SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f614c2292c62455c968ecadc26737f788b34044a2e2d711d4cdc6aa9bc54f5a9' 
  AND token = '3PioH7o0WrzGEeCd2MUFDh955O9uDzwcBUaVAcxwe+o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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