SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b032110b4b662d8b9d58dea87ec5894748be9edd678c2a69d167fa707bba958c' 
  AND token = 'KVMiVGeI3Al+J+4RhorskdVvm9oroQvDPbMD4xHIHRQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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