SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7f2cbda06d742eaf67a96d003bcaeed0e106fe1cfcfcef84a7cc20cfadc4ae48' 
  AND token = 'tbJVObccEYKX6hGcA/GjFu9inaSjKvf7oY4OchNuMhQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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