SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '22cf9d43c90752e157c090bb96e3c71ff352f71112f21f3823efa3a3537e04b0' 
  AND token = 'Zwzrf9uM+U16R/VBRdHLvpCHsVrtXJ3g64d8LJLRh5U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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