SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'db65d5ef9253834bca9858349130ee491390462acbf36cf471bb8fcc0a941f67' 
  AND token = 'p9oB0dO2yjJZQMnYAKjjzBXgAj5YkhmNjvqm4MJq7dU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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