SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '17d2108f0d0655b5874a15f64524f457df070b8e99b3fed05a813d38fcfcaad5' 
  AND token = 'FaIzcNat9drpJ9wGdhusPBhJQyVkdSv20JaoNugcJvA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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