SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7d69ef5dda865608f1843ea1b5c52b0b61741daa512504d8d5d79566dfc70892' 
  AND token = '5Neu4vGqrf6pas5VcrEGpvqaqc+FQmsuflAw/XEJmkQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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