SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '360db84a9657b71b2edc99f9611ae3773b061ca19aadffbf0ea2e4207de362c9' 
  AND token = 'kvqXVdKWAhdK3tRQ9Jde9RFXnxdyNyk0RSBR+Xffcrk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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