SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9b19530b52a9928f26366ec82c52acbfb59d9a7c43aa029c3b1be9f75951e07f' 
  AND token = 'qty/+Up6qhbc9oZJeW5OzSwGxlpmyhQgwnQnddREAGI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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