SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a60a4f51300023c85c06148bc751171834146082a1ee7ed5b8db941b97a91380' 
  AND token = 'gVy2r9xFsgf3FywtktHjPMX3mqd+hszi/2pkoO+fzKY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00079

JSON explain

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