SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '829c00b59fddc6a1b9a88f9b3fee9007008475a24274c325dac1ea9c11c101ad' 
  AND token = 'kAloMTKHn7Cp/D96DU77k+WDWObotIXOxNDQGsS6H9o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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