SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd159f50a111a7e535f9473d3c569c67f1deba1a075603523bf105ca825a2f515' 
  AND token = 'SKsnHsbFOE77wvJ9VtIc6zAEIaFffXlLnvNu/0I3aqQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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