SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2c441392ff02f9947dc277dd9e6df151c664dff9497f8c354200a5f4f8bacf7f' 
  AND token = 'XgOCw8zhAms8WSkYbvpiGvZhA93CTrl9JAAH8wpzUvM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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