SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '270aa5923ef105ed536f128158939bc4d9949493fafd123fd8435a378d12e969' 
  AND token = '8aeP7Z/gvTuAFHn3NtSVVQOPswHsoHiJs5n0cDHyy1k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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