SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '297cb0bce759cb5ad76f1797515a950fd981c7ba6760e17099975b89923884f1' 
  AND token = '+dRdgUa+cDaDi5IV0swcX5WKQGcPTfR0l2Yz+Swnn14=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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