SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '80b2a98aeb9469413cf7b5c3330696da4ffb4c6253aaa396249068486e8bbcf7' 
  AND token = 'xk7CjbjxXdnTnnWqOftj1magjgaIgZ3Af1gcAzB7hmw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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