SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c18c1704c00ec7255b00ebff6a108d4098aa8a212e419729aef4a2e107972058' 
  AND token = 'DbdvcS8xCz4CMu/IOd5tpT6/qjSQFItS1qkXyCUeN10=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00060

JSON explain

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