SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'abb090579aaac16eaa1fe9e7e06be82b075e378b1871ea0ff7d703d1ada59665' 
  AND token = 'FbszAPq51F+tGuDEmwjzJU6EeEDofbC/54PsQfInyw8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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