SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '44b8e35a601c58f8bc6e50c2aaae1e31ba29fc153c5b766dda40e1f835f79927' 
  AND token = 'spjKSfztokqGlIx0S76LJn0Fu31z79Rc75TupksItZ0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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