SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd8a80fbcdbbafee02b07f202f55867c41c265ffe5ed538dec99780f148e25e11' 
  AND token = '2uVL3FiHFPEBG61TmVDKViwPhuUnpRi9Nhvi5J3qYmU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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