SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f76c8473aeea4338ff3aa15df21ae838fc4d36c011bb9645e18876800f4a2a2e' 
  AND token = '+3uglychLaWWofyyouHvHExhSJ5vvhsngMhIlVTZeDo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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