SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0f953d12676fa8917a3c86bcd1ad44a2aca5de5833e9f971cdf01bec7152b573' 
  AND token = 'Vhp+yBvemiurJTJnr6iVpaw5+oEbYBhH/S2KnsOWGxo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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