SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '37127b0600ef22e20d0358262accc894f97dee87c3a8d90ed93df7081b331809' 
  AND token = 'Qvy9evwA9wYYiip/7M/vEG29NYhTMqJQKWJUWeK/n/M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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