SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '29ee4c515b579eae47ae4fc7c2a03168ddfa766dd1dc0f712addfd13d5165ba5' 
  AND token = 'x3WGzK7D+09GptPulHOAH7XoMWuQrZCLIXC6z8+IQKw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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