SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0f0ee93aa853bab03d1d452326a0e95e2ee97328d8657ce271eec5334cc880b0' 
  AND token = 'HvU6NvSNMYXezea8iP2BbrGiKTzCV2UUjLHDmQIAtOo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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