SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3d04fa21dd3255d5c0ce4f4446123a8b7a09f1be572bc0318f7ba3a924017693' 
  AND token = 'PXx7JzSOA9AYK7MxqOyG+JJDQJPW0pP4Dm0KOjrov3w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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