SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5b7cfcb9e2f709f9b06d13d72ac753b93a74a2f6482095ee2343c4ebbae07e77' 
  AND token = 'h2y03U2qHvBSwuBbidZFfknr1yLVnCBtpgfFEgjTqCg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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