SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '178d5710ef6f2689a02f396eb1e12fcf73271c910d035bf1e1d62bf14bd54df3' 
  AND token = 'bkbhIadEgVJtSTav4VTxrPqpBndvMFAJe6wVpJCO2Pc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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