SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '98b0bd723139eb320bf65916d820b514e875c0fe0ef45225d1498a5f75ec1fc0' 
  AND token = 'cjeLvrFc0lAxDpjaVmvlwuSOu/BUkEbowga454BFRqo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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