SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dd56a356ecacdd7969e05c88a7e0da8923276eca246fe570b722bb558fd7c405' 
  AND token = 'BWqTb0UNUPT8YPFvjqioIO1udShsLIHvymD47ZnznAU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}