SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c24e2cf48f896c6374a8f80ebc75ace272aaa83a476bb5745bb89793dcd7800d' 
  AND token = 'XnsU6iUDYQN3FIP2hbyEebZmI+MTRY8eoGNOR8Xys5o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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