SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0905e6f710aa08c96857974bd154f5fb9dd725be612a966ee0fab4c592e1dde6' 
  AND token = '8+jvZ9Dyp9+SZa2t6/hgwK7Avbq0V6oJp+PK4vsgzXw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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