SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5066b7dc1578d6469a14b3ca9ccfd242015945a46db14552e8f78f4b30b6f720' 
  AND token = 'wHDoyjL9oQhHWK/ug6sPNhKmxiOTCyjDYVK407Zp2qw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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