SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4afa19f112f2ab0bff94cb5fd6215bbbc596e372afc223ab31833e0a84b983a3' 
  AND token = 'En4OHpWCpQJN3zHZvWF7h6J/YfwzpzKnDFD6XlX+OQc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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