SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '288da6ad7a63c90947076d5416116df305481cd1c0b9d64a5bd0e90c39e4f0ae' 
  AND token = '9YUVkxgtGzawjJ/ugp0r/bb/kgkE25+M/4ObFt6c6hU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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