On Aquatic Carnivorous Colcoptera or Dytiscidce. 461 



In this species the tarsi of the male are distinctly broader than they are in the 

 female, the species is extremely similar to Hyphydrus pubescens, (No. 568) but is 

 rather more coarsely punctured above, has the antennoe rather more slender, and 

 the third joint of the tarsi not so small. 



North Europe; (Sweden, Finland, Germany). Russian North America. Ascends to 6S^ 20' accord- 

 ing to Sahlberg. 383. 



568. Hyphydrus pubescens, Gyll., Hydroporua puhescens, M.C. — Ovalis, sat con- 

 vexus, minus nitidus, crebrius pubescens, fequaliter, subtiliter fere dense punctatus, 

 niger, pedibus obscure rufis, antennis fuscis basi rufo, ejytris fusco-brunneis, humeris 

 spepe dilutioribus ; coxis poster ioribus sat crebre, fortiter punctatis, abdomine 

 segraento ultimo argute profundeque punctato ; tarsis anterioribus articulo tertio 

 parvo. Long. 31, lat. \l m.m. 



This is a variable species in size and colour; in the more southern part of its area 

 it has frequently the elytra broadly pale at the shoulders. 



It has been thought that this species is the Dytiscus melanocephalus, Marsh. 

 (Hydroporus melanocephalus, Steph.), but as the descriptions leave this quite doubt- 

 ful. I have not thought it advisable to disturb the generally accepted decision which 

 considers Gyllenhall the first describer of the species. It has also been stated that 

 the species intended by Gyllenhall under the name H. pubescens was not this but 

 Hydroporus discretus, Fairm. (No. 564) ; Gyllenhall's description however applies 

 better to the present species than to any other, and there is therefore no sufficient 

 ground for changing the name. 



Eui-ope ; one of the most abundant of the European Dytiscidre : Algeria, Northern Persia ; ascends in 

 Finland to 67°, (Sahlberg) ; Germany, Britain, France, Corsica, Sardinia, Spain, Italy, Greece. 382. 



569. Hydroporus llturatus, BruUe, M.C. — Ovalis, sat convexus, minus elongatus, 

 sat nitidus, tenuiter baud dense pubescens, subtiliter sat crebre punctatus, niger, 

 pedibus antennisque testaceis, his apicem versus fuscis, elytris fuscis, vel fusco- 

 testaceis, basi lateribusque plus minusve late et irregulariter testaceis ; coxis 

 posterioribus sat crebre et fortiter punctatis ; abdomine segmento ultimo indistincte 

 punctato. Long. 31, lat. 2 m.m. 



This is a very variable species in colour, and even in sculpture and pubescence, 

 and its dark varieties approach very closely to Hyphydrus pubescens, but the 

 present insect has the last segment of the hind body always much more indis- 

 tinctly punctured ; the sexes are very difficult to distinguish. 



Bedel assigns to this species the trivial name of tessellatus Drapiez. 



Europe ; Northern Africa ; Persia ; Arabia ; (Scotland, England, France, Corsica, Spain, Cyprus, 

 Sinai, Northern Persia, .Jeddah). 381. 



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