SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '967233948806badd30e5fac51724fe4ac7e613b51ed081e52842d9558bd5b968' 
  AND token = 'ZVAYVGXTcFgYH1TAMqn05qiavxb98JQy5jSNhmCm76g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00068

JSON explain

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