SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '91c1056333539c554b59528c098a90a48f727f6f86bb79fb8059a6f1afb06161' 
  AND token = 'QcFST5FHavzNGBN4d0IGSiQLrdzbRuP2t9X5rfHYcgg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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