SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3640c5c3892590b947bba5226dd74ad11c8f508a0242948016f3ddceb8b15456' 
  AND token = 'GuYyz2NSeaQksVTcjJtO0znsFFepwDyhVPXzgiqLrWc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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