Taxonomic purgatory: Sorting out the wasp genus Myzinum Latreille in North America (Hymenoptera, Tiphiidae, Myzininae)
Author
Kimsey, Lynn S.
text
Zootaxa
2009
2224
30
50
journal article
10.5281/zenodo.190193
71dc1d04-e694-4c9b-bc7c-ab528b6540ed
1175-5326
190193
Myzinum obscurum
(Fabricius)
Fig. 5, 21; Map 7
Tiphia obscura
Fabricius 1805
:233
.
Holotype
female; “
Carolina
” (COPENHAGEN).
Plesia nigripes
(Guérin Méneville) 1837:577
.
Holotype
male; no locality given (PARIS). This species was listed by
Krombein (1951)
as a synonym, but the species was moved into the genus
Poecilotiphia
by
Gorbatovsky (1981)
.
Plesia fuliginosa
Lepeletier 1848:581
.
Holotype
male; “Pensylvanie” (PARIS, lost?). Synonymized by
Krombein (1938)
.
Elis berlyi
Brimley 1927
:238
.
Holotype
female;
USA
: South
Carolina, Charleston
(WASHINGTON).
New synonymy
.
Male
.―Body length
20 mm
. Head: hypostome forming right angle in profile; frons punctures small, contiguous, becoming larger towards midocellus; ocellocular distance 1.3x interocellar distance; mandible with small subsidiary tooth; flagellomere I length 1.7x breadth; flagellomere XI length 2.3x breadth. Thorax: mesopleuron with faint omaulus, punctures subcontiguous; propodeum transversely rugosopunctate; fore and hindcoxa unmodified; midcoxa inner margin angulate or dentate. Metasoma: tergum VII flat, smooth apicomedially. Genital capsule (
Fig. 21
): paramere ventral lobe
3x
as broad as long, with five spines extending along apical one-fifth, dorsal lobe marginal setae fewer than six, about three-fourths as long as volsella; volsella parallel-sided, flattened ovoid in cross-section, rounded apically, setose apically, four-fifths as long as paramere ventral lobe; aedeagus apical bulb 1.5x as broad as shaft below. Color: black, with yellow markings;; clypeus yellow; inner eye margin with yellow band along inner margin; antennal lobe with yellow spot; pronotum with broad anterior and posterior yellow bands; mesopleuron with large anterior and smaller posterior yellow spots; scutum, scutellum and metanotum with medial yellow spots; tegula yellow; coxae, femora and tibiae with yellow band or spot; tarsi yellow; propodeum with large yellow lateral spot; metasomal terga I–VI with narrow transverse posterior yellow band, sterna II–VI with elongate posterolateral yellow spot; wing membrane untinted. Ve s t i t u r e.―silvery.
Female
.―Body length
15–22 mm
. Head: frons punctures contiguous from near antennal lobes to midocellus; ocellocular distance 2.2x interocellar distance; vertex punctures 2–4 PD apart; hypostomal angle forming right angle in lateral view; flagellomere I length 0.9x breadth. Thorax: pronotum dorsal surface with contiguous, somewhat striatiform punctures without tiny interpunctures; propodeum laterally densely transversely ridged, posterior surface with fine ridges radiating dorsally and laterally from petiole; foretarsal rake with 7 spines. Color: black, with yellow markings, with brown on antenna, mandible, legs and metasoma; head with yellow band on inner and posterior eye margins; antennal lobe yellow; pronotum with anterolateral yellow spot; mesopleuron with anterior yellow spot; tegula with yellowish margin; metanotum yellow medially; propodeum with small sublateral yellow spot; metasomal terga I–V with lateral yellow spot, sternum II sometimes with small basolateral yellow spot; forewing membrane brown-tinted, somewhat darker along costal margin. Vestiture: silvery.
Distribution
(Map 7).―Eastern
USA
:
Delaware
: Newcastle Co.;
Florida
: Alachua, Collier, Levy, Santa Rosa Counties;
Georgia
: De Kalb, Richmond Counties;
Illinois
: Scotts, Williamson Counties;
Kansas
: Pattawatomi, Riley Counties;
Kentucky
: Beckenridge, Edmonson Counties;
Maryland
: Montgomery Co.;
Mississippi
: Lafayette Co.;
Missouri
: Boone, Henry, Lincoln, Warrenton Counties; Henry, Lincoln Counties;
New
Jersey
: Burlington Co.;
North
Carolina
: Buncombe, Moore, Watauga Counties;
Ohio
: Clermont Co.;
Oklahoma
: Atoka Co.;
South
Carolina
: Charleston Co.;
Texas
:
Cameron
, Frio, Tyler Counties;
Virginia
: Fairfax, Rockbridge, Williamsburg, York Counties;
Washington, D.C
.
63 females
and
4 males
were studied.
Discussion
.―Diagnostic features for this species include the lobate male midcoxa, features of the male genitalia, the dark coloration, and the large, somewhat striatiform punctures on the female pronotum. The male paramere dorsal lobe is nearly half the width of the paramere in side view, with only five apical spines and the volsella is ovoid in cross-section and appears broadest medially.
Myzinum obscurum
occurs in the eastern
U.S.
from Illinois and Maryland south to eastern Texas and Florida.
Myzinum beryli
Brimley
is here synonymized under
obscurum
. Comparison of the
type
females of
beryli
and
obscurum
revealed that the only distinction between the two was the extent of tiny interpunctures on the pronotum. Otherwise the
types
shared the same dark coloration of the wings and body, sculpturing of the propodeum, ocellocular distance and dimensions of the flagellomeres. All of the males associated with
beryli
by Brimley and Krombein actually share features typical of male
obscurum
including the dentate midcoxa.
No justification could be found for the two
beryli
subspecies,
parksi
and
patei
, described by Krombein. Examination of his
type
material revealed the two subspecies to be structurally identical with
carolinianum
, mostly distinguished in his paper by differences in coloration and minor variations in the shape of the paramere. Modifications of the male genitalia of the two subspecies are the same as variation observed in
carolinianum
. Finally the subspecies and
carolinanum
occur in the same regions.