SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5828046e43a80431933c5f9d6bf64fae89251f11a9c83fec63ed7887d1d4d79c' 
  AND token = 'rEGcVd4qwEV2YXYW541KatqkI3xtZdGbjvEBPZX3JA4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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