SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7b3e34ac9d8ead7034c0d4c2a0a44b00ca856f62668bb09057bc236624b46881' 
  AND token = 'Nbkn+iGQ1NRg/vSnpyI7ajAfeQMZlKwtN+xsMEjaLmM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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