SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4ba937eb4182a8e3523984420e1d2b93822c39b7c823a949e46853423c55310c' 
  AND token = 'b1Sna9a7gvWEAwlUGos+JnGuxrN4TwKrveOE+DkaYG4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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