SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '236f09190108a980dfd65e8ccfda90c564c7f403e40a55ac348879e9b20cd230' 
  AND token = 'voFiFpHwVKBtV38XILdor90K8I5bDvba9YIGXQ2M7Ys=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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