SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '59daf2cb8aa5bbd8595aa278a3001a01797be107a12363b5fb4947906afa3461' 
  AND token = 'wGfu86jUaRTe4LUFoXmbT5nYd0YFJacptupHpzfNiKY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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