SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '414c8a8c0d1950d97c513ced394104b0172124c8b54ca9159eef530217911ce7' 
  AND token = 'LSFYdKxntqAd7QAkVEX2DT+moomoJ4axJTknYVErwWI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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