SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ace0a269336af42c7262022f08c3fe0e27f9503fdbf3fd23842a272b79660065' 
  AND token = '2wayp7dtgwi6uC3zLHEenAwybbhx32YU1ND+F4Pg6hk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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