SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7c0845f9d481f7a7d46b0b2de51079172088328d5238718c77e01f11ddc62a9d' 
  AND token = 'O6KB38UVLFGYD71veU/SPBchRVoMxzeZjB1QVAYimC8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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