SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'df95fba1e97a0f18f858c631f39c6a561bff73eb4d61642c82e40094a97b4c4b' 
  AND token = 'CwJcAr3718KsGd+u+7uVUKiCslTnFYw9z/pq2+Cfy0k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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