SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6d928023527ba9cc734b5f34423d97cb92f7cc57bcc28989152dbbf7709241c4' 
  AND token = 's//ie1BNNv/qOD1R7jcDqzOyXrenH/1GzR0FOzhzyV8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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