SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e4c1e711ae01c0dbf38ceae60d47a525507dca6489c44cbaa12da7d2c62894f1' 
  AND token = 'u5rChQWgNloAwSBSfSBfnrtnVe2u20Hp3RTavxDarf4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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