SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4b5d7f102bc1e8b3e8f508b79a5269d02096f9861641f5c8ff6bf4ef12884638' 
  AND token = '30v1u6s8CZ0QNJlRX8rKg8IH6okMTfGhOEG92k0KXmU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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