SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '64c4732f4ff7f784d6f69a90172a2ffef7e3860a96aec331553bfc04581c383e' 
  AND token = 'FEAWcf0CD5dK6HvEjJXfjrnWr+AnVkjMFwM2yOvrrHU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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