SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9b73d5cd839e1c6caa9ffc2759af99cb434d2954951044b69d77632c7251990f' 
  AND token = 'uzIOL1W4tQ47UuCzt9l2hYnxSWqjjgFxdbaIqfFld50=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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