SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fdc0bd1a1a78c584c2511286b0151fc386dc3c38d1bd48b231d0c5a668292c55' 
  AND token = 'mNZFM7YAJYpIngPAjSkJYWs2V9RzlYMnY1Ifd1aCP34=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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