SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9e806117834181066021563f0d3720dd00febd827fb4def79a691608090d60b7' 
  AND token = 'Bwb4EZuRSoJcxdxxOlrf4ZVbk5UmndVCFVG5Nf+ZI7g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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