SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '52d043e86c8b4a0561bb840fc1c79226a6a8d16ce8777ac9ae22a368e85ee017' 
  AND token = 'EiBVqb7nSYs8f67Rz3AZ8jcU8mKZdSVEQHp1XV09TA8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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