SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ee4bede23511f9a94d61828b1fabe80ba5bcd7a723e279c3e41f1dda6dced5b3' 
  AND token = 'ZLLu6J9ro/26f514ksQvAqSwb34lcYJNMcB9HaG6n4A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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