SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '17a290e0b0260dc869d192fdbdbbeef7fef1de48db3eca9cbc7357f0365bbbfb' 
  AND token = 'RZpDRjzn2Mw6SyoK40PfhHLrnDF22Hsp4zVN5j4lsXk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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