SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0c2c5a510fc16113c3ac9aa9ca0411e56f85b581918bd5b098a1faa47e4b8fde' 
  AND token = 'IJxJWHm8UlmE1h0lwsv7XRJQL8qBKREuVcVDdArls4Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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