SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e94aed5288b47eddea060b531497f55a77270c2480179be135cae49464caa9f5' 
  AND token = 'GJyOKLdkFKWB4GkB+1BD8HJNUPGbnaGs3eYDGd/2w4I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}