SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bcd84313ba94d33b1fb116595798160daab14ecf73c66309cc30091a23dace22' 
  AND token = 'IDh/FrJUMTh2pqUv0rp75O0Im1XSq/8uTmalUdA/acw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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