SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cc822a934b9f7bec98ea629cc2f157c7ab94f256ff95b8aad42fde02c3571998' 
  AND token = 'tP2Krou1iakTMM6Fhg2dDMvXgXs84qdtDTnnKDS7ulc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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