SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '59134134a71b3497bfd9ef387fc7b6c80c2430b3220007f15a7a8b0fb1c16c08' 
  AND token = 'GeKTHLhLLK43f9szgmOsJJufH7/D/El8DPqVErlug5k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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