SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b69608e6ad8cf1f04b132938ca612ff2bf4cb31ae3cc95b8a833416c073c6b2c' 
  AND token = 'd7bCj0erZHV6coiWSN3pyC7NeJMrXCdPxUQGpyq1Q30=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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