SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '143f957494b0dce96b281ca5341afe5cafa72cfa384a1bb5f767412313380ef7' 
  AND token = 'o3mIRx2/3oLQaUTMR9YaYVU5c8C1aaSFbU/UZ1oUhCk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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