SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cc39ac6b9b0f1d1b210d8e6170c437082bdabaab9a86b240caa106f4dffec3fa' 
  AND token = 'HY23Sv4doPPnxoJYTfJqYpKCZHMHRndEveGa9X0J0Ck=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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