SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '26dcc0c875e145a89f7bb471db5fe06643a4cb70f81eba093b652d7604474cd5' 
  AND token = 'rLBQw0mculUfXylkT55vKIP2FKzvMC3NK4iNcOKOIlM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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