SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ad55f4c30c6392930bf4681019380f22980b6b6ad82163dc22729f116412d58d' 
  AND token = 'qHVihktNfNja5+mn045Xox4pwIC8PpEuKF+bdpvAvfs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00064

JSON explain

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