SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'f5e29afaa02180cd2d2c026d01604b3b6e02e54e728be52a741cfb2a55908f2e' 
  AND token = 'QQt8kd/gCcTN17Os8ET7GfDKTE9dySHGHYnXyQQilXU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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