SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '215d75086ca221643274e6a286ce69f4e532030881327f24ffac002715e1c13d' 
  AND token = 'HWlgBvfT+riJnLXu/FEyW/+SWAlC6GgctN403GTaihA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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