SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1ca4d948e2af7761fc769d2cb64f028a6543eabcb057edc91912260b09a88166' 
  AND token = 'ecdTwBLwpZ9KSVoYdpGCE4TafvWaLmQIOahDdoBEl6Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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