SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4c91bec9c8ff51063898888d7d2ad666ccaf160eaf7460b4e9063d7e4e82d66e' 
  AND token = 'QH0ZGxZi5W2RquYFiN4VYzbFZBnniQqm8L/eVPO+cJA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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