SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cca6cce660078802f7d09ad7f20692e973383818350d0f1d773814d734285807' 
  AND token = 'XfMHRQBNszyNIhQHxHxvhnNe/Z5LGv7C4HZNUca7t68=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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