SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'da593c61bef9c77a299f86fe847a1db1af063c07c870c311581d72e2783d868c' 
  AND token = 'WVXVDgB4sugzfQZCqOvSrVYEzdLGKUq3SuLd5tP7UJ4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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