SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '07c3b5eb843f215a4f15ece005e0b2a2877236647c7a66f4a7585fc70a3e6c1b' 
  AND token = 'bZjCDkqDi9sFJmzNnZQuAMlGXBgu/E/+ufvezYI8Yq8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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