SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '18f2267e94b0e15d903da87f84807efbaeb63cf75b1eefae821ce1acb5889512' 
  AND token = 'z1qdAKeJWk82uxlN69O0duASLbrwp0a5RZom81uLwOM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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