SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7b3df441b8f8831ff92d7594ee8e91d0b9788705859100a5ca19e1a7ecc37e95' 
  AND token = 'PhKCezSRId0hVY5dvJKtA8LlxnQBuYQNTeLdPSuoa7I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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