SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '256ffbb0ba80dbc3d129bdcd335503d6a4201a9bc7704a1322cf6c2df0175909' 
  AND token = '34nAER6lpaOMYrT9xKpK6gN9vlUvt/okZaH958ji/Dg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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