SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '70599e8900a639072ade0b5f1a0f7bad178144ea9f450f665aa5d85d97383cc4' 
  AND token = 'wE/KWQGJLnWf3GpJfctZqoADSv+/Z7Qw+8PwmuE3+iI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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