SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a69bf05ffa6e2dab3444859f04b217a49fe27efc53179f9c1628b98d9e290c44' 
  AND token = 'Jbf6wx6fWMUG16wxBuFjIFUuTCEM1v9+TSzB4bxWufA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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