenses; provided, however, that regardless
of the result or absence of such determination, to the extent that such officer
or director has been successful on the merits or otherwise in the defense of a
proceeding by or in right of the Registrant to which he was a party, the
Registrant shall indemnify such officer or director against any liability
incurred by him in connection with such proceeding.

          The determination required to be made by the Registrant's by-laws
shall be made, at the election of the board of directors of the Registrant:

          (a)     by the board of directors of the Registrant by majority vote
                  of a quorum consisting of directors not at the time parties to
                  the proceeding;

          (b)     by special independent legal counsel:

                  (1)      selected by the board of directors in the manner
                           prescribed in subparagraph (a) immediately above; or

                  (2)      if a quorum of the board directors cannot be obtained
                           under subparagraph (a) immediately above, selected by
                           a majority vote of the full board of directors (in
                           which selection directors who are parties may
                           participate); or

          (c)     by the shareholders of the Registrant, provided that shares
                  owned by or voted under the control of directors or officers
                  who are at the time parties to the proceeding may not be voted
                  on the determination.

          The Registrant's by-laws further provide that the Registrant shall pay
for or reimburse the reasonable expenses incurred by an officer or director as a
party to a proceeding in advance of final disposition of the proceeding if the
officer or director furnishes to the Registrant a written undertaking to repay
any advances if it is ultimately determined that he is not entitled to any
indemnification under the Registrant's by-laws or otherwise.

          The Registrant's by-laws also provide that the rights of an officer or
director to indemnification set forth in the Registrant's by-laws shall be in
addition to any other rights with respect to indemnification, advancement of
expenses or otherwise that such officer or director may be entitled to under
Nevada law.
5

          Both the Registrant's articles of incorporation and by-laws provide
that it is the intention of the Registrant to provide the indemnification of
officers and directors to the fullest extent provided by Nevada law.

          With certain limitations, Sections 78.7502(1) and (2) of the Nevada
Revised Statutes permit a corporation to indemnify a director or officer who is
a party or is threatened to be made a party to any threatened, pending or
completed action, suit or proceeding, whether civil, criminal, administrative or
investigative, by reason of the fact that he is or was a director, officer,
employee or agent of the corporation, or is or was serving at the request of the
corporation as a director, officer, employee or agent of another corporation,
partnership, joint venture, trust or other enterprise, against expenses
including attorney fees, judgments, fines and amounts paid in settlement
actually and reasonably incurred by him in connection with the action, suit or
proceeding if he acted in good faith and in a manner which he reasonably
believed to be in or not opposed to the interest of the corporation, and, with
respect to any criminal action or proceeding, had no reasonable cause to believe
his conduct was unlawful.

          The Registrant's articles of incorporation provide that the personal
liability of all directors and officers of the Registrant to any person shall be
eliminated or limited to the maximum extent allowed by Nevada law except that
directors and officers shall be liable for any acts or omissions which involve
intentional misconduct, fraud or a knowing violation of law, or the payment of
dividends in violation of Section 78.300 of the Nevada Revised Statutes.

          As permitted by Section 78.752 of the Nevada Revised Statutes, the
Registrant maintains liability insurance covering directors and officers.

Item 7.   Exemption from Registration Claimed.

          Not applicable.

Item 8.   Exhibits.

          See Exhibit Index.

Item 9.   Undertakings.

          (a)     The undersigned Registrant hereby undertakes:

                  (1)      to file, during any period in which offers or sales
                           are being made, a post-effective amendment to this
                           Registration Statement to include any material
                           information with respect to the plan of distribution
                           not previously disclosed in the Registration
                           Statement or any material change to such information
                           in the Registration Statement;

                  (2)      that, for the purpose of determining any liability
                           under the Securities Act, each such post-effective
                           amendment shall be deemed to be a new registration
                           statement relating to the securities offered therein,
                           and the offering of such securities at that time
                           shall be deemed to be the initial bona fide offering
                           thereof; and

                  (3)      to remove from registration by means of a
                           post-effective amendment any of the securities being
                           registered which remain unsold at the termination of
                           the offering.
6

                  (b)      The undersigned Registrant hereby further undertakes
                           that, for purposes of determining any liability under
                           the Securities Act, each filing of the Registrant's
                           annual report pursuant to Section 13(a) or 15(d) of
                           the Exchange Act that is incorporated by reference in
                           the Registration Statement shall be deemed to be a
                           new registration statement relating to the securities
                           offered therein, and the offering of such securities
                           at that time shall be deemed to be the initial bona
                           fide offering thereof.

