SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '82b24fac3ae64d6f458c08943a87e6c07910ef5b441cbe7326fa357a06b4daab' 
  AND token = 'BW4wgeg8wNL/UN583GOftqw8oq/5+CpH0x/uD5kX4a8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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