SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '446f9699cc06add415ee70778d5a7be3644ddcc0bc639dd18ba0a1fcd79ad823' 
  AND token = 'bnVifQOley+0AzIl/tiUC0PaMsitlnbrNHJ1kOcPjcE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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