SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0377a7d4167cba7411473fc6f4d135676194f75aa39d3ea17a79b9545b776e06' 
  AND token = 'EJIutatK2OIa0fuWyYe9upENeNuivuj+1KU6ERejHdk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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