SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6556c871f72428ac799c03f6a8e74a26c19453d5604d7d7c4d53a1f4eef845d7' 
  AND token = 'kUBAb1cYd0NAKFwH5GIjhhjr3GINtUT5UudRvp5sZgU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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