SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'fbfeb23812b21b5f9453a08efdc58079069e71944af66755c6d72cd04df16b3a' 
  AND token = 'vNj0VYFYEweqlMSLKKEcY/YHMFuV8eLOsiPaICIJk1Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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