SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cf911424d52fdde33c6f5bf157c33c20222060ca7dd1b3309b979969fcc660b2' 
  AND token = 'lNU9wrfqrkfmZef/SysMWWcPLVznno3ZMpq0PZd9WA0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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