SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4afd09746605908e888dedf158bd0d602a89612dfc9dde573618a6a8585fa3e5' 
  AND token = 'Wk4XCgskI7c3U4QHlp7F5ONe8S47IpUJCye7eOANSqQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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