SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'bbcef8a3456323d3103c61032f0c63859aa087c93a89583d51e3c3b4132cc0b8' 
  AND token = 'XXLrlI3e12rJwgyMFITGllnVnrkd1zRIpEx+bmracTU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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