SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '84ae309f6cca24577fc9a7e491c28dd8bdc0376c1f7f627ee0ca8dff198da177' 
  AND token = 'uwi0yu7Xzee0hMsjbpELnSoqjHAEwHi1dgS6D9kRsHU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00055

JSON explain

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