SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0478f47f4ba8030cd82d292b1d0d66751fe593b9d806c1f08aeea2a02305face' 
  AND token = 'lL/V3XHfnyj2/sahQdGu5VKlXtkNdvCahivrzl7J1Ys=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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