SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd10de61be3bba55436078cdde20b5102923966a24295f54ef22f37d693870bb3' 
  AND token = 'W/RQZyPEHGZ0lrijSTENKQLbM7vkHHZhSYHso7Hn8tk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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