SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5ef87a476b7b440c375503037959ebd33ba4114b6a67c556e77e94e73544f9df' 
  AND token = '7tVHNnWl7cpkjLWbfW+nndP7S5QDjwlhuG/YZ/AUONU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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