SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0afaba5f9b4344c948cfd17ee0ff8b48c97c574d7e8b02f1df9127d726454cde' 
  AND token = 'a7+BkGJ35PUlq1iHBuQlV96xfjogrzc7bvCmmUgBoco=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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