SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9fd40cdfa69a62bed2375336b508cebfc915ac925e0ddf463acfb21be24bfb15' 
  AND token = 'BYLMcHi0ujDpWdwS6+SU2R4rsXQPRdA/63lFYgVrcvs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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