SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '831c2438f3b9cf5b5096936bffde31a66fe2b571679872db557638e43a37695d' 
  AND token = '6BgJyLR3ooEZEwV+HI4+4KrE4UjYzf/edXiVKF3BwQE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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