SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0ec12710d82973db4fa15c5b4357eb94497d8fb978aaeb2f100eb0d8c6b6cb60' 
  AND token = 'Kr1ngFZ7Wh3lKG0XmxXoBLxRJ6ZRuiHDG02SU5fVmxs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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