SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '719e9668b691345f39c645d62bc06ba0386eb7abf85e0c0ae2e0e141184a26dc' 
  AND token = '9TjG/caqz6Yg6py6G1YFZgmSG95qJm/w8UXSlvZ+RSk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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