SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '87072f2f7c5c8d80aa185b2420f3835e5969914bb673e398ee055f1be183b14f' 
  AND token = 'NFLBlncrqu5bZnN4KdlY94aVJwr7fERzaatcjuSi+HM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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