SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f0534649fe54fa1f0b7c139893ab9ebc0846f52e2c79bd22e14cd43ecad2ae11' 
  AND token = 'UMBlEo82RdVnYMwE/MCNjpnpgCxUadbMKBl94cTTSrU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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