SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5945e1c87b256bbc58998e34f5f6f2cb726ba00bf56f72c1d8cbdaf3dd9af18d' 
  AND token = 'CKZ8PsXnpqNR1tn5LH/iFlwU+krUmGauj+D6BL5OtxE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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