SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '70eca5463e0fc8d70f2872c26cb1f09311462ebb53746fc8402502089f08ce45' 
  AND token = 'AB0ZoCIs5aVMk6tYpkhBXCOhlynqBZTfz2ji2JKUqZA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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