Yes, they are actual stats...they show up as named in sys.stats. I thought it was weird for them to be there without a corresponding index too.

Table:

ABCTable

Indexes:

IX_ABCTable

IX_ABCTable_1

Statistics:

_dta_index_ABCTable_7_745806881__K2

_dta_index_ABCTable_7_745806881__K2_5

_dta_index_ABCTable_7_745806881__K2_K1

_dta_index_ABCTable_7_745806881__K5

_dta_index_ABCTable_7_745806881__K5_K2

_dta_index_ABCTable_c_7_745806881__K1_K2

_dta_index_ABCTable_c_7_745806881__K10

_dta_index_ABCTable_c_7_745806881__K2

_dta_stat_745806881_2_1

_dta_stat_745806881_5_2

_WA_Sys_00000003_2C741C21

_WA_Sys_EmailID_2C741C21

_WA_Sys_PK_2C741C21

_WA_Sys_TransactionID_2C741C21

IX_ABCTable

IX_ABCTable_1