SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f5198205d9030436dad28fd87a001dbd35439017b76b47e81c25a03219158024' 
  AND token = 'BYKQKRtw6cqCs9YEA1D6q151HRADNvpOKufxsZ9vIvY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}