SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '68cb9ce714eedc1197b93b2c6826dc568c3da19133d66a15f16fe09ec59b2481' 
  AND token = 'HdK1kBMyzaJJ0CdmVvGHF7yeF0TMjVL0Nvedr9wvFIA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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