SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0157045067c105280731c7be876c0d2d6564fa45928d222949cd925a6e409c42' 
  AND token = 'foSRD5bUH7T2zix+g1U/G1ynI2wOCXJssIbYq3pzYVs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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