SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8ec0fef6288e8bc9ba16c7c53ddb3fc23f3589ab0a768e368bb520e565226ede' 
  AND token = 'GIQa2mOkwe+XCGvjKsZbRecc8u9psHtopDberK4PbOs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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