SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1925a6043da29c19b694e29e0e94abd98f3bac7ecc99153d58bfacad2bc5c435' 
  AND token = 'OY0R57OjJJkfI6cwft21SfiPJiRDeNW+wfEZbTnvwYE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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