SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cf545ce7fdbd796da553d0fbab42bd1e90567fc43372cdf3b0494ab72ef3b522' 
  AND token = 'dEeY/mBFz9GXPtwUzVwhXBZmI0vDLKfGL7jCUwLkMhM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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