                  (c)      Insofar as indemnification for liabilities arising
                           under the Securities Act may be permitted to
                           directors, officers and controlling persons of the
                           Registrant pursuant to the foregoing provisions, or
                           otherwise, the Registrant has been advised that in
                           the opinion of the Commission such indemnification is
                           against public policy as expressed in the Securities
                           Act and is, therefore, unenforceable. In the event
                           that a claim for indemnification against such
                           liabilities (other than the payment by the Registrant
                           of expenses incurred or paid by a director, officer
                           or controlling person of the Registrant in the
                           successful defense of any action, suit or proceeding)
                           is asserted by such director, officer or controlling
                           person in connection with the securities being
                           registered, the Registrant will, unless in the
                           opinion of its counsel the matter has been settled by
                           controlling precedent, submit to a court of
                           appropriate jurisdiction the question whether such
                           indemnification by it is against public policy as
                           expressed in the Securities Act and will be governed
                           by the final adjudication of such issue.
7

                                   SIGNATURES

          Pursuant to the requirements of the Securities Act of 1933, the
Registrant has duly caused this Form S-8 Registration Statement to be signed on
its behalf by the undersigned, thereunto duly authorized, in the City of
Pittsford, State of New York on June 29, 2000.

                                  MGC COMMUNICATIONS, INC.

                              By: /s/   Rolla P. Huff
                                  -----------------------------------
                                        Rolla P. Huff
                                        President and Chief Executive Officer

                                POWER OF ATTORNEY

          We, the undersigned directors and executive officers of MGC
COMMUNICATIONS, INC., hereby severally constitute Kent F. Heyman and Mark
Magarian, and each of them singly, our true and lawful attorneys with full power
to them and each of them to sign for us, and in our names in the capacities
indicated below, any and all amendments to this Registration Statement filed
with the Commission, hereby ratifying and confirming our signatures as they may
be signed by our said attorneys to any and all amendments to said Registration
Statement.

          Pursuant to the requirements of the Securities Act of 1933, this Form
S-8 Registration Statement has been signed by the following persons in the
capacities indicated on the 29th day of June, 2000.
Signature                                                     Capacity
---------                                                     --------
/s/     Rolla P. Huff                         President and Chief Executive Officer
-----------------------------------------
          Rolla P. Huff

  /s/     Michael R. Daley                      Executive Vice President and Chief Financial Officer
-----------------------------------------
          Michael R. Daley

  /s/     Frank Szabo                           Vice President and Controller
-----------------------------------------
          Frank Szabo

  /s/     Maurice J. Gallagher, Jr.             Chairman of the Board and Director
-----------------------------------------
          Maurice J. Gallagher, Jr.
8

-----------------------------------------       Director
          Timothy P. Flynn

  /s/     David Kronfeld                        Director
-----------------------------------------
          David Kronfeld

  /s/     Mark J. Masiello                      Director
-----------------------------------------
          Mark J. Masiello

-----------------------------------------       Director
          Richard W. Miller

  /s/     Thomas Neustaetter                    Director
-----------------------------------------
          Thomas Neustaetter

  /s/      Mark Pelson                          Director
-----------------------------------------
          Mark Pelson
9

                                  Exhibit Index

Exhibit No.        Description of Document

4.1                Primary Network Holdings, Inc. Stock Option Plan.

5.1                Opinion of Ellis, Funk, Goldberg, Labovitz & Dokson, P.C.

23.1               Consent of Arthur Andersen LLP.

23.2               Consent of Ellis, Funk, Goldberg, Labovitz & Dokson, P.C.
                   (included in Exhibit 5.1).

24.1               Power of Attorney (included on signature page).