SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '132b42366a7ca5c87d30b71b98155f8a957d697bfd4d29d3fa215d4d81c069c0' 
  AND token = 't0BYamSwIzHxV4zV6N68qSy6nbHuxfKHCGn5ngD+6yw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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