SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '97007e14a92b3e3424222d0380adfa61c7228386a12981c35ec125661a2f76c4' 
  AND token = 'zd4slvFfpKBFiGUSbh53ItiYwrODgVktZgW3QnCXGDA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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