SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1be995c8d17f55c261bc4358ac85c6f34b54028af5851332f1143f0b76e9e973' 
  AND token = 'dH4LTp0CPv7AYzJ9dDEPuO56KB5DhFUWbPqVKvSBqkc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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