SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3def87040a60093848902c1f673710436de1dac872053194c97d1ff5aa14c925' 
  AND token = 'Ih3wmCryN/Q/RE+iWvBMk/7S5VcJJ7xsgK+eOChSv0E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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