SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a1b91e5aada2b741cc5867f7044a9d9b4e664c06cce66b89a343497fa3322a2f' 
  AND token = 'Q2fTzs8StrtITyiJF0gySZq+bZaBAJJCqvplwASwn3Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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