SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '214dcdaff154f4734f40f99a4bbcb4dcf4d5d039f542456cf49cc994994b7c92' 
  AND token = 'FbALVYDzjekJrK1+eL9tuEjuWD1hW6ROGaNd7WJ4hrU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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