SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1f8932123247b8f9236ff08fbbb87cadf9bfcf965ef01dbab158b8477ef5f82f' 
  AND token = '9rEeAZh5lrxTa/BYx/ivZvrF1BqP5cgMP3KCQw5YTvY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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