SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '33441a19a2502d621b238cd3ee34869b90b28eaa30a93ec0495bc230be33c824' 
  AND token = 'xH51q0wqLD75jeI3pi21ZjGWESzdCGbczO17ZGcDgIw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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