SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '23bc92eecd22c18d7b35da0596730e83ddf0c341dfca5416d76e60fec1ce8ef9' 
  AND token = 'XlCWYDCoq8XdXUAcbz5u6eQygY3w2OTi2+hoKcH22GI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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