SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '116ec1c8a5540f0bdfd12cd9e0b02f49f2d6ba6709eca72e025986de4bd8c8ac' 
  AND token = 'yagbCV00g7JuBYCcnTBnITXoXR0ckpztpPYeFSCCzFQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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