SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3724bb36dbf0982c7f4e2c5947ecb80ea0544a51e4336f87a1feb55fc83218a1' 
  AND token = 'SQwnZwoDd2aek0A9vDil52btPHHIDKkbbOY0lTIZBZ4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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