SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '724d8c9d8c476cdd4a182716b4c2fa46159c2ead59cbf130b4fc0102e8f92667' 
  AND token = 'zwvjlF52RKYariuI7gcsqzMwZLtpOPBypD9ePshUCgU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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