SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '99c32b0f1074300ff2cc76a32d890ad649e3dbba491c10ea17b4cdeaf22bf173' 
  AND token = '39WJgHZeeVLKPg+8ZG1j9iBRjsEnK9KRDS+zsUkHpYs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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