SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8bcab764979d345e41c44e4e2fe0c35896f951c0a85a699c2c562e4a08af0ff3' 
  AND token = 'a5TtUmgLNYMS1LkJQ2OGHQvPE89CD/gjDMCJxeYIJYg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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