SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '441d115957ca1accaedf92fe005961d1fce74feb6e519f5e8460bf99fea0b7a2' 
  AND token = 'yzgPSR0HVODqdwu+X5iVcWP5q/pQoHNAgZo+vG+eRCo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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