SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '36f546814f2f5174cd9e4b8db8b31f5fbcf92fbda3300ec6e92cdd0249cb012b' 
  AND token = 'NqD/fC3cRTRN5nN/QY7xEyOaUU21ukzCEaQg212qkTc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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