SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '975a44554a8311ff2db8aa060b83392064ff25235d16046bd47b3692c7f32aef' 
  AND token = 'yviZydlMx+tTj2Vp+erfxRSpkdoSjNpJjowKFX+OzXs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